Maintenance of valves. Repair of fittings and pipelines
Faulty fittings are inspected, determining the possibility of repair on site. If this is not possible, partial or complete dismantling is carried out. In the absence of new fittings, a sliding insert is installed in place of the dismantled one, which allows not to interrupt the water supply to consumers.
The expandable insert consists of flanges with threaded sockets, a coupling and locknuts. But more often, instead of a removed valve, they put a "coil" consisting of two flanges with a pipe segment welded between them along the length of the valve.
When repairing valves, they eliminate water leakage through the gland seal (gland), cracks or defects in the body, loose shutoff of the water flow (the fittings “do not hold”), leakage at the junctions with pipelines.
Leakage through the stuffing box seal is eliminated by tightening the stuffing box cover. If the leak cannot be eliminated by tightening the cover, the gland packing should be replaced. To prevent water leakage during repairs, the pipeline is blocked, often with an elliptical plug
The gland packing can be replaced without shutting off the pipeline. In this case, during repair, a ring made of sheet rubber 12-15 mm thick should be installed on the valve spindle (under the housing cover). To replace the stuffing box, the spindle is lifted up to the stop. In this case, the rubber ring is pressed against the housing cover, thereby sealing the gap between the spindle and the cover, and the flow of water into the gland seal from the pipeline stops. Then the bolts and nuts are unscrewed, the stuffing box cover is lifted and the old packing is removed.
Having cleaned the spindle and the body from the old packing, dirt, rust, a new stuffing box is laid. If the material that was used for sealing is unknown, then it is selected depending on the temperature of the water passing through the valve. At a water temperature of not more than 60 ° C, an stuffing box cotton packing is used: CBN and HBTS; at a higher temperature, asbestos material or a fluoroplastic bundle. The industry produces stuffing box packing in the form of a cord.
The gap between the body and the spindle must be filled with stuffing box packing so that during operation the stuffing box cover can be tightened 2-3 times.
Instead of cotton packing, a split rubber bushing can be used in the gland packing. In this case, when sealing the packing, do not strongly squeeze the sleeve with a cover, as this will increase the friction of the spindle against the sleeve and accelerate its wear. .
Loose shutoff of the water flow in the valves is formed due to damage to the sealing surfaces, wear of the spindle thread.
Damage to the sealing surfaces is determined as follows. Remove the housing cover and take out the spindle with disks. inner surface housings and rings are cleaned of dirt, rust. Paint is applied to the sealing surfaces of the ring and disc, the spindle and discs are re-inserted into the body, after which the valve is closed and opened several times, bringing the rings and discs into contact. Then the disks are taken out again, inspected, revealing scratches, roughness, which stand out on the surface with dark dashes and spots. Defective places on the sealing surfaces with a depth of 0.01-0.3 mm are removed by scraping, with a depth of less than 0.01 mm - by grinding.
Scraping is performed manually or with a mechanized tool in several steps, periodically checking the contact surfaces of the ring and disk. For lapping, see § 6.
A damaged spindle with stripped threads is replaced or repaired by welding metal and turning it to its original dimensions.
Leakage at the points of attachment of fittings to pipelines is eliminated in the same way as leakage in flanged pipeline connections. If water leaks through a damaged cast-iron body or cover (cracks, fistulas, shells), they are replaced.
Cork taps. There may be the following malfunctions in plug valves: water leakage through the stuffing box seal, loose shutoff of the water flow, leakage At the points where the valves are connected to pipelines.
Leakage of water through the stuffing box seal is eliminated by tightening the stuffing box cover. If the leak cannot be eliminated in this way, replace the gland packing.
In order to prevent water from entering the room, the pipeline is blocked with shut-off valves installed on it before and after the repaired tap. In the event that it is impossible to shut off the pipeline, a device is used that hooks onto the pipeline with grippers, then with a handle with a screw that rotates in a nut welded to the bar, and the device presses the plug to the body. wrench, placing one of its sponges under the body, and the other on the top of the cork.
To replace the gland packing, the bolts are unscrewed and the gland cover is lifted, after which the old gland packing is removed, the cork body and spindle are cleaned of the adhering packing. The material for the gland packing is chosen in the same way as for the valve.
Loose shutoff of the flow of water in plug valves is eliminated by grinding.
After grinding, the cork is thoroughly wiped, washed to remove the remnants of the abrasive paste and lubricated with a thick lubricant. Then they send the body and assemble the crane.
