Corrosion gas pipeline protection devices. Typical Instructions for Labor Protection when repairing and operating devices of electrochemical protection of gas pipelines Repair and maintenance of ECH systems
6.8.1. Maintenance and repair of electrochemical protection of underground gas pipelines from corrosion, control over the effectiveness of ECH and the development of measures to prevent corrosion damage to gas pipelines are carried out by personnel of specialized structural units of operational organizations or specialized organizations.
6.8.2. The frequency of performance of maintenance, repair and verification of ECH effectiveness is set to PB 12-529. It is allowed to combine the measurements of potentials when checking the effectiveness of ECH with planned measurements of electrical potentials on gas pipelines in the ECH fund area.
6.8.3. Maintenance and repair of insulating flanges and ECH installations are manufactured by charts approved in the prescribed manner by the technical guidance of organizations - owners of electrical installations. When operating the ECH funds, their failures in the work and time of downtime are recorded.
6.8.4. Maintenance of cathode installations ECH includes:
Check the status of the contour of the protective ground (re-ground zero wire) and feeding lines. The external inspection is checked by the reliability of the visible contact of the grounding conductor with the electrical power supply housing, the absence of a breakage of the supply wires on the airline support and the reliability of the contact of the zero wire with the electrical installation housing;
Inspection of the state of all elements of cathodic protection equipment in order to establish the health of the fuses, the reliability of contacts, the lack of traces of overheating and subagrels;
Cleaning equipment and contact devices from dust, dirt, snow, checking the availability and compliance of the binding signs, the state of the carpet and wells of contact devices;
Voltage measurement, current values \u200b\u200bat the output of the converter, potential on the protected gas pipeline at the connection point when the electrochemical protection is turned off. In case of inconsistency of the electrical installation parameters, the commissioning data should be adjusted to its operation mode;
Making appropriate entries in the operational journal.
6.8.5. Maintenance of tread installations includes:
Measurement of the potential of the tread relative to the Earth with the disconnected protector;
Measuring the potential of the "gas pipeline" with the on-and-off protector;
The value of the current in the chain "Protector is a protected structure."
6.8.6. Maintenance of insulating flange compounds includes work on cleaning flanges from dust and dirt, measuring the potential difference "gas pipeline" before and after the flange, the voltage drop on the flange. In the zone of the influence of the wandering currents, the measurement of the potential difference "gas pipeline" before and after the flange should be made synchronously.
6.8.7. The state of adjustable and unregulated jumpers check the difference in the potential difference "Food-Earth" in the jumper connectivity (or in the nearest measurement points on underground structures), as well as measuring the value and direction of the current (on adjustable and detachable jumpers).
6.8.8. When checking the efficiency of electrochemical protection installations, except for the work performed during the technical inspection, the potentials are measured on the protected gas pipeline at the reference points (at the boundaries of the protection zone) and at points located on the highway of the gas pipeline, every 200 m in settlements and every 500 m in rectilinear areas of inter-settlement gas pipelines.
6.8.9. The current repair of ECH includes:
All types of technical inspection work with testing performance;
Measurement of insulation resistance of current-carrying parts;
Repair rectifier and other schema elements;
Elimination of cliffs of drainage lines.
6.8.10. The overhaul of the ECH installations includes works related to the replacement of the anode earthing, drainage and feed lines.
After major repairs, the main equipment of electrochemical protection is checked in operation under load over the time specified by the manufacturer, but not less than 24 hours.
Russian State University of Oil and Gas. I.M.Gubkin
Educational and Research Center for Education of Fuel and Energy Complex (WCC)
Munz "Antikor"
Final work
under the program of short-term advanced training:
"Protection against corrosion of gasneftepromysot equipment, pipelines and gas and oil and oil reservoirs"
Subject: Systems of electrochemical protection, their operation
Moscow, 2012
Introduction
electrochemical Corrosion Protection Grounding
The electrochemical protection of underground structures is the method of protection against electrochemical corrosion, the essence of which consists in slowing the corrosion of the structure under the action of cathode polarization by offset of the potential into the negative area under the action of a DC passing through the border of the "Construction - Environment" section. Electrochemical protection of underground structures can be carried out using cathode protection installations (hereinafter referred to as Ukz), drainage installations or tread installations.
When protecting with a formulation, a metal structure (gas pipeline, cable shell, a reservoir, a borehole casing, etc.) connects to the negative pole of the DC source. At the same time, an anode ground is connected to the positive pole of the source, which ensures the current in the soil.
Under the protector protection, the protected construction is electrically connected with the metal in the same environment, but having a more negative potential than the potential of the structure.
With drainage protection, the protected structure located in the area of \u200b\u200bthe validity of constant currents is connected to the source of the wandering currents; This prevents the flow of these currents from the construction of the ground. The wandering currents are called leakage currents from railway tracks electrified on the constant current of railways, tram tracks and other sources.
1. Cathodic protection installations
To protect underground pipelines from corrosion, the installations of cathode protection (GPZ) are constructed. The formulation includes sources of power supply of an AC network 0.4; 6 or 10 kV, cathode stations (converters), anodic grounding, control and measuring points (instrumentation), connecting wires and cables. If necessary, regulating resistors, shunts, polarized elements, control and diagnostic items (CDP), with corrosion monitoring sensors, remote control blocks and control of protection parameters are included.
The protected design is attached to the negative pole of the current source, the second electrode is connected to its positive pole - the anode earthing. The place of contact with the design is called a drainage point. The principal scheme of the method can be represented as follows:
1 - DC source
Protected facility
Drainage point
Anodic grounding
2. Cathodic protection plants
The operation of the WL lies in the conduct of technical and operational maintenance, regenerative and overhaul.
Maintenance of VL consists of a complex of measures aimed at protecting elements BL from premature wear.
Overhaul VL is to carry out a complex of measures to maintain and restore the initial operational indicators and parameters of the VL. In case of major repairs, defective parts and elements are replaced either on equivalent, or to more durable, improving the operational characteristics of the VL.
The inspections throughout the entire route of the WL are produced in order to visual validation of the state of the VL. In case of inspection, the state of the supports, wires, traverse, arresters, discontinuisors, prefixes, bandages, clamps, numbering, posters, the state of the tracks are determined.
Extraordinary inspections are associated, as a rule, with a violation of a normal mode of operation or automatic shutdown of VL from relay protection, and after successful re-activation, it is carried out if necessary. The inspections are targeted, produce it with the use of special technical means of movement and search for damage locations. Also identify faults threatening damage to VL or safety of people.
