The invention is intended for repairing shut-off pipeline valves. A method for repairing gate valves, mainly wedge valves, by installing, with a gap, finally processed seats in the body bores onto a self-curing adhesive composition, followed by assembly and curing of the assembled adhesive composition. Before assembly, threads are cut in the body bores and on the seats. Each seat is made with an annular radial protrusion. After this, the seats are screwed onto the adhesive self-curing composition into the threaded bores of the body. In this case, an elastically deformable element is installed between the annular radial projections of the seats or the ends of the seats and the body. This allows the screw-in seat to self-align along the wedge, and one elastically deformable element ensures that all gaps are removed, which increases the tightness of the connection between the seats and the body. This implementation reduces labor intensity and increases the reliability of valve repair. 3 ill.

The invention relates to the mechanical engineering industry, in particular to the repair of pipeline fittings. There is a known method of restoring the sealing fields of the valve, which consists in surfacing a hard stainless alloy directly onto the body and wedge of the valve, followed by machining and lapping (see A.F. Pongilsky. Mechanic for repairing pipelines and steam-water fittings. M.: Higher School, 1973). This method is quite labor-intensive and requires special, precise and complex equipment. There is also a known method for repairing wedge valves (see AS 310078), which consists of installing, for example, final processed metal rings on a self-hardening composition in the gap in the bored grooves of the body and wedge, followed by assembling the wedge and body, holding the assembly until the composition is cured . The disadvantages of this method include the possibility of incomplete contact of the sealing rings of the housing and the wedge with each other (and therefore lack of tightness) and the impossibility of self-installation in the absence of a lateral gap between the ring and the groove. And if these gaps are made sufficient for self-installation of the rings, it is possible that the self-hardening composition is squeezed out before the start of its polymerization, which means there is no elastic compression of the rings to each other, which also leads to loss of tightness or the appearance of incomplete contact of the rings with the adhesive composition, which reduces the reliability of the connection. Moreover, this method is not applicable to valves with screw-in seats (see D.F. Gurevich. Calculation and design of pipeline fittings. Leningrad: Mashinostroenie, 1969, Fig. 129-131). The objective of the invention is to reduce labor intensity and increase the reliability of repairs. The technical result is achieved by the fact that the sealing fields of the wedge and screw-in seats are mechanically processed “as clean”, i.e. with the removal of the minimum allowance until signs of wear disappear, grind in the sealing fields of both the body seats and the wedge, cut threads on the seats in the body bores, then screw onto an adhesive self-hardening composition into the threaded bores of the body, between the annular radial protrusions of the seats or an elastically deformable element is installed at the ends of the seats and the body. The essence of the invention is illustrated by drawings: Fig. 1 shows a cross-section of a wedge valve with screw-in seats; Fig. 2 - view A in Fig. 1, option, in Fig. 3 - view A in Fig. 1, option. In the body 1, 2 seats 3 are installed on the thread 2 with a gap 4, in which a self-hardening composition 5 is placed, limited by an elastically deformable element 6 or 7 installed between the body 1 and the annular radial protrusion 8 or the end 9 of the screw seat 3, the sealing field 10 of which interacts with the sealing field 11 wedge 12. After disassembling, the seats 3 are cleaned of dirt, the sealing fields are processed “as clean” and ground in, the seat threads and body bores are cut or the existing threads are loosened with a gap sufficient for self-installation, then the sealing fields 11 of the wedge 12 are also processed “as clean” and ground in their. Then the threads of the seat 3 are covered with a self-hardening composition 5, elastically deformable elements 6 or 7 are installed and the seat 3 is screwed into the body 1, after which the wedge 12 is inserted into the body 1, taking into account the overlap of the sealing fields of the wedge and the seat, ensuring the tightness of the product, and is left assembled until self-denial. The valve is ready for operation. Depending on the degree of wear of the sealing fields of the seats 10 and the wedge 11, one or two seats are installed on the elastic element 6. Thus, minimal machining “as clean”, grinding in four fields, cutting threads - this is the volume of machining of the proposed method, which is significantly less than known analogues. Gaps in the mating allow the screw seat to self-align along the wedge, and one elastically deformable element allows you to select all the gaps in the seals.

Claim

A method for repairing gate valves, predominantly wedge valves, by installing, with a gap, finally processed seats in the body bores on an adhesive self-curing composition, followed by assembly and curing of the adhesive composition assembly, characterized in that before assembly, threads are cut in the body bores and on the seats, with each seat being made with an annular radial protrusion, after which the seats are screwed onto an adhesive self-hardening composition into the threaded bores of the body, while an elastically deformable element is installed between the annular radial protrusions of the seats or the ends of the seats and the body.