Leakage □ of the place is attached^ to trutproyao - yan DM is mined so Ai, LMK leak and ryІbboSHLH ("LINS - KIYAH, PrN of the need to disassemble the pc"іEі&OYSїGO connection OR son to. krinom, g. nilurachivaі from it from the valve body.Then corp>: remove from the rail on the pipeline, if the krill is located close to the wall, then all the protruding parts (stuffing box cover, plug) are first dismantled on the crane, and then the body is unscrewed with an adjustable wrench.
Valves have the same faults as plug faucets. In addition, thread wear on the spindle, foreign particles entering the valve body, and damage to the valve seat are possible.
Leakage through the stuffing box seal is eliminated by tightening the stuffing box nut or replacing the stuffing box packing.
In the event that it is impossible to shut off the pipeline, before replacing the stuffing box, the spindle with the valve is lifted up to the stop by turning the handwheel counterclockwise. In this case, the valve with its upper surface will press against the housing cover and partially block the gap through which water enters. To hermetically close this gap, in order to prevent leakage when replacing the gland packing of the valve, a valve is installed on the spindle above the valve. rubber gasket 3-4 mm thick, i.e., as in a valve (see above).
When lifting the spindle upwards, do not apply great force to the handwheel, as this may cause the valve to come off the spindle.
Leaky flow shutoff in water valves is observed when the sealing gasket or thread on the spindle wears out, the gasket falls out of the valve, foreign objects get between the valve and the seat, or the seat is damaged.
The worn gasket is replaced with a new one made of the same material as the previous one (rubber, leather, heat-resistant rubber, paronite, fiber).
To replace the gasket, the water supply to the pipeline on which the valve is installed is shut off, and the housing cover is unscrewed with an adjustable wrench. Unscrew the nut that secures the gasket, remove the worn gasket. A new gasket is cut out with a punch and installed, securely fastened with a nut. To ensure that the nut does not spontaneously turn away, the thread protruding from the nut is covered with a layer of waterproof paint.
Before assembling the valve, the spindle with the valve is screwed into the body cover and the threads on the cover are coated with graphite grease. In this case, it is necessary to check the gasket under the valve head and, if it is damaged, replace it.
Loose shutoff of the flow in the valves is eliminated by grinding metal sealing surfaces (valves and seats).
The wear of the thread on the spindle does not allow the valve to be pressed tightly against the seat: the handwheel scrolls and the water flow is not blocked. In this case, the flow of water into the pipeline is blocked and the cover is unscrewed from the housing. Then, turning the handwheel clockwise, unscrew the spindle from the cover. If the threads on the spindle are worn or damaged, the spindle is replaced. To do this, remove the handwheel, unscrew (loosen) the stuffing box nut and take out the spindle, remove the valve by removing the retaining ring. The new spindle is installed in the reverse order.
" In the absence of a new spindle, the operation of the water valve can be restored by installing a thicker gasket. Due to the fact that the thicker gasket narrows the flow area of the valve, such repairs can only be carried out on the lower floors of the building, where the pressure in the water supply network is high.
Foreign particles (scale, chips, sand) between the valve AND the seat are first tried to be removed by flushing. To do this, open the water fittings installed after the valve, and open and close the valve several times by rotating the handwheel. If at the same time the tightness is not restored, i.e., when the valve is closed, the water is poured out through the open water fittings, then the housing cover is removed and the extraneous ‘jiCTHía H.'t feed and kligina are removed.
At the parade, neither ssdlp can be cut off, use - nwiVjya frs1u. For jporo n. flEJSpTWJWiur U Body IS1GGILL RMCCTO Kpl. riUK» Milling of the seat surface is carried out by cutting edges while turning the cutter around the axis - If it is not possible to remove the shell by milling*, then replace the body or, having reamed the hole, insert a new seat, machined from bronze or brass on a lathe.
Shr = 7p>r1", k! valves. Repair of return valves (lifting and flogged) is carried out when the reverse flow of water is not tightly blocked and the body and parts are destroyed.
Loose shutoff of the return flow is observed when the sealing surfaces of the valve and seat are destroyed and foreign objects get between them, damage and wear of the axles and hinges of rotary valves.
The destruction of the sealing surfaces of valves and seats and the ingress of foreign objects into them is eliminated in the same way as in valves.