Complex of maintenance work VL 96 V - 10 square meters. Name of work Periodicity Conditioning of individual trees threatening falling on Vl and shrubs Security zone Vl, trimming branches of trees As needed Restoration of signs and posters on separate supports As needed Supporting support As needed Hanging wires As needed Hauling wire bandage As needed Removing sketches on wires As needed Replacement of torn grounding descents As needed Updating dispatching names As needed Grounding Ground Base As needed Seeling cracks, chosel, chips, w / b support and consoles As needed Repair and replacement of delay As needed Replacing Introduces As needed Replacing insulators As needed 3. Transformer substations above 1 kV KTP refers to electrical installations voltage above 1000 V. Transformer substations Complete 25-40 kVA used in PCZ are designed for receiving, converting and distributing the electrical energy of three-phase AC with a frequency of 50 Hz. A single-transformed KTP consists of an introductory device on the high voltage side (UHH), a power transformer, a switchgear on the low voltage side (RUNN). When operating the CTP, reliable operation should be ensured. Load, voltage level, temperature, transformer oil characteristics and insulation parameters must be within the established norms; Cooling devices, voltage control, protection, oil equipment and other elements should be kept in good condition. The sole inspection of the KTP, can perform an employee who has a group of not lower than III, from among the operative personnel serving this electrical installation during working hours or on duty, or an employee from among administrative and technical personnel, having a group V and the right of sole inspection on the basis of a written order Head of the Organization. 4. Cathodic protection stations Cathodic protection stations are divided at stations with converters of thyristor and inventory type. Thyristor stations include PASK, OPS type stations, Ukr. Inventory stations include operating stations, Parsek, NGK-IPKZ Euro. Cathodic protection stations of thyristor type. high reliability; simplicity of design, allowing to organize the repair of the station in the field by the forces of specialists of the ECH service. The disadvantages of thyristor stations include: low efficiency even on rated power, The output current has unacceptably large ripples; High weight of stations; Lack of power proofreaders; a large amount of copper in the power transformer. 5. Cathodic protection stations inverter type The advantages of this type of stations include: high efficiency; low level of pulsation output current; low weight (typical weight of the station with a capacity of 1 kW ~ 8 ... 12 kg); compactness; small amount of copper in the station; high power factor (if there is a corrector, which is a mandatory requirement of the GOST); the ease of operational replacement of the station (power converter) is even one person, especially during the modulus station. The disadvantages include: the lack of the ability to repair in the workshops of ECH services; lower, compared with thyristor, the reliability of the station, determined by a significantly greater complexity, a large number of components and sensitivity of a number of them to voltage jumps during a thunderstorm and with an autonomous power supply system. Recently, a number of manufacturers supply SCZs with installed blocks of lightning protection and voltage stabilizers, which significantly increases their reliability. Maintenance of the converter is made taking into account the requirements of the technical description and according to the CPR schedule. Regulations are a system of planned-warning repairs, inspections and verification of the proper operation of ECH funds. These works include identifying and eliminating malfunctions and defects, testing control-measuring instruments, accumulation and analysis of materials obtained characterizing wear, as well as performing periodic repairs. The essence of a system of planned-warning repairs is that after testing by means of ECH, the specified number of hours is carried out a specific type of scheduled repair: current, or capital. 6. Current inspection (MOT) A complex of work on the care and control of the technical condition of all the structural elements of ECH means available to external observation, carried out in preventive purposes. At the current inspection, the following works are performed: checking the testimony of built-in electrical measuring instruments by control devices; installing the arrow of devices to zero scale; removing the testimony of voltmeters, ammeters, the electricity consumption counter and the time of the transducers; measurement and, if necessary, adjust the potential of the structure at the Drainage point of the SCZ; Recording about the work performed in the field journal installation. The current inspection is performed by the bypass method throughout the entire period of operation of ECH structures between planned repairs. 7. Current repairs (TR) Current repairs - is carried out with minimal repair work. The purpose of the current repairs is to ensure the normal operation of ECH objects to the next scheduled repair by eliminating defects and by regulation. During the current repair, Ukz produces all the works provided for by technical: Cleaning detachable contacts and installation of compounds; removal of dust, sand, dirt and moisture with elements of the design of mounting boards, coolers of power diodes, thyristors, transistors; tongue of screw contact connections; measurement or calculation of the resistance of the DC circuit of the DC; recording about the work performed in the field journal installation. 8. Overhaul (cr) The highest view of the planned-warning repair, which produces a replacement or recovery of individual nodes and parts, disassembly and assembly, adjustment, testing and adjustment of ECH system equipment. Tests should show that the technical parameters of the equipment comply with the requirements provided for by the regulatory and technical documentation (NTD). The volume of cathode protection stations includes: all the work of the middle repair; replacement of failed supports, pods, consoles; hauling, and if necessary, replacing wires, insulators, traverse, hooks; replacement of defective blocks, switching equipment; partial or complete replacement (if necessary) anodic and protective grounding; inspection of the contact of the cathode cable with a protected structure. 9. An unscheduled repair An unscheduled repair is a repair that is not provided for by the PPR system caused by a sudden refusal associated with violation of the maintenance rules. The clear organization of the ECH service should ensure that such repairs are carried out in the shortest possible time. In the process of operation, Ukz should take measures to minimize the possibility of the emergence of unscheduled repairs. Works performed during all planned-warning and unscheduled repairs are recorded in the appropriate passports and journals of exploitation and repair of electrical protection funds. 10. Measuring points To monitor the state of comprehensive protection on underground facilities, instrumentation should be equipped with measuring points (kip), which indicates the binding point of the connection of the control wire to the construction. Operation of instrumentation (kip) provides for maintenance and repair (current and capital), aimed at ensuring their reliable work. For maintenance, periodic inspections of the instrumentation should be carried out, preventive checks and measurements, eliminate small damage, malfunction, etc. Measuring points (instrumentation) are installed on an underground structure after laying it into the trench before the ground begging. The installation of control and measuring points on the existing structures is performed in special shurs. Measuring points are set to the structure not more than 3 m from the connection point to the construction of the control wire. In the case of the disposal on the site where the operation of testing items is difficult, the latter can be installed in the nearest places convenient for operation, but not more than 50 m from the point of connecting the control wire to the construction. Instrumentation points on underground metal structures should ensure reliable electrical contact of the conductor with a protected structure; reliable insulation of the conductor from the soil; Mechanical strength with external influences; lack of electrical contact between the electrode of comparison and the structure or control conductor; Availability for service personnel and the possibility of measuring potentials regardless of seasonal conditions. The current inspection of the boiled is carried out by the bypass method throughout the entire period of operation of the ECH structures between the planned current repairs and during seasonal measurements of the protective potentials of the workers team consisting of at least two people. Before performing work at control and measuring points it is necessary: Conduct measurement of gaspace. Determine the working area and designate it with appropriate safety signs. At the current inspection of the pile, the following types of work are performed: External inspection of Kipa; Checking the health of the control output and conclusions from electrodes and sensors installed in the pile; Alignment of the kip perpendicular to the pipeline. Measurement production Conduct measurement of gaspace; make an external inspection of kip; Determine the picket and the number of the protected structure on the identification plate; Open the locking device of the kip and remove the lid; get a device for measuring protective potential; make measurements on a kepal block shoe; wear the kip lid and close the locking device; remove the installed security marks; Continue moving along the protected structure to the next control and measuring point (instrumentation). 12. Current Repair (Tr) Under the TP of control and measuring points, all preparatory work is carried out, the operation of the current inspection and the following types of work: Checking the health of the control output and conclusions from electrodes and sensors installed in the pile; cleaning the locking devices of the columns heads; lubrication of rubbing surfaces with lubricant cyatim 202. painting of control and measuring speakers, racks of columns; oderovka or restoration of crushed stone scenes; update and / or restoration of identification tablets; checking insulation of control wires (selectively); checking contacts of control conclusions with a pipe (selectively). 13. Overhaul (cr) When performing the overhaul of the instrument, it is replaced by damaged columns, racks or columns, replacing the control cable. When repairing control and measuring points, work must be performed in the following sequence: conduct measurement of gaspace; designate the working area with relevant safety signs; open the pit for the installation of the point; open the lid of the item; if necessary, make welding of cable control conclusions to the pipe; inseulate the welding place, restore the heat insulating pipeline coating; stretch the cables or wires to the pole rack cavity, providing their reserve 0.4 m; install the rack in the pit vertically; fall asleep with soil with a seal of the latter; connect cables or wires to terminals of the terminal panel; perform marking of cables (wires) and terminals corresponding to the compound scheme; close the lid of the item; apply to the top of the rack of oil paint serial number of the point on the pipeline route; fasten the ground around the point within a radius of 1 m with a sand mix with a rubble fraction up to 30 mm; remove set security signs. Prior to the installation of an control and measuring point, an anti-corrosion composition should be applied to its underground part, and the above-ground part is painted in accordance with the corporate colors Gazprom. Anodic grounding By location relative to the surface of the grounding ground there are two species - surface and deep. Like all technological installations, the deep anodic grounds (gas) require proper technical operation and timely maintenance. Inspection of the state of gas, maintenance (lifting of the drainage cable and painting gas) measuring the resistance and currents of the anode in order to determine the deviation of the resistance to the spreading is carried out 1 time per year after converging of melt waters and soil. The results are recorded in the Journal of SCZ and the SCZ passport. In the event of an increase in gas resistance (this may be noticed according to the indications of the Ampmeter of SCs or a reduction in the potential at the drainage point), the protection zone is reduced. Maintenance, Periodic Measurements Gas, Measurement Registration in the field journal Ukr and analysis allow us to provide a reliable gas pipeline area and predict further gas repairs and rehabilitation activities. When operating the cathode protection system of underground pipelines with deep anode entries (gas), the