’ Damaged rotary valve stems must be replaced after the valve has been dismantled. When the hinge (earring) is worn out rotary valve refurbishment is carried out by welding a worn hole and then drilling it to the required diameter, or drilling a hole of a larger diameter than the previous one, after which a steel or brass bushing is pressed into it with inside diameter, corresponding to the outer diameter of the axis of the rotary valve.
The destruction of steel cases and parts is eliminated by welding, cast iron - by replacement.
Control armature. When water leaks through the stuffing box seal when the flow is not completely shut off
Control valves (pressure regulator, temperature flow) are repaired in the same way as shut-off valves.
Double adjustment taps installed in rooms where overheating is observed are disassembled and the presence of a reacting glass is checked. If there is no glass, the tap is replaced.
After repair, pipeline fittings are tested for strength and density of the body with a pressure of 1.6 MPa.
General provisions
1. Real job description defines functional responsibilities, rights and responsibility of a repairman.
2. A person with a secondary education and appropriate training in the specialty is appointed to the position of a repairman.
3. The mechanic-repairman must know the structure of the repaired equipment, units and machines; machine regulation rules; ways to eliminate defects in the process of repair, assembly and testing of equipment, units and machines; device, purpose and rules for the use of used control and measuring instruments; design of universal and special devices; methods of marking and processing simple various parts; system of admissions and landings; quality and roughness parameters; properties of acid-resistant and other alloys; the main provisions of preventive maintenance of equipment; design features repaired equipment, units and machines; specifications for repair, assembly, testing and regulation and for the correct installation of equipment, units and machines; technological process repair, assembly and installation of equipment; rules for testing equipment for static and dynamic balancing of machines; geometric constructions with complex markup; methods for determining premature wear of parts; ways to restore and harden worn parts and apply a protective coating.
4. A repairman is appointed to the position and dismissed by order of the head of the institution in accordance with the current legislation of the Russian Federation.
5. The mechanic-repairman reports directly to the deputy head of the ACS, or the deputy head of engineering, or the deputy head of construction, or the head of the economic department, or the head of the technical department, or the head of the construction department.
Job Responsibilities
Implementation of repair work. Disassembly, repair, assembly and testing of components and mechanisms. Repair, installation, dismantling, testing, regulation, adjustment of equipment, units and machines and delivery after repair. Locksmith processing of parts and assemblies. Manufacture of complex devices for repair and installation. Preparation of defective repair reports. Performing rigging work using lifting and transport mechanisms and special devices. Identification and elimination of defects during the operation of the equipment and when checking during the repair process. Accuracy and load testing of repaired equipment.
Rights
The repairman has the right to:
1. make proposals to the management of the institution on the organization and conditions of its labor activity;
2. use information materials and legal documents necessary for the performance of their official duties;
Educational practice PM №1
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4. improve your skills.
A repairman enjoys all labor rights in accordance with Labor Code RF.
Responsibility
The Maintenance Technician is responsible for:
1. timely and high-quality implementation of the duties assigned to him;
2. organization of their work, timely and qualified execution of orders, instructions and instructions of the management, regulatory legal acts on their activities;
3. compliance with the rules internal regulations, fire safety and safety precautions;
4. maintaining the documentation provided for by the current regulatory legal acts;
5. prompt action, including timely informing the management, to eliminate violations of safety, fire and other rules that pose a threat to the activities of the institution, its employees and other persons.
For violation labor discipline, legislative and regulatory legal acts, a repairman can be brought in accordance with applicable law, depending on the severity of the misconduct, to disciplinary, material, administrative and criminal liability.
Valve maintenance
Periodicity and volumes Maintenance and repair of shut-off valves are determined by the manufacturer's instructions and the schedule approved by the chief engineer of the operating organization.
On the ground (in order to speed up the process), the repair of shut-off valves is partially limited to grinding small valves or taps, which consists in the fact that the spool or plug is rubbed with a fine
emery with machine oil to the nest. In this case, the stem seals and plugs are also stuffed. Grooving of spools, cheeks, rods, ground-boxes is done in workshops on lathes or lapping machines. The detected defects are eliminated in the same ways as during the repair of shutoff valves.
To speed up the operations of turning on and off pipelines and to facilitate the repair of shutoff valves, wells with walls made of rubble or reinforced concrete prefabricated elements are constructed on all tie-ins and on all burst gates. They are equipped with durable covers and well-marked signs.
In the working condition of the stop valves, the passage of the medium through the stuffing box and gasket seals is not allowed.