problem of replacing them occurs after the end of use. This process is composed, and costs are comparable to installing a new earthing. The desire to maximally use the well led to the fact that noble, low-soluble metals are used for the ground material, as a result of which their service life increases. However, the cost of building such gas is significantly higher than earthing from ferrous metals. In recent years, the gas of the designable design is intensively underway. Thus, improving the efficiency of cathode protection of any underground pipeline can be achieved by using insulating flanges or insulating inserts. At the same time, the greatest technical and economic effect gives the use of insulating flanges. Currently, Introduced Introduced Flexible Anodes (PGA) for Cathodic Protection (KZ) of oilfield facilities to ensure the ability to reduce the costs of anti-corrosion protection of pipelines and NGOs. The constructive feature of the anode nodes, to protect the RVS, does not allow them to be horizontally on the bottom due to the possible blockage of the bottom sediments of the perforation holes of the dielectric shell. Operation in the vertical arrangement of the anodes is allowed at the level of the aqueous phase not lower than 3 m and the presence of an emergency shutdown system of the SCZ, with a smaller level applied protector protection. Technological efficiency of PGA To confirm the technical characteristics of the ELER-5B, the manufacturer of the technical characteristics of the ELER-5B, when protected from the internal corrosion (VC) of the capacitive equipment, NGDU "NN", together with the TatniNipneft Institute, developed and approved the programs and methods of poster and commercial tests of PGA. The stand tests of the samples of ELER-5B electrodes were carried out on the basis of the CACSO NGU "NN". Fishing tests were also carried out at the NGDA objects "NN": at the DNS-2 TsDNG-5 (RVS-2000) and the OKVSN TsKPPN (horizontal substitutenico-200). During the stand tests (Fig. 1), the velocities of the anode dissolution of the ELER-5B electrode in waste water were determined at the values \u200b\u200bof the maximum allowable linear density of the current current of the electricity and the effect of oil on the technical characteristics of the electrodes. It was revealed that after blocking the surface of PGA oil products, the electrodes are capable of fully restore their performance (self-cleaning) after 6-15 days. The visual inspection of the outer surface of the samples participating in the study did not reveal the changes. Bench trials confirmed the technical characteristics of PGA Mark Eler-5B declared by the manufacturer. When preparing for commercial testing, calculations of the ECH parameters of the inner surface of the RVS and CO were made. Taking into account the specifics of the design of the PHA, mounting circuits (Fig. 2 and 3) of their placement inside the capacitive equipment were developed. The estimated length of the electrode for the GO-200 was 40 m, the distance between the anode-bottom surfaces is 0.7 m. The total protection current - 6 A, the output voltage of the cathode protection station - 6 V, the power of the cathode protection station, 1,2 kW . The estimated length of the electrode for the RVS-2000 was 115 m, the distance between the "Anode-bottom" surfaces is 0.25 m, the "anode-lateral surface" - 0.8 m. The total protection current is 20.5 A, the output voltage of the cathode station protection - 20 V, power of cathode protection station - 0.6 kW. The estimated service life for both options is 15 years. In the process of testing, the objects were monitored at the output of the SCM and the current forces was adjusted. The potential offset, measured by the steel measuring electrode, was in the range from 0.1 to 0.3 V. According to the act of testing by the specialists of the TatniNipneft Institute and NGDU "NN", the PGA was inspected, mounted in GO (200 m 3) on the OKVSN (Fig. 4). The anode's operation was 280 days. The results of the PGA inspection showed its satisfactory condition. 16. Economic efficiency of PGA The design features and characteristics of the flexible anodes of ELER-5B, according to NGD, made it possible to reduce the costs of arrangement in comparison with the protector protection by 41%. In addition, with the introduction of the anodov ELER-5B, a decrease in energy consumption for RVS protection is noted up to 16 times. The power consumption for the protection of RVS NGDU "NN" was 0.03 kW (according to OAO TATNEFT from 0.06 to 0.5 kW). According to the method of calculating the economic effect, represented by NGDU "NN", when introducing this type of anodes in comparison with the protector protection, the economic effect will be 2.5 million rubles. (on the average annual volume of leadership in repair and cleaning under Tatneft OJSC). The expected economic effect of the introduction of PHA to the RVS, annually launched for repairs in OAO TATNEFT, is 3.7 million rubles. The total annual effect will be at least 6 million rubles. Main conclusions: Conducted bench and commercial tests of PGA at NGDU "NN" showed their high efficiency in the protection of capacitive equipment from internal corrosion (VC). The use of PHA in Tatneft OJSC to protect the capacitive equipment from the VC due to cost reduction in arrangement and operation will allow to obtain an economic effect of at least 6 million rubles. 17. Protectory Protection Protection of underground structures from soil corrosion by protectors under certain conditions is effective and easy to operate. One of the positive features of the protector protection is its autonomy. It can be carried out in areas where there are no sources of electricity. Protectory protection systems can be used as the main ECH: When interim protection; As a backup protection; to equalize the potential along the pipeline; to protect transitions; On pipelines of a small length. Protectors may have different shapes and sizes and manufactured in the form of individual castings or molds, rods, bracelet type (semi-colts), extended rods, wires and tapes. The effectiveness of protector protection depends on: Physicochemical properties of the tread; external factors that determine the mode of its use. The main characteristics of the protectors are: electrode potential; tokotdach; the efficiency of the protector alloy, on which the service life depend on and the optimal conditions for their application. The design of the protector should provide a reliable electric contact of the protectors with a structure that should not be violated during their installation and operation. To carry out electrical contact between the protected construction and the protector, the latter must have reinforcement in the form of a strip or rod. The valve is inserted into the protector material during the manufacture of the tread. In Russia, under the protection of underground metal structures from corrosion, it was found in the largest application of PMU type, which are PM maghic anodes, packed in paper bags along with the activator. In the center (along the longitudinal axis) of the PM tread, there is a contact rod from a galvanized rod. A wire of 3 m long is welded to the contact core. The location of the conductor connectivity with the rod is thoroughly isolated. The stationary potential of PMU magnesium testers is -1.6 V to relatively s. Theoretical current accounting is 2200 a * h / kg. In order to reduce resistance to spreading and ensuring sustainable operation, the protector is placed in a powdered activator, which is usually a mixture of bentonite (50%), gypsum (25%) and sodium sulfate (25%). The electrical resistivity of the activator must be no more than 1 ohm * m. Gypsum prevents the formation of a layer tread on the surface with poor conductivity, which contributes to uniform wear of the tread. Bentonite (clay) is administered to maintain in the activator of moisture, in addition, the clay slows the dissolution of the salts with groundwater, thereby maintaining a constant conductivity, and increases the service life of the activator. Sodium sulphate gives easily soluble compounds with tread corrosion products than ensuring the constancy of its potential and a sharp decrease in the resistivity of the activator. As an activator for the protectors, in no case cannot be used coke trifle. After installing the tread in the ground, its current processing is installed within a few days. The current protector depends substantially on the resistivity of the soil. The lower the specific electrical resistance, the higher the current protector. Therefore, the protectors should be placed in places with minimal resistivity and below the level of primerization of the soil. 18. Drainage defense A significant danger to the main pipelines represent the wandering currents of electrified railways, which in the absence of pipeline protection cause intensive corrosion destruction in the anode zones. Drainage protection - removal (drainage) of wandering currents from the pipeline in order to reduce the speed of its electrochemical corrosion; Provides maintenance of stable protective potential on the pipeline (creation of stable cathode<#"700621.files/image019.gif">
Drainage concept: Traction rail network; High-grade device; Overload protection element; Element of regulation of the current of the electrician; Polarized element - valve blocks collected from several, connected parallel to avalanche silicon diodes; Protected underground facility. Drainage protection in our enterprises is not applied due to the lack of wandering currents and electrified railways. Bibliography 1. Beckman B, Schwenk V Catodinal corrosion protection: Handbook. M.: Metallurgy, 1984. - 495 p. Volkov B.L., Teres N.I., Shuvanov V.V. Handbook on the protection of underground metal structures from corrosion. L.: Nedra, 1975. - 75С. 3. Dienko E.I., Novoselov V.F. and others. Anticorrosive protection of pipelines and tanks. M.: Nedra, 1978. - 199 p. Unified corrosion and aging protection system. Underground facilities. General requirements for corrosion protection. GOST 9.602-89. M.: Publishing standards. 1991. Zhuk N.P. The course of the theory of corrosion and protection of metals. M.: Metallurgy, 1976.-472 S. Krasnoyarsky V.V. Electrochemical method of protection of metals from corrosion. M.: Mashgiz, 1961. Krasnoyarsky V.V., Cikerman L.Ya. Corrosion and protection of underground metal structures. M.: Higher School, 1968. - 296 p. Tkachenko V.N. Electrochemical protection of pipeline networks. Volgograd: Volggas, 1997. - 312 p.
9.11. The results of the measurement results of the first stage, taking into account the measurements on adjacent communications, are analyzed and decisions are made to adjust the operational protection modes.
9.12. If you need to change the operation modes of the ECH measurement, they are repeated in all points located in the range of protective installations with changed modes of operation.
9.13. Adjusting the operation modes of ECH can be produced repeatedly until the desired results achieve.
9.14. Ultimately, the defensive installations must be installed minimally possible protective currents, under the protected structures in all measurement items, protective potentials are achieved at an absolute value not lower than the minimum permissible and no more maximum permissible.
9.15. Finally established modes of operation of protective installations must be coordinated with all organizations that have underground facilities in the areas of action of established installations, which they give confirmation in their conclusions (certificates).
9.16. In cases where during the device, it is not possible to achieve the required protective potentials on the protected structures of the required protective potentials in all points of measurements, the commissioning organization, together with the project and operational organizations, is developing a list of the necessary additional activities and directs it to the customer to take appropriate measures.
9.17. Prior to the implementation of additional activities, the zone of effective protection of underground structures remains reduced.
9.18. Adjusting the commissioning of the technical report on setting up ECH installations, which should include:
Full information about:
1) protected and adjacent underground structures;
2) existing sources of wandering currents;
3) criteria of corrosion hazard;
4) on constructed and previously operating (if there are such) ECH installations;
5) installed on the facilities of electric furnaces;
6) existing and newly constructed instrumentation;
7) electrically insulating compounds;
Full information about the work performed and its results;
- table with the final settings for the operation of the ECH installations;
- Table of potentials of protected structures in the established final modes of operation of the ECH installations;
- certificates (conclusions) of the owners of adjacent structures;
- conclusion on setting up ECH installations;
- Recommendations for additional measures to protect underground corrosion constructions.