The technical condition of the valve during operation must be determined by diagnostic control. For determining technical condition body and welded seams of the gate valve, acoustic emission (AE), ultrasonic (US) and other non-destructive testing methods are used.
The diagnostic control of the gate valve is combined in time with a major overhaul and is also carried out when excessive stresses are detected on the nozzles or when failures occur in the operation of the gate valve according to the criteria limit states. When diagnosing, devices and AE sensors and ultrasonic testing devices or flaw detectors are used.
Diagnostic control and a conclusion based on its results are carried out by specialized organizations that have the permission of the Gosgortekhnadzor of Russia, or specialists from RNU, TsBPO in the presence of a developed and approved method of diagnostic control.
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Checking the tightness of the valve gate during operation can be carried out by acoustic emission leak detectors.
At existing main oil pipelines, fittings are also tested for strength and density of materials and welds, tightness in relation to external environment, seal tightness and performance. The testing of fittings is combined in time with the testing of oil pipelines or is carried out after completion overhaul oil pipelines.
The test mode and test pressures are established depending on the period and parameters of operation of oil pipelines in accordance with the regulatory documents governing testing on existing oil pipelines.
Locking and control devices. Shut-off valves- type of pipeline fittings designed to block the flow of the medium. It has the widest application and usually makes up about 80% of the total number of products used. Shut-off valves include both test-bleed and control-bleed valves used to check the level of a liquid medium in tanks, take samples, bleed air from upper cavities, drain, etc. Fig. 5, a, c) and valves (Fig. 5, b). The control valve differs from the shut-off valve only in the design of the valve (spool). The valve has a tail device that allows you to smoothly change the flow area of the valve. In addition, fine threads are cut into the control valve spindle.
Rice. 5. Shutoff valves:
a - through passage valve (shut-off): 1
- cap-handwheel; 2 -
spindle head; 3 - spindle; 4
- stuffing box; 5
- lid; 6
- spool; 7 - body; b - brine valve: 1
- frame; 2 - cheeks; 3 - wedge; 4 -
stock; 5 - stuffing box; 6
- flywheel; in - two-way shut-off freon valve: 1
- frame; 2 - spindle; 3 - stuffing; 4 -
screw; 5 - gasket, 6
- cap; 7 - branch pipe; 8 -
tee; 9 -
cap nut.
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Shut-off and control valves are installed so that the direction of movement of the refrigerant coincides with the direction of valve lift (under the valve). A shut-off valve is usually installed before each control valve, since the control valve cannot be used as a shut-off valve.
On fig. 5, in a two-way freon angle valve with a small flow section is shown. A two-way valve allows you to turn off one of the passages in working condition or connect both passages at the same time. Freon compressors often use a valve of this design.
Similar information.
Cranes- this is a valve designed to quickly turn on or off a pipeline, apparatus or device, as well as to regulate the flow of gas through a gas pipeline. According to the method of sealing, valves are divided into tension and stuffing box. The main elements of the valves are the body and the conical plug with a hole for the passage of gas. On a turnkey tetrahedral head, a risk is applied that coincides with the direction of the hole in the plug. If the risk on the head coincides with the direction of the pipeline, then the gas passage is open, and if the risk is directed across the pipeline, then the passage is closed. In tension valves, at the bottom of the plug there is a threaded stud, on which a washer is put on and a nut is screwed on. The tightness in these valves is provided by the tension of the nut. Cranes installed on gas pipelines must have stops that limit the rotation of the plug within 90 °. The tightness in stuffing box valves is provided by stuffing box packing.
Ball Valves. The shut-off element of the valve is a polished stainless steel ball with a through hole for gas. The ball valve has a high gas density, has a long service life, does not require maintenance, tightening or lubrication of rubbing surfaces.
Gate valves are the most common shut-off devices used on gas pipelines with a diameter of more than 50 mm. The gas is turned off by a movable shutter in the form of a disk or wedge. The movement of the shutter in the valve body is carried out by rotating the handwheel connected to the shutter by means of a spindle having a tape thread on its surface.
According to the location of the threaded part of the spindle, there are gate valves with a sliding and fixed spindle. According to the device of gate valves, they are divided into wedge and parallel. Wedge gate valves can be with a solid (wedge) and hinged (consisting of two disks) gate. For parallel valves, the valve consists of two halves or disks, between which there is a spacer.
Shut-off valve consists of a body with a lid and a plate. A threaded spindle passes through the cover, at one end of which a plate is fixed, and at the other - a flywheel. The space between the housing cover and the spindle is filled with a gland seal.
Valves on pipelines are installed in such a way that the direction of movement of the medium coincides with the arrow on the body. In this case, the movement of the flow is carried out under the valve. positive qualities valves are the possibility of smooth regulation and satisfactory closing tightness. Their essential shortcoming is the big aerodynamic resistance created by it at passage of a stream.
Requirements for shut-off and control valves: tightness of gates; ease of movement; low aerodynamic resistance; on the flywheels of gate valves and gates, the direction of rotation when opening and closing must be indicated, on the fittings - the trademark of the manufacturer, the diameter of the conditional passage, the working pressure of the medium, the direction of flow (for valves).
Maintenance of shut-off and control valves consists in checking gas leaks into the room through coupling and flange connections, stuffing box seals, as well as gas leaks into furnaces and gas ducts due to leaky valves.
Monitoring the detection of gas leaks, leakage of gas fittings is carried out by operators of gas boiler houses, and the elimination of identified malfunctions is carried out by employees of the gas service. When establishing a gas leak through flange connections, it is necessary to tighten the bolts of the connection or replace the gaskets, which are made of paronite, low-petrol rubber, asbestos cardboard, etc.
In case of leakage of the stuffing box connection, it is necessary to tighten the stuffing box cover (nut) or replace it. Oil seals are made from asbestos strands lubricated with grease.
With leakage threaded connections connections are tightened or sealing hemp or jute strands impregnated with oil paint are replaced.
To ensure ease of movement and tightness of valves, their timely lubrication is necessary. The sealing surfaces of the body and the plug are coated with grease during assembly. At operating temperatures up to 25 ° C, technical vaseline or grease is used, and at temperatures above 25 ° C, a heat-resistant lubricant based on mountain wax, cylinder oil and graphite powder is used.
To ensure the necessary gas tightness, the shut-off surfaces of the taps are rubbed with various lapping powders and pastes based on emery, corundum, carborundum, finely crushed glass, etc. After lapping, the gas tightness is checked by lowering the tap into water and passing air under pressure through it.
The tightness of the sealing surfaces of the gates to the sealing surfaces of the body is ensured by their appropriate lapping and scraping treatment.
Before installing valves on gas pipelines, they must be tested for density using a kerosene test: on a closed valve, one side of the valve is painted with a chalk solution and allowed to dry; then the valve is placed with the painted side down, and on the other side, kerosene is poured onto the valve. If after 1 hour no kerosene stains are found on the painted side of the disc, the density of the valve is assessed as sufficient.
Purge and safety plugs
Purge candles are used to remove the gas-air mixture from gas pipelines into the atmosphere when gas is released into the gas pipeline or when the operation of gas networks is stopped.
Are established on the most remote from input sites of the general boiler gas pipeline.
The diameter must be at least 20 mm. It is displayed on the roof at least 1 m from the eaves and must be protected from precipitation.
After the disconnecting device, a fitting with a valve for gas sampling is installed.
Safety candles serve for additional protection of a fire chamber from a gas contamination. Are established on the gas pipeline before a torch between working and control locking devices. The requirements for the device are similar to the requirements for blowing candles. It is forbidden to combine spark plugs in the same manifold with purge plugs and do not use spark plugs for purging.
A fitting with a plug for a pressure gauge is placed in front of the locking device on the safety candle to determine the density of the working and control locking devices.
The shut-off valves on the blow-out candle and safety candles must be permanently open after the unit has been switched off.
Safety explosion valves
They serve to protect the furnace and chimneys from destruction in case of a possible explosion.
The number, area and installation location of explosive valves is determined by the project.
Are established in the top part of a fire chamber and a flue, in places of possible accumulation of gas. The area of one valve must be at least 0.05 m 2 (500 cm 2).
If it is impossible to install explosive valves in places safe for service personnel, they must be provided with smoke-exhausting protective devices.
Valve design:
1. Folding (discharge) - consist of metal plate or a metal cover installed on the chimney site. The edges are sealed with clay or sand.
The lid is attached to the platform with a loop or chain.
2. Bursting:
a) metal - a metal membrane with a notch that breaks when pressure increases in the boiler furnace or chimney;
b) asbestos - a sheet of asbestos laid on a metal frame with a grate. The edges of the asbestos are sealed with a metal strip. The thickness of the asbestos should not exceed Zmm, with a greater thickness, cuts are made on the sheet.