10. The procedure for acceptance and commissioning of electrochemical protection installations
10.1. The ECH installations are put into operation after completion of commissioning and stability tests for 72 hours.
10.2. The ECH installation is commissioned by the Commission, which includes representatives of the following organizations: the customer; project (as needed); construction; The operational, on the balance of which will be transferred to the built ECH installation; Corrosion protection enterprises (protection services); Gosgortkhnadzor of Russia, the Russian State Energy Support Bodies of Russia (if necessary); Urban (rural) power grids.
10.3. Data of checking the readiness of objects to delivery The Customer reports to organizations that are part of the admission committee, not less than a day.
10.4. The customer presents the receiving commission: the project on the ECH device and the documents specified in the application y.
10.5. After familiarization with the executive documentation and technical report on commissioning works, the Reception Commission selectively verifies the implementation of the projected work - funds and nodes of ECH, including insulating flange compounds, measuring points, jumpers and other nodes, as well as the effectiveness of ECH installations. For this, the electrical parameters of the installations and the pipeline potentials are measured in areas where the minimum and maximum protective potential is recorded in accordance with the project, and the absence of positive potentials is provided during protection from the wandering currents.
ECH installations that do not correspond to project parameters should not be acceptable.
10.6. The ECH installation is put into operation only after signing the commission of acceptance Act.
If necessary, an acceptance of ECH can be carried out into temporary operation on the pipeline not completed construction.
After the end of the construction of ECH is subject to re-acceptance into continuous operation.
10.7. In case of accepting ECH on pipelines of thermal chain-free gaskets that have lacquered in the soils of more than 6 months, it is necessary to check their technical condition and if there are damage to establish the timing of their elimination.
10.8. Each accepted ECH installation assigns the sequence number and is given a special installation passport, which enters all acceptance test data (see Appendix F).
11. Operation of ECH installations
11.1. Operating control of ECH installations includes a periodic technical inspection, checking the effectiveness of their work.
On each protective installation, it is necessary to have a control log in which the results of inspection and measurements are entered (see Appendix X).
11.2. The maintenance of ECH installations during operation should be carried out in accordance with the schedule of technical inspections and planned-warning repairs. The graph of preventive inspections and planned-warning repairs should include the definition of species and volumes of technical inspections and repair work, the timing of their conduct, instructions on the organization of accounting and reporting on the work performed.
The main purpose of work on preventive inspections and planned-warning repairs is the content of ECH installations protection in a state of complete performance, preventing their premature wear and failures.
11.3. Technical inspection includes:
Inspection of all elements of the installation in order to identify external defects, checking the density of contacts, serviceability, the lack of mechanical damage to individual elements, the absence of subgars and traces of overheating, the absence of excavations on the track of drainage cables and the anode grounds;
- verification of fuses (if any);
- cleaning the body of the drainage and cathode converter, the joint protection unit outside and inside;
- measurement of current and voltage at the output of the converter or between galvanic anodes (treads) and pipes;
- measurement of the pipeline potential at the installation point of the installation;
- Production of entry in the installation log on the results of the work performed.
11.4. A technical inspection with testing performance includes:
All work on technical inspection;
- Measurements of potentials in constantly fixed reference points.
11.5. Current repair includes:
All technical inspection work with performance testing;
- measurement of insulation resistance of feed cables;
4.7 Operation of electrochemical protection installations
4.7.1 When operating the ECH installations, periodic technical inspections must be carried out and testing the effectiveness of their work.
On each protective installation, you must have a control log in which the results of inspection and measurements are entered.
4.7.2 Maintenance of ECH installations during operation should be carried out in accordance with the schedule of technical inspections and planned-warning repairs. The schedule of technical inspections and planned-preventive repairs should include the definition of species and volumes of inspections and repair work, the timing of their conduct, instructions on the organization of accounting and reporting on the work performed.
The main purpose of the work is the content of the installations of ECH protection in a state of complete performance, preventing their premature wear and failures.
4.7.3 Technical Inspection includes:
Inspection of all elements of the installation in order to identify external defects, checking the density of contacts, serviceability, the lack of mechanical damage to individual elements, the absence of subgars and traces of overheating, the absence of excavations on the track of drainage cables and the anode grounds;
Verification of fuse service;
Cleaning the body of the drainage and cathode converter, the joint protection unit outside and inside;
Measurement of current and voltage at the output of the converter or between the galvanic anode (protector) and the pipe;
Measurement of the polarization or total pipeline potential at the installation point of the installation;
Production of recording in the installation log on the results of the work performed.
4.7.4 Current Repair includes:
Measurement of insulation resistance of feed cables;
One or two of the following repairs: Power lines (up to 20% of the length), rectifier block, control unit, measuring unit, installation housing and mounting nodes, drainage cable (up to 20% of the length), contact device of the anodic earth circuit, contour Anodic grounding (in volume less than 20%).
4.7.5 Overhaul includes:
All work on technical inspection;
More than two repairs listed in paragraph 4.7.4, or repair in a volume of more than 20% - the power line, drainage cable, the outline of the anode ground.
4.7.6 An unscheduled repair is the type of repair caused by the refusal of the equipment and not provided for by the annual repairs plan.
The refusal of the equipment should be recorded by an emergency act, which indicates the causes of the accident and the defects to be eliminated.
Technical inspection - 2 times a month for cathode, 4 times a month - for drainage installations and 1 time in 6 months - for installations of galvanic protection (in the absence of telemechanical controls). In the presence of means of telemechanical control, the timing of technical inspections is established by the management of the operational organization, taking into account data on the reliability of telemechanic devices;
Current repair - 1 time per year;
Overhaul - depending on the operating conditions (approximately 1 time in 5 years).
4.7.8 In order to promptly perform unscheduled repairs and reduce breaks in the work of ECH in organizations operating ECH devices, it is advisable to have a backup fund of converters for cathode and drainage protection at the rate of 1 reserve converter to 10 valid.
4.7.9 When checking the parameters of the electrode protection, the drainage current is measured, there are no current in the drainage chain when the polarity of the pipeline is changed relative to the rails, the threshold of the drainage is determined (if there is a relay in the drainage circuit or control circuit), as well as resistance in the electrical circuit.
4.7.10 When checking the parameters of the cathode station, the cathode protection current is measured, the voltage at the output terminals of the cathode station and the potential of the pipeline on the contact device.
4.7.11 When checking the settings for installing galvanic protection, measure:
1) current strength in the chain galvanic anode (ha) - protected structure;
2) the potential difference between ha and pipe;
3) Pipeline potential at the point of connecting hectares when connected hectares.
4.7.12 ECH effectiveness check no less than 2 times a year (with an interval of at least 4 months), as well as when changing the parameters of the ECH installations and with changes in corrosion conditions associated with:
Laying new underground structures;
Changing the configuration of the gas and rail network in the protection zone;
Installing ECH on adjacent communications.
4.7.13 Monitoring the effectiveness of EHR underground steel pipelines is made according to the polarization potential or in the absence of the possibility of its measurements - according to the total pipeline potential at the point of connection of the ECH installation and at the boundaries of the protection zones created by it. To connect to the pipeline, control and measurement points, inputs in buildings and other pipeline elements available for measurement production can be used. On the pipeline to the connection site there should be no flange or electrically insulating compounds if electrical jumpers are installed on them.
4.7.14 The polarization potential of steel pipelines is measured on stationary piles equipped with a long-acting media uniform electrode with a potential sensor - auxiliary electrode (VE, Fig. 4.7.1), or on non-stationary piles with a portable media uniform comparison electrode with a potential sensor - auxiliary electrode (VE, Fig. 4.7.2).
Fig.4.7.1 Scheme of measuring polarization potential on stationary piles
1 - pipeline; 2 - control conductors; 3 - type 43313.1 type; 4 - stationary media uniform comparison electrode; 5 - potential sensor.
Note:
Fig.4.7.2 Scheme of measurement of polarization potential on nonstationary piles
1 - pipeline; 2 - potential sensor; 3 - portable media uniform comparison electrode; 4 - Type 43313.1
Note:
When using a DPK-02 type device, the conductor from the pipeline is attached to the appropriate terminal of the device.
4.7.15 For measuring the polarization potential on nonstationary piles, VE and a portable media uniform comparison electrode are used, mounted at the measurement time in a special shurfe.
The preparation of the shurph and the installation of the WE is produced in the following order:
In the intended point of measurement (where there is the ability to connect to the pipeline) using the trail or by bindings on the plan of the pipeline route, the location of the pipeline is determined.
Over the pipeline or in the maximum approximation to it at the absence of a road surface, a shurt is a depth of 300-350 mm and a diameter of 180-200 mm.
Sensor (VE) and a portable comparison electrode should be installed at a distance of at least 3 h. from tubes of hydraulic shutters, condensate collectors and control tubes ( h. - distance from the surface of the Earth to the upper generator pipeline).
Before installing in the soil, WE is cleaned with a sanding with a grinding (GOST 6456-82) with a graininess of 40 and less wipe. Previously, from the bottom of the shurph, a part of the soil in contact with WE should be removed solid inclusions of more than 3 mm. A layer of soil with a thickness of 30 mm is poured on the lined bottom of the shurt. Then lay the WE working surface down and fall asleep with its soil to 60-80 mm from the bottom of the shurt. The soil over WE is rambling with an effort of 3-4 kg to the Vuel area. From above install a portable comparison electrode and fall asleep with soil. The portable electrode comparison before installation is prepared by paragraph 4.2.12. In the presence of atmospheric precipitations, there are measures against moisturizing soil and moisture in the Shurf.
4.7.16 To measure the polarization potential, devices with a current interrupter use (for example, type 43313.1 or PKI-02).
Current interrupter provides an alternate connection of the VE to the pipeline and to the measuring circuit.
Measurements on stationary and non-stationary piles are made as follows. To the appropriate terminals of the devices (Fig. 4.7.1 and 4.7.2) attribute control conductors from the pipeline, VE and the comparison electrode; Include the device. 10 minutes after the instrument is turned on, the potentials are measured with the results of the results every 10 s or when using the PKI-02 instrument - with storage in the device's memory. Duration of measurements in the absence of wandering currents at least 10 minutes. If there are wandering currents, the measurement duration is assumed in accordance with the recommendations set out in paragraph 4.2.13.
Measurement results are entered into the protocol (application C).
Notes:
1. Duration of measurements of the pipeline potential at the point of connecting the protection installation during its technical inspection (see clause 4.7.3) can be 5 minutes.
2. If at the stationary Cipe WE is constantly connected to a cathode polarizable pipeline, then measurements of polarization potential begins immediately after connecting the instrument.
4.7.17 The average value of polarization potential E. cf. , B, calculated by the formula:
,
where E. i. - The sum measured n. values \u200b\u200bof polarization potentials (B) for the entire measurement period;
n. - Total number of measurements.
4.7.18 At the end of the measuring work on nonstationary, and extraction of the electrode of the comparison electrode and VE, the shurf fall asleep. In order to ensure the possibility of repeated measurements at this point on the plan of the pipeline laying make the measurement item binding.
4.7.19 To determine the effectiveness of ECH in total potential (comprising polarization and ohmic components), devices of type eV 2234, 43313.1, PKI-02 are used. Portable comparison electrodes are installed on the surface of the Earth at the lowest distance (in plan) from the pipeline, including at the bottom of the well. Measurement mode - according to claim 4.7.15.
4.7.20 The average value of the total potential U. cf. (C) calculated by the formula:
,
where U. i. - the sum of the values \u200b\u200bof the total potential, n. - Total number of counts.
Measurement results are recorded in a summary (Appendix C), and can also be fixed on underground pipeline circuits.
4.7.21 When protecting on a softened security criterion is minimal (by absolute value), the protective polarization potential is determined by the formula:
E. min. = E. art - 0.10 V,
where E. art - stationary potential of the auxiliary electrode (potential sensor).
Polarization potential is measured in accordance with clause 4.7.15.
For determining E. art Sensor (VE) The sensor is disconnected from the pipe and 10 minutes after the disconnection, its potential is measured. E.. If the measured potential is negative - 0.55 V, then this value is taken for E. art . If the measured potential in absolute value is or less than 0.55 V, then it is accepted E. art \u003d -0.55 V values E. art (Measured and accepted) are recorded in the Protocol (application C).
4.7.22 When the inefficient operation of the cathode or drainage installations is detected (their actions are reduced, the potentials differ from permissible protective) it is necessary to regulate the operation mode of the ECM installations.
If the pipeline potential on the connection area of \u200b\u200bthe galvanic anode (ha) will be less (by the absolute value) of the design or minimum protective potential, it is necessary to test the serviceability of the connecting wire between the hea and the pipeline, its soldering places to the pipeline and hectares. If the connecting wire and the spike location will turn out to be in good condition, and the potential at an absolute value does not increase, then they make a shurf to the depth of the heap of hea for inspection and checking the presence of backfilling around it (activator).
4.7.23 Resistance to spreading current anodic grounding should be measured in all cases where the operating mode of the cathode station changes dramatically, but at least 1 time per year.
The impedance to spread the anode grounding current is determined as a private from dividing the voltage at the output of the cathode installation at its output current or using the M-416 device and steel electrodes according to the scheme in Fig. 4.7.3.
Fig.4.7.3 Measurement of resistance to spreading current anode grounding
1 - anodic grounds; 2 - instrumentation; 3 - measuring instrument;
4 - measuring electrode; 5 - feed electrode; 6 - drainage wire.
With the length of the anode earthing l. a.Z. The feed electrode is relating to the distance b. 3. l. a.Z. , measuring electrode - for distance a. 2. l. a.Z.
4.7.24 The resistance of the protective grounding of electrical installations is measured at least 1 time per year. The diagram of measuring the resistance to spreading the current grounding current is shown in Fig. 4.7.3. Measurements should be performed in the most dry season.
4.7.25 The serviceability of electrically insulating compounds is checked at least once a year. For this purpose, special certified quality indicators of electrically insulating compounds are used.
In the absence of such indicators, the voltage drops on the electrically insulating connection or synchronously the potentials of the pipe on both sides of the electrically insulating compound are measured. Measurement is carried out with two malelvoltmeters. With a good electrically insulating connection, the synchronous measurement shows the potential jump.
In the application of insulating inserts of CJSC "; Ecokaz"; (G.Vladimir), having a metal coupling, isolated on both sides from the pipeline, check their condition can be determined by the coupling resistances relative to each side of the pipeline using a stress megommeter to 500 V. Resistance must be at least 200 com.
The results of the verification are issued by protocols according to the annex C.
4.7.26 If there were 6 or more failures in the operation of the transmitter during the current installation of ECHs during the year, the latter is subject to replacement. To determine the possibility of further use of the converter, it is necessary to test it in the amount provided for by the requirements of the preset control.
4.7.27 In the event that during the operation of the ECH installation, the total number of failures in its operation will exceed 12, it is necessary to conduct a survey of the technical condition of the pipeline along the entire length of the protective zone.
4.7.28 Organizations operating ECH devices should annually compile a report on denials in their work.
4.7.29 The total duration of interruptions in the operation of ECH installations should not exceed 14 days during the year.
In cases where the protective potential of the pipeline is provided in the action zone of the ECH installation, the protection potential of the pipeline is provided by adjacent ECH (overlapping protection zones), the malfunctional is determined by the operational organization's manual.
4.8 Operational control of the state of isolation and risk of corrosion pipelines
4.8.1 In all shurts beloved during the repair, reconstruction and liquidation of insulation defects or corrosion damage to the pipeline, the corrosion state of the metal and the quality of the insulating coating should be determined.
4.8.2 When corrosion damage is detected on the current pipeline, a survey is carried out in order to identify the cause of corrosion and the development of anti-corrosion events.
The form of an act of examination is approved by the head of the economy operating this pipeline.
The act should be reflected:
The year of commissioning of this section of the pipeline, the diameter of the pipeline, the wall thickness, the depth of laying;
Type and material of insulating coating;
Coating condition (damage);
Thickness, transition resistance, coating adhesion;
Corrosion aggressiveness of the soil;
The presence of a dangerous action of wandering currents;
Information about the date of inclusion of protection and data on the disconnects of ECHS;
Measurement data of the polarization potential of the pipe and the potential of the pipe when the protection is turned off;
The condition of the outer surface of the pipe near the place of damage, the presence and nature of corrosion products, the number and size of damage and their location around the perimeter of the pipe.
When a high corrosion aggressiveness of the soil or a hazardous action of wandering currents during a shurn-free survey should additionally determine the corrosive aggressiveness of the soil and the presence of a dangerous action of wandering currents at a distance of about 50 m on both sides of the place of damage along the pipeline route.
In conclusion, the cause of corrosion should be indicated and anti-corrosion events proposed.
The possible form of an act is given in Appendix Sh.
4.8.3 Determination of the hazardous action of wandering currents (according to PP.4.2.16-4.2.24) in the plots of pipelines that have not previously demanded the ECH, is carried out 1 time in 2 years, as well as with each change in corrosion conditions.
4.8.4 Assessment of the corrosion aggressiveness of the soils (according to pp.4.2.1-4.2.8) on the highway of pipelines, previously not demanded by ECH, is carried out 1 time in 5 years, as well as with each change in corrosion conditions.