On time, set by the instruction personnel must check the condition of the explosive valves.
All domestic and imported valves newly installed at the facilities of the main oil pipeline must have certificates of conformity certifying the compliance of the shut-off valves with the requirements of State standards and normative documents Russia and the permission of the Gosgortekhnadzor of Russia for the right to manufacture and use these products.
RNU (JSC) should take into account the service life, operating time and the number of “closed - open” operation cycles of the valve.
The fitting is considered to be operational if:
The strength of the materials of parts and welds operating under pressure is ensured;
There is no leakage of the medium and sweating through the metal and welds;
The tightness of stuffing box seals and flanged fittings in relation to the external environment is ensured;
The tightness of the valve gate is ensured in accordance with the passport for the shut-off valves;
Provides smooth movement of all moving parts of the valve without jerking and jamming;
The electric drive ensures smooth movement of the shutter, opening and closing within the time specified in the passport; the electric drive is switched off when the shutter reaches the extreme positions and when the torque exceeds the permissible value on the yoke assembly.
If any of these conditions is not met, the valve is considered inoperable and is taken out of service.
Reinforcement performance is characterized by reliability indicators. Reliability indicators include: the assigned valve service life, the assigned resource - in open-closed cycles, the assigned service life before repair, the probability of failure-free operation during the assigned resource.
Valve inoperability is determined by the criteria of failures and limit states.
The failure criteria for stop valves are:
Loss of tightness in relation to the external environment that cannot be eliminated by an additional tightening;
the passage of the medium in the shutter in excess of the allowable;
impossibility of working movements of the locking body (jamming of moving parts) when opening and closing the valve;
increase in response time in excess of the allowable;
failure of the electric drive.
The criteria for limit states of reinforcement are:
Achievement of the assigned service life;
destruction or loss of density of the base material and welds;
Violation of the geometric dimensions of the mating parts (due to wear or corrosion damage).
Upon reaching the designated service life, the shut-off valves are subject to re-examination in order to determine their technical condition and the possibility of extending their service life.
Reliability indicators, failure criteria and limit states are indicated in the valve certificates.
Control of operability and technical condition of valves is carried out by external inspection, diagnostics and testing
During an external examination, the following are checked:
condition and density of materials and welded joints of reinforcement;
smoothness of movement of all moving parts of valves and electric drives;
the serviceability of the electric drive;
tightness of fittings in relation to the external environment, including:
tightness of gasket seals;
tightness of stuffing box seal.
In the working condition of the stop valves, the passage of the medium through the stuffing box and gasket seals is not allowed.
The technical condition of the valve during operation must be determined by diagnostic control. Acoustic emission (AE), ultrasonic (US) and other non-destructive testing methods are used to determine the technical condition of the valve body and welds.
The diagnostic control of the gate valve is combined in time with a major overhaul, and is also carried out when excessive stresses are detected on the nozzles or when failures occur in the operation of the gate valve according to the criteria for limit states. When diagnosing, devices and AE sensors and ultrasonic testing devices or flaw detectors are used.
Diagnostic control and a conclusion based on its results are carried out by specialized organizations that have the permission of the Gosgortekhnadzor of Russia, or specialists from RNU, TsBPO in the presence of a developed and approved method of diagnostic control.
The results of diagnostic control (conclusion) are entered in the valve form or attached to its passport.
Checking the tightness of the valve gate during operation can be carried out by acoustic emission leak detectors.
On operating main oil pipelines, valves are also tested for strength and density of materials and welds, tightness in relation to the external environment, tightness of the gate and operability. The testing of fittings is combined in time with the testing of oil pipelines or is carried out after the overhaul of oil pipelines.
The test mode and test pressures are established depending on the period and parameters of operation of oil pipelines in accordance with the regulatory documents governing testing on existing oil pipelines.
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TYPICAL INSTRUCTION ON LABOR SAFETY
when servicing and repairing valves
TOI R-39-017-96
Developer: company "Gazobezopasnost" JSC "Gazprom"
Coming into effect
Validity
1.GENERAL SAFETY REQUIREMENTS
1.1. Persons who have reached the age of 18 and who have undergone special training are allowed to maintain and repair gas shut-off valves. safe methods maintenance and repair work and medical examination of the state of health.
1.2. Personnel performing maintenance and repair of shut-off valves must undergo an occupational safety knowledge test at least once every 12 months.