4.8.5 In the area of \u200b\u200bthe pipeline where corrosion damage occurred, after its liquidation it is advisable to provide for the installation of corrosion indicators (clause 4.3.11 and annex O).
Applications
Appendix A.
(Reference)
SCROLL
regulatory documents on which there are references in this Instruction
1. GOST 9.602-89 *. Unified corrosion and aging protection system. Underground facilities. General requirements for corrosion protection. Considering being № 1.
2. GOST R 51164-98. Main steel pipelines. General requirements for corrosion protection.
3. GOST 16336-77 *. Polyethylene compositions for cable industry. Technical conditions.
4. GOST 16337-77 * E. High pressure polyethylene. Technical conditions.
5. GOST 9812-74. Petroleum bitumens. Methods for determining water saturation.
6. GOST 11506-73 *. Petroleum bitumens. Method for determining the softening temperature by ring and ball.
7. GOST 11501-78 *. Petroleum bitumens. The method of determining the penetration depth of the needle.
8. GOST 11505-75 *. Petroleum bitumens. Method for determining extensibility.
9. GOST 15836-79. Mastics bitumen rubber insulating.
10. GOST 2678-94. Materials Roll roofing and waterproofing. Test methods.
11. GOST 19907-83. Electro insulating fabrics from glass twisted complex threads.
12. GOST 12.4.011-89. SSBT Means of protecting working. General requirements and classification.
13. GOST 6709-72. Distilled water.
14. GOST 19710-83E. Ethylene glycol. Technical conditions.
15. GOST 4165-78. Copper sulfate 5-water. Technical conditions.
16. GOST 5180-84. Soils. Methods of laboratory definition of physical characteristics.
17. GOST 6456-82. Grinding sandpaper paper. Technical conditions.
18. Security rules in the gas economy (PB 12-245-98). M.: NPO OUT, 1999
19. Snip 11-01-95. Instructions on the procedure for developing, coordination, approval and composition of project documentation for the construction of enterprises, buildings and structures.
20. Rules of electrical installation devices (PUE). 6th edition. M.: CJSC "; Energo";, 2000
21. Rules for the operation of consumer electrical installations (PEEP) of the mainergradzor of Russia.
22. Safety regulations for the operation of consumer electrical installations (PTBEEP) of the mainergradzor of Russia.
23. TU 1394-001-05111644-96. Steel pipes with two-layer coating of extruded polyethylene.
24. TU 1390-003-01284695-00. Steel pipes with an outer coating of extruded polyethylene.
25. TU 1390-002-01284695-97. Steel pipes with an outer coating of extruded polyethylene.
26. TU 1390-002-01297858-96. Steel pipes with a diameter of 89-530 mm with an outer anti-corrosion coating of extruded polyethylene.
27. TU 1390-003-00154341-98. Steel electric welded pipes and seamless with outer two-layer anti-corrosion coating based on extruded polyethylene.
28. TU 1390-005-01297858-98. Steel pipes with outer two-layer protective coating based on extruded polyethylene.
29. TU RB 03289805.002-98. Steel pipes with a diameter of 57-530 mm with an outer two-layer coating based on extruded polyethylene.
30. TU 1394-002-47394390-99. Steel pipes with a diameter of 57 to 1220 mm coated with extruded polyethylene.
31. TU 1390-013-04001657-98. Pipes with a diameter of 57-530 mm with an outer combined tape-polyethylene coating.
32. TU 1390-014-05111644-98. Pipes with a diameter of 57-530 mm with an outer combined tape-polyethylene coating.
33. TU RB 03289805.001-97. Steel pipes with a diameter of 57-530 mm with an outer combined band-polyethylene coating.
34. TU 4859-001-11775856-95. Steel pipes with plated polymer sticky tapes.
35. TU 2245-004-46541379-97. Ribbon heat-resistant two-layer radiation-known "; Donrad";.
36. TU 2245-002-31673075-97. The tape is thermal sung double-layer radiation-known "; DRL";.
37. TU 2245-001-44271562-97. Ribbon protective thermal suite "; term";.
38. TU RB 03230835-005-98. Tapes heat supreme two-layer.
39. TU 8390-002-46353927-99. Little non-woven thermopower technical.
40. TU 8390-007-05283280-96. Little nonwoven glued for technical purposes.
41. TU 2245-003-1297859-99. Polyethylene tape for the protection of oil gas pipelines "; Pollen";.
42. TU 2245-004-1297859-99. Wrapper polyethylene to protect oil-gas pipelines "; polilan - about";.
43. TU 38.105436-77 S M № 4. The canvas rubber waterproofing.
44. TU 2513-001-05111644-96. The mastic is a bitumen-polymer for insulating coatings of underground pipelines.
45. TU 2245-001-48312016-01. Ribbon polymer-bituminous based on mastic "; transcor"; - Lithor.
46. \u200b\u200bTU 2245-024-16802026-00. Liam-M tape (modified) for insulation of underground gas pipelines.
47. TU 5775-002-32989231-99. Mastic Bituminous-polymer isolation "; transcor";.
48. TU 204 RSFSR 1057-80. Coating protective bitumen-atactic from underground corrosion of steel gas and plumbing networks and liquefied gas storage containers.
Working programm7 Vladimir 2005 1 Preface The purpose of the discipline "Automation of systems ... detection of hidden ( underground) Leaks outdoor ... worn gas pipelines. " 9.13. Instructionbyprotectionurbanpipelinesfromcorrosion. RD153 -39 .4-091 -01 9.14. GOST 9.602 ...
Code of Projecting and Construction Rules Design and construction of gas pipelines made of metal pipes Designing and Construction of Gas Pipelines from Metal Pipes Preface
Document05-27 Preface 1 ... protection undergroundpipelinesfromcorrosion TU ... RD153 -39 .4-091 -01 Instructionbyprotectionurbanunderground Gas pipelines RD 12-411-01 Instructionby underground Steel gas pipelines RD ...
Arrangement of the Rules for Design and Construction Design and Construction of gas pipelines made of metal pipes Preface
Document27 Preface 1 ... protection undergroundpipelinesfromcorrosion ... 153 -39 .4-091 -01 Instructionbyprotectionurbanunderground gas pipelines S M12291 1200025080ird 12-411- 01 Instructionby Diagnosing a technical condition underground Steel Azo Studies S. RD ...
Self-regulatory organization Non-profit partnership "Association of organizations carrying out the preparation of project documentation of energy facilities of networks and substations" Energoproekt "
DocumentEnergy by status on 01 .01 .2012. Content Preface Appendix ... -98 * Pipelifiers Steel trunk. General requirements K. protectionfromcorrosion. 23 ... RD 34.03.211) Instructionby safety technician when conducting fasteners in underground ...
7 Requirements for maintenance and repair of ECH installations during operation
7.1 Maintenance and repair of ECH installations during operation are carried out for their content in the state of complete performance, prevention of premature wear and failures and are carried out in accordance with the maintenance schedule and planning and preventive repair.
7.2 Schedule of maintenance and planned-warning repairs should include the definition of species and volumes of maintenance and repair work, the timing of their implementation, instructions on the organization of accounting and reporting on the work performed
7.3 On each protective installation, you must have a control log in which the results of the inspection and measurements are entered, the Appendix J.
7.4 Maintenance and Planning and Warning Repairs are held:
maintenance - 2 times a month for cathode, 4 times a month - for drainage installations and 1 time in 3 months - for electroplating installations (in the absence of telemechanical controls). In the presence of means of telemechanic control, the timing of technical inspections is established by the management of the OETS, taking into account data on the reliability of telemechanic devices;
maintenance with performance test - 1 time in 6 months;
current repair - 1 time per year;
overhaul -1 every 5 years
inspection of all elements of the installation in order to identify external defects, checking the density of contacts, serviceability, the lack of mechanical damage to individual elements, the absence of subgars and traces of overheating, the absence of excavations on the track of drainage cables and the anode grounds;
checking the health of the fuses (if available);
cleaning the body of the drainage and cathode converter, the joint protection unit outside and inside;
measurement of current and voltage at the output of the converter or between galvanic anodes (treads) and pipes;
measurement of the pipeline potential at the installation point;
production of entries in the installation log on the results of completed work;
elimination of defects and malfunctions identified during the inspection process that do not require additional organizational and technical events.
all work on technical inspection;
measurements of potentials in constantly fixed reference points.
7.7 Current Repair includes:
all technical inspection work with performance testing;
measurement of insulation resistance of feed cables;
one or two of the following works: repair of power lines (up to 20% of the length), repair of the rectifier block, repair of the control unit, repair of the measuring unit, repairing the installation of the installation and attachment sites, repairing the drainage cable (up to 20% of the length), repair of the contact device The contour of the anode grounding, the repair of the outline of the anode grounding (in the amount of less than 20%).
all work on technical inspection with the effectiveness of ECH effectiveness;
more than two works from the list of repairs listed in paragraph 7.7 of this standard, or repair in the amount of more than 20% - length of the power line, drainage cable, the outline of the anode ground.
7.10 In order to promptly perform unscheduled repairs and reduce breaks in the work of ECH in organizations operating the ECH devices, there should be a reserve fund of converters for cathode and drainage protection at the rate of - 1 backup transducer on 10 valid.
8 Requirements for the methods of controlling the effectiveness of the ECH installations during operation.
8.1 Control of the effectiveness of ECH pipelines of thermal networks are no less often than 2 times a year (with an interval of at least 4 months), as well as when changing the parameters of the ECH installations and when changing corrosion conditions associated with:
laying new underground structures;
due to repair work on thermal networks;
installing ECH on adjacent underground communications.
8.2 When checking the parameters of the electrodynate protection, the drainage current is measured, there are no current in the drainage chain when the polarity of the pipeline is changed relative to the rails, the threshold of the drainage is determined (if there is a relay in the drainage chain or control circuit), as well as resistance to the electrical circuit.
8.3 When checking the parameters of the cathode station, the cathode protection current is measured, the voltage at the output terminals of the cathode station and the potential of the pipeline on the contact device.
8.4 When checking the settings for installing electroplating protection (when the protector is located in channels or cameras) measure:
current strength in chains between protector sections and pipelines;
the magnitude of the displacement of the potential difference between the pipeline and the measuring electrodes before and after connecting the sections of the protector to the pipelines.
babe-free and channel gaskets with the placement of AZ outside the channel are carried out by the potential difference between the pipeline and MES installed in a stationary or nonstationary pile (in the latter case using portable MES).
8.6 The scheme of the portable MES is shown in Figure 4 of Appendix A ST-117-2007 "Pipelines of heat networks. Corrosion protection. Creating conditions. The norms and requirements, the scheme and technical characteristics of MES type Enes and ESN-MS, installed in stationary instrumentation, are shown in the POST-117-2007 "pipelines of thermal networks. Corrosion protection. Creating conditions. Norms and requirements. "
8.7 Stationary piles should be installed in the sections of heat networks, where the minimum and maximum permissible values \u200b\u200bof protective potentials are expected, in places intersection of thermal networks with rails of electrified transport
8.8 In the absence of stationary boiled, portable MES is installed on the surface of the earth between pipelines (in terms of), at the bottom of the thermal chamber (if there is water in it). Before installing the electrodes, the soil must be loosened to a depth of 4-5 cm and solid inclusions of more than 3 mm should be removed from it. If the soil is dry, it should be moistened to the total water saturation of tap water. For measurements, devices of type EV 2234, 43313.1, PKI-02 are used.
8.9 Duration of measurements in the absence of wandering currents should be at least 10 minutes with continuous registration or with manual recording of results every 10 seconds. With the presence of wandering currents, the tram with a frequency of 15-20 pairs per hour of measurement should be carried out during the watches of the morning or evening peak load of electrical transport.
In the zone of the influence of the wandering currents of electrified railways, the measurement period should cover the starting moments and the time of passing the electric trains in both sides between the two nearest stations.
8.10 The values \u200b\u200bof the potential difference between pipelines and MES in the protection area can be in the range of minus 1.1 to minus 3.5 V.
8.11 The average value of the potential difference U CP (B) is calculated by the formula:
U CP \u003d U I / N, (8.1)
where u i is the sum of the values \u200b\u200bof the potential difference; N is the total number of counts.
Measurement results are entered into the protocol (application and this standard), and also fix on thermal network circuits.
8.12 When the inefficient operation of the cathode or drainage installations is detected (the zones of their action are reduced, the potentials differ from permissible protective) It is necessary to regulate the mode of operation of the ECM installations.
8.13 The abstraction of the AZ current to spread in all cases where the operating mode of the cathode station changes dramatically, but at least 1 time per year. The resistance to the spreading current AZ is determined as a private from dividing the voltage at the output of the cathode installation at its output current or at the location of AZ outside the channel using M-416, F-416, F 4103-M1 devices and steel electrodes according to the scheme shown in Fig. 1. Measurements should be performed in the most dry season. Drainage wire (6) for measurement time should be disabled. With the length of the LAA, the feed electrode (5) is referred to a distance in 3LAs, auxiliary electrode (4) - at a distance A 2LA.
1 - anodic grounds; 2 - instrumentation; 3 - measuring instrument; 4 - auxiliary electrode; 5 - feed electrode; 6 - drainage wire.
Figure 1 - Measuring resistance to anodic grounding
At the arrangement of Az in the channels, the resistance to spreading the current AZ is determined by flooding or changing the channel to the level of the insulating structure of the pipes. If there is a few shoulders of AZ, their resistance to spreading current is determined separately.
8.14 Control of the effectiveness of ECH funds on pipelines of heat networks of the channel gasket at the arrangement of AZ and electroplating anodes (protector) directly in the channels, is carried out by the value of the potential difference between the pipeline and installed on its surface (or thermal insulation) WE in the direction of negative values \u200b\u200bwithin from 0.3 to 0.8 V.
In ECH, with the help of protectors from the magnesium alloy, the displacement of the potential difference between the VE and the pipeline should be at least 0.2 V.
8.15 Before the start of measuring operations in a given ECH zone, the levels of flooding of a channel and chambers are determined if there is a visually or instrumental method. In the latter case, the level of flooding is determined by the reaches of the IE installation items on the supply and return pipelines - at the level of the lower forming heat insulating structure.
8.16 Checking the presence of water at the installation level of the WE is made in such a sequence:
Disconnect the cathode protection stations (the protectors are not turned off when applying them);
The megaometer is connected to the conductor from the pipeline on the piping at the piping and WE;
When the jumper is removed on the piping between the pipeline and VE measure the electrical resistance R.
The value of R 10.0 kΩ indicates the presence of water in the channel (camera) at the installation level of the IE or above it.
Similar measurements are produced in other paragraphs where VEs are installed.
8.17 Measuring the potential of pipelines with respect to the VE in areas where the channel flooding at the installation level of the VE or above it (after the technical inspection of ECH installations) is made in such a sequence:
When the SCZ is turned off, connect the voltmeter to the checkpoint terminals: the positive clamp of the voltmeter is to the terminal "T" (pipeline), negative to the terminal of the rolling electrode. For measurements, a voltmeter with an input resistance is not lower than 200 kΩ per 1.0 to the instrument scale (type 43313.1 multimeter, eV 2234 type voltammermeter). The toggle switch or jumper must be open.
No less than 30 minutes after disconnecting the SCZ to fix the initial value of the potential difference between the pipeline and VE (IX), taking into account the polarity (sign).
Turn on the SCZ by setting the mode of its operation at minimum values \u200b\u200bof current and voltage.
An increase in current force in the chain of the SCZ to establish its value when the potential difference is reached between the pipeline and VE: and 'T-VE. In the range of minus 600 to minus 900 mV (no earlier than 10 minutes after setting the value of the current for the current).
Calculate both T-VE. Taking into account and Ex.
And T-VE. \u003d I T-VE. - I isch. , mV.
Example of calculation number 1 .
I isch. \u003d -120 mV, and 'T-VE. \u003d -800 mV.
And T-VE. \u003d -800 - (-120) \u003d -680 mV.
Example of calculation number 2 .
I isch. \u003d +120 mV, and 'T-VE. \u003d -800 MV.
And T-VE. -800 - (120) \u003d -920 mV.
8.18 If the obtained values \u200b\u200band T-VE. At the instrument of protection area zones (in the sections of flooding or driving, the soil) are not within the value of minus 300 -800 mV, the current of the transducer current is adjusted.
Note. An increase in the current strength of the converter should be carried out taking into account the maximum allowable voltage value at the output of the converter equal to 12.0 V.
8.19 At the end of the measuring papers, if the VE is made of carbon steel, produce a closure of VE with a pipeline. If VE is made of stainless steel, WE with pipeline does not closure.
8.20 In case of faults of VE (damage to the conductors, mounting to the VEU pipeline), the available points are installed at the surface of the heat-insulating structure of the portable VE, with which the measuring work outlined above is produced.
8.21 When the sections of pipelines that are not susceptible to flooding and not contact with the ground, the specified area (shoulder) is appropriate to turn off from the ECH system from the ECH system until the channel is detected in this area. After disconnecting the specified area, additional adjustment of the operation of the SCZ is required. It is advisable to convert the SCZ, applying the device to automatically turn on or disconnect the SCs (or individual sections of pipelines), depending on the level of channel flooding in these areas.
8.22 Monitoring the effectiveness of ECH using electroplating anodes (protector) from magnesium alloys placed at the bottom or channel walls is carried out after the work specified in paragraphs 8.15-8.16 of this Standard.