1.3. Repair work on shut-off valves installed on the linear part of existing gas pipelines, on technological gas pipelines of the CS, GDS, AGNKS, SPHG are gas hazardous works. These works must be carried out with a special permit.
1.4. Personnel performing maintenance and repair of shut-off valves from the group of physical hazardous and harmful production factors may be affected by:
- explosion and fire hazard;
— moving machines and mechanisms;
- moving parts production equipment;
- moving products;
- collapsing structures;
- increased air pollution working area;
- increased or decreased temperature of equipment surfaces;
- increased or decreased air temperature of the working area;
— elevated level noise in the workplace;
- increased vibration level;
- increased voltage in the electrical circuit, the closure of which can pass through the human body;
- sharp edges, burrs and roughness on the surfaces of tools and equipment.
1.5. During repair work, it is necessary to install the fittings provided for by the project. It is forbidden to use shut-off valves that do not have technical passports, confirming its compliance with this series, as well as the trademark on the valve body.
1.6. Shut-off valves on main gas pipelines, on gas pipeline branches, on SPGS wells, as well as separately standing at industrial sites, must have a fence with two exits, made in accordance with the project.
1.7. Shut-off valves (faucets, valves, check valves, valves, etc.) must be designed for maximum pressure and limiting temperatures of the medium in the gas pipeline.
It is forbidden to use shut-off valves for operating parameters that do not correspond to those specified in the technical documentation.
1.8. Works on maintenance and repair of shut-off valves installed in the wells of gas pipelines are carried out according to the permit.
1.9. It is not allowed to work in gas pipeline wells in shoes lined with steel nails.
1.10. Work in wells and in a gassed area should be carried out by personnel in hose gas masks with safety belts on. It is forbidden to go down into the wells without protective equipment.
1.11. Work in the wells must be carried out by a team of at least 3 people.
2.SAFETY REQUIREMENTS BEFORE STARTING WORK
2.1. Before starting work, the staff must:
- put on proper work clothes, get the necessary funds personal protection, fixtures and tools;
- prepare workplace(platform), remove foreign objects, provide lighting if necessary, arrange tools and devices in the right order;
- check the serviceability of hand and mechanized tools. Hammers used during work must be mounted on handles having an oval section and wedged, wrenches - correspond to the sizes of bolts and nuts, hammers, mandrels, core crimps - do not have worn strikers and burrs.
- when checking a power tool - make sure that it is grounded, the wire insulation is not damaged, the connection terminals are closed;
- when inspecting lifting devices, check their compliance with the requirements safe operation;
- remove the hoses to the pneumatic cylinders on all pneumatic drives of the cranes being repaired, the handwheels for manual control of the cranes, the impulse gas supply pipes on the pneumatically driven cranes, the operational voltage from the limit switches of the cranes, hang posters "Do not open", "Do not close" on manual oil pumps, "Do not turn on ”, “People are working” on the shield remote control, posters indicating the position of the valve shutter ("Open", "Closed") on each valve.
- remove power from the automation panel of the shut-off valves to be serviced or repaired.
2.2. Before carrying out work in wells, they must be thoroughly ventilated (ventilated).
3. SAFETY REQUIREMENTS FOR THE MAINTENANCE OF SHUT-OFF VALVES
3.1. Shut-off valves must have:
- numbering according to the technological scheme,
- indicators of the direction of rotation of the steering wheel (opening and closing),
- position indicators (open, closed) for cranes,
- indicators of the direction of gas movement.
3.2. The valves located on the process gas pipelines of the GPA piping and the general station valves must have the same type of numbering.
3.3. Shut-off valves on pipelines and devices (with the exception of bypass devices) should be opened only after equalizing the gas pressure in adjacent sections of the pipeline or in the presence of a certain pressure drop that does not exceed that specified by the manufacturer.
3.4. The main type of ball valve control is pneumohydraulic or pneumatic actuators using the pressure of the transported gas.
3.5. The normal position of the linear valve is open; the normal position of the bypass valve is closed. The position of the valves on the jumpers between the threads of a multi-line gas pipeline depends on the mode of operation of the gas transmission systems.
3.6. Valves with soft ball seals must not be used as gas flow regulators.
3.7. In taps, in order to create tightness in the closed position, as well as to facilitate the rotation of the gate, it is necessary to periodically stuff the tap grease.
3.8. The tightness of the joints of gas pipelines and fittings located in rooms, wells and on open industrial sites must be controlled in accordance with the established regulations.