8.23 When fixing the flooding of the channel on the installation section of the WE, the action of the protector protection measurement is checked:
Current forces in the link chain (group) "Protectors - Pipeline";
The potential of the tread or a group of protector disconnected from the pipeline relative to the copper-grinding electrode of the comparison installed at the bottom of the channel (if possible) or above the channel in the installation zone of the controlled group of protector;
Potential of the pipeline with respect to WE with a disabled and included group of prototors. Data is entered into the Protocol given in Appendix to this Standard.
Measurements of these parameters are produced only if there is a possibility of disconnecting the group of protector from pipelines and connecting measuring instruments.
The presence of a current in the chain "Protectors - Pipeline" indicates the integrity of the specified chain;
The potentials of the protector disconnected from the pipeline, the values \u200b\u200bof which (by absolute value) are not lower than 1.2 V, characterize the protectors, as good (the potentials of the protector are measured only in the presence of electrolytic contact of the testers with electrolyte - water at the bottom of the channel);
The potential difference between the pipeline and the VE with the on and off of the protector group is incorporated at least 0.2 V, characterizes the efficiency of the test protection of pipelines.
8.24 Direct assessment of the risk of corrosion and effectiveness of the EKHZ pipelines of thermal networks of the channel gasket and on the sections of their laying in cases can be made using corrosion indicators of the BPI-1 or BPI-2 type. The essence of the method of direct assessment of the risk of corrosion and the effectiveness of ECH, data processing methods during the survey of the surface of the BPPI-1, when the BPPI-2 is triggered in section 11 ST-117-2007 "Thermal network pipelines. Corrosion protection. Creating conditions. Norms and requirements »
8.25 The serviceability of the EIS is tested at least 1 time per year. For this purpose, special certified quality indicators of electrically insulating compounds are used. In the absence of such indicators, the voltage drops on the electrically insulating connection or synchronously the potentials of the pipe on both sides of the electrically insulating compound are measured. Measurements are carried out with two millivoltmeters. With a good electrically insulating connection, the synchronous measurement shows the potential jump. The results of the inspection are drawn up by the protocol according to the application of L of this Standard.
8.26 If there was six or more failures in the operation of the converter during the year on the current installation of the ECH, the latter is subject to replacement. To determine the possibility of further use of the converter, it is necessary to test it in the amount provided for by the requirements of the preset control.
8.27 In the case of the entire time of operation of the ECH installation, the total number of failures in its operation will exceed 12, it is necessary to examine the technical condition of pipelines along the entire length of the protective zone.
8.28 Total If the duration of interruptions in the operation of the ECH installations should not exceed 14 days during the year.
8.29 In cases where the protective potential of the pipeline is provided in the action of the installation of the ECH, the protective potential of the pipeline is provided by adjacent ECH installations (overlapping protection zones), then the malfunctional period is determined by the operational organization's manual.
8.30 Organizations operating ECH installations should annually compile a report on refusals in their work.
9 Requirements for the organization of control and maintenance of protective coatings during operation
9.1 In the process of operation of protective coatings of pipelines of thermal networks, periodic monitoring of their state is carried out.
9.2 Control and maintenance is mandatory, protective coatings of thermal networks of heat networks located at affordable areas are subject to:
Overhead pad pipelines;
Pipelines in thermal chambers;
Pipelines in passing channels and manifolds;
Pipelines in viewing wells.
9.3 Monitoring the condition of protective coating of pipelines of thermal networks located in non-projective, semi-pass channels as well as pipelines of thermal networks of the infantal gasket is carried out during control openings of thermal networks. Maintenance and repair of coatings on these areas of pipelines are carried out in emergency repairs
9.4 Methods for checking quality indicators and eliminated detected defects for protective coatings in the field are shown in section 9 ST-117-2007 "Thermal network pipelines. Corrosion protection. Creating conditions. Norms and requirements. "
9.5 Choosing a protective coating for repairs is determined by the assignment * of heat pipelines (main thermal networks, quarterly (distribution) thermal networks ) and types of work carried out, which are aimed at ensuring the operational reliability of thermal networks, Table 1.
9.6 The quality of protective anti-corrosion coatings applied in the process of performing repair work is checked with the preparation of acts of hidden work and with the introduction of quality control results in the production of anti-corrosion work according to Annex M of this Standard
Types of protective coatings
Table 1
| Purpose of thermal networks and the type of recommended coatings |
|||
| Types of work carried out on thermal networks | Main thermal networks | Central heating networks | Hot water networks |
| Anticorrosion protection of newly constructed thermal networks | Paint and varnish Silicate email ** Metalization ** Aluminocheramic ** | Paint and varnish | Paint and varnish Cyilicate empty ** |
| Anticorrosive protection during the reconstruction and overhaul of thermal networks | Paint and varnish Silicate email ** Metalization ** Aluminocheramic ** | Paint and varnish | Paint and varnish Cyilicate empty ** |
| Anticorrosion protection at current repair and liquidation of thermal network damage | Paint and varnish | Paint and varnish | Paint and varnish |
Notes.
* As part of this standard, the following separation of heat networks is applied depending on their purpose:
main thermal networks serving major residential areas and groups of industrial enterprises - from heat source to CTP or ITP;
quarter (distribution) thermal networks(Hot water supply systems and central heating systems) serving a group of buildings or an industrial enterprise - from CTP or ITP before joining individual buildings.
** When using these coatings, the subsequent anti-corrosion protection of welded joints and elements of pipelines of thermal networks with paint and varnishes.
10 Safety requirements when working with protective anti-corrosion
coatings and during the operation of electrochemical protection devices
10.1 The performance of work on the protection of pipelines of the heat network from external corrosion using protective anti-corrosion coatings should strictly follow the requirements of the security provided in the technical conditions for anti-corrosion materials and protective anti-corrosion coatings, GOST 12.3.005-75, GOST 12.3.016-87, and Also in existing regulatory documents.
10.2C. Only persons trained in safe work techniques that have passed on to the pipes trained in safe work techniques that have passed on to the tubes of protective anti-corrosion coatings can be allowed.
10.3 The worker staff should be aware of the degree of toxicity of applicable substances, methods of protection against their impact and measures for first aid for poisoning.
10.4 With the use and testing of protective anti-corrosion coatings containing toxic materials (toluene, solvent, ethyl cellosolve, etc.), the rules for safety and industrial sanitation, sanitary and hygiene requirements for industrial equipment in accordance with the current regulatory documents should be respected
10.5 Conducting harmful substances in the air of the working area when applying protective anti-corrosion coatings on pipes should not exceed the MPC, according to GOST 12.1.005-88:
toluene - 50 mg / m 3, solvent - 100 mg / m 3, aluminum - 2 mg / m 3, aluminum oxide - 6 mg / m 3, ethyl cellosolv - 10 mg / m 3, xylene - 50 mg / m 3, gasoline - 100 mg / m 3, acetone - 200 mg / m 3, White spirit - 300 mg / m 3,
10.6All operations associated with the application of protective anti-corrosion coatings containing toxic substances should be carried out in the shops equipped with supply and exhaust and local ventilation in accordance with GOST 12.3.005-75.
10.7The works with protective anti-corrosion coatings containing toxic substances should be used individual means of protection against toxic substances to the skin, on the mucous membranes, in the respiratory and digestion organs according to GOST 12.4.10-89 and GOST 12.4.103-83.
10.8 In the production of installation, repair, repair, installation of ECH installations and electrical measurements, it is necessary to comply with the requirements of GOST 9.602, the rules of production and acceptance of work, sanitary and hygienic requirements.
10.9 The main inspection of the ECH installations must be disconnected by the supply network voltage and the drainage circuit is open.
10.10 During the entire period of operation of the experimental station of cathode protection, included for the test period (2-3 hours), the index of the anode earthing should be on duty, not allowing unauthorized persons to the anode earthing, and warning signs must be established in accordance with GOST 12.4. 026 -76.
10.11 Include electrochemical protection of pipelines of thermal networks with the location of the anodic gaps directly in the channels, the DC voltage at the output of the cathode protection station (transducer, rectifier) \u200b\u200bshould not exceed 12 V.
10.12 On the areas of pipelines of heat networks to which the cathode protection station is connected, and the anode earthingers are installed directly in the channels, placles with the inscription "Attention!" Were installed under the covers of heat chambers. Catodic protection operates in the channels. "
Requirements for the production of production and consumption waste generated when protecting pipelines of thermal networks from external corrosion
11.1 The production of production and consumption, resulting in the protection of pipelines of thermal networks from external corrosion at the stage of acceptance and operation, should be considered:
Materials used in the production of anticorrosive coatings and lost their consumer properties (paints, solvents, hardeners);
Wires of non-ferrous metals used in the production of electrochemical protection devices and losing their consumer properties.
11.2 The procedure for treating waste generated by protecting pipelines of thermal networks from external corrosion is determined in accordance with the section "Requirements for the production of production and consumption waste at the construction and operation stages" ST-118A-02-2007 "Heat Systems. Delivery conditions. Norms and requirements. "
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