A soap solution should be used to check the tightness of the joints. It is forbidden to search for gas leaks using fire.
3.9. It is forbidden to tighten the bolts and studs of the flanged connections of shut-off valves under pressure.
3.10. It is forbidden to bleed gas through the gap of the divorced flanges of valves, gate valves. Bleed gas from the gas pipeline section to be repaired only through purge candles.
3.11. It is forbidden to use flashlights and open flames to illuminate and warm the frozen parts of the valves.
For illumination, it is necessary to use a serviceable rechargeable flashlight in explosion-proof design. To thaw frozen equipment, use only hot water and steam.
3.12. The rods and worm gears of shut-off valves must be lubricated with grease or grease.
3.13. When stuffing the valve with grease, the employee must:
- when unscrewing the plug that closes the lubrication channel, stand on the side and hold the plug so that when it is ejected by pressure, the plug does not hit your hand.
- with the end of stuffing, turn the syringe carefully, do not stand against the lubrication channel.
3.14. Maintenance of the geared part of a pneumatically actuated valve with connected power gas hoses is prohibited.
Before working near the pneumatic actuator, the power gas hoses must be disconnected from the pneumatic actuator.
3.15. When servicing the shut-off valves included in the electric automation circuit, the power supply from the automation panel must be removed.
4. SAFETY REQUIREMENTS FOR REPAIR OF SHUT-OFF VALVES
4.1. Repair work on valves is divided into scheduled and emergency.
Planned work is carried out according to the schedule. Emergency operations are carried out immediately.
4.2. When performing repair work, it is prohibited:
- dismantle shut-off valves under pressure.
- carry out work on the repair of the control unit, filter in the presence of medium pressure in the valve control system.
4.3. When working on the repair of shut-off valves, only serviceable tools and equipment should be used.
4.4. Do not stop the rotating tool with your hands or other objects.
4.5. When pressing in, the parts must be placed without distortions, and the hydraulic clamps must be held only by the handles.
4.6. When disassembling shut-off valves, the removed assembly units and parts must be placed on previously prepared places (not on the aisles), large and heavy units - on the floor on wooden stands, positioning them so that they do not tip over.
4.7. Do not remove and install manually assembled hydraulic cylinders and other components that have significant overall dimensions and weight.
4.8. When cutting metal, it is necessary to use a safety shield and goggles.
4.9. When repairing the underground part of the locking devices, trenches are made. When working in a trench at a depth of more than 1 m - slopes.
4.10. For descent into the trench and ascent from it, portable ladders are used, of which there must be at least 2 and they must be installed in opposite directions.
4.11. When working in a trench, at least 2 observers should be on the ground, ready to provide immediate assistance to workers in the trench. All workers in the trench must have life belts with ropes tied to them.
4.12. When repairing control units and drives of cranes installed at a height of more than 0.75 m, it is necessary to use ladders and stepladders.
4.13. For the safe performance of work on the repair of valves, it is necessary to timely check the correctness of the readings of the pressure gauges installed in the piping of the locking device, comparing them with the readings of the control pressure gauges.
4.14. It is forbidden to use pressure gauges with an expired calibration period and with visible damage.
5. SAFETY REQUIREMENTS IN EMERGENCIES
5.1. Upon detection of an emergency situation or the threat of its occurrence, the employee must:
- ensure their own safety with the use of protective equipment;
- notify the personnel located in the danger zone and the manager (responsible executor) of the work;
— to take part in priority measures to eliminate the accident in accordance with the PLA.
Workers who do not have personal duties in accordance with the PLA must immediately leave the danger zone.
5.2. In the event of an emergency, the work manager must:
— notify personnel about the accident;
- to provide priority measures for the rescue and evacuation of people, the provision of first aid to the victims, as well as measures to localize and eliminate the accident in accordance with the operational part of the PLA.
6. SAFETY MEASURES AFTER REPAIR WORK IS COMPLETED
6.1. Upon completion of work, the personnel must:
- turn off all the mechanisms used in the repair;
- check if the tool is left at the workplace;
- tidy up the workplace, clean the equipment from contamination;
- collect waste liquids, used cleaning material, other waste in a special container and hand them over for disposal in the prescribed manner;
- hand over the workplace, fixtures, tools and protective equipment to the work manager;
- clean and put in the designated place overalls;
- take the necessary personal hygiene measures (thoroughly wash your hands, take a shower, etc.).
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