Similar patents:

This invention relates to a shut-off valve comprising a housing (1), two o-ring seals (20) located in this body (1), and two gate discs (12) located between these o-ring seals (20), which, with the help of an actuator (7), ) can be brought into contact with both O-rings (20). According to the invention, it is proposed that each gate disk (12) on its side facing the other gate disk (12) be equipped with a recess (28), in which there is a corresponding pressure block (22a, 22b), and each pressure block (22a, 22b) on its facing on the other side of the pressure block there is a recess (34, 37), while both recesses (34, 37) together form a space (40) in which a package (23) of disc springs is placed, containing several disc springs (41) with a first elastic force and a first stroke of each spring and a plurality of disc springs (42) with a second spring force and a second stroke of each spring, the first spring force being greater than the second spring force and the first spring stroke being less than the second spring stroke. 6 salary f-ly, 4 ill.

The invention relates to the field of mechanical engineering, in particular to a device for a parallel pipeline valve with a sliding spindle, and can be used as equipment for pipelines for various purposes. The valve consists of a body 1 with cheeks 2, a retractable spindle 3, a wedge spacer element 4 attached to it, gate discs 5, a cover 6 with a stuffing box assembly 7. The body 1 has upper stops 8, and the rear beveled surfaces of the gate discs 5 have shaped (in our case, T-shaped) slots. On the side surfaces of the wedge spacer element 4 there are responsive projections to the T-shaped groove. In the lower inner surface of the body 1 there are lower stops 9 to limit the vertical downward movement of the breech disks 5. To create additional force for lifting the wedge spacer element 4 and to prevent premature lifting of the breech disks 5, springs 10 with pushers 11 are placed in the wedge spacer element 4, and on the rear On the surfaces of the valve discs 5, stops 12 are attached for the pushers 11. The invention is aimed at increasing operational reliability due to reduced wear of the seals while simultaneously simplifying the design and increasing its manufacturability. 1 salary f-ly, 3 ill.

The invention relates to the engineering industry, in particular to the repair of pipeline fittings

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Features of a wedge valve

A valve is a pipeline fitting. The classification of valves is quite diverse. But we will talk about the wedge one. Its design is intended to block the flow of the working medium in the pipeline. A wedge valve has a gate, which, when performing actions aimed at opening or closing it, is located perpendicular to the flow of the working medium.

Its feature is the direct locking element, which has the shape of a wedge. The locking parts of the valve are tapered towards the end and cover the valve seats, which are located at an angle relative to each other.

The functions of wedge valves are as follows. This is a category of shut-off valves designed to completely shut off the flow of the working medium. The wedge valve has only two main positions: open and closed.

How does a wedge valve work?

The valve has a special seat (hole), through which the working medium can move. The gate in the wedge gate valve design is a movable element. It can go up and down.

If the bolt is raised up, the seats (holes) on both sides are in the “open” position. This position allows the working medium to flow freely through the valve and further through the fittings into the general system. If the wedge is in the lowered position, the holes of the seats overlap, which means that the movement of the working medium stops.

How is the wedge gate lifted?

It rises as a result of being screwed onto the spindle. This is a threaded part of the valve; the valve is attached to it with a nut. At the moment when the spindle performs rotational or rotational-translational movements, the wedge rises with it. In turn, the spindle rotates due to the movement of the handle (if it is manual control) or an electric drive.

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Classification of wedge valves

The classification of wedge valves implies their division into narrowed and full bore.

Full bore ones have a diametrical hole size of the rings (sealing rings) equal to the diameter of the pipeline hole. If we are talking about a narrowed version, then the diameter is smaller than the hole in the pipeline system.

Another classification is possible in accordance with the nature of the spindle (rod) movement. In this case, wedge valves can be with a retractable or non-retractable spindle. If the stem is retractable, then when the valve is opened, its height (construction height) increases, while the spindle itself performs a screw-type movement. The non-retractable spindle allows the valve not to change its construction height. The movements of the rod in this case are rotational in nature.

As for the design of the shutters, they can also be different. For example, a conventional wedge valve may have either a rigid gate, or an elastic gate, or a double-disc gate. And now in more detail.

A rigid wedge is a solid piece. Its design allows for a fairly tight fit to the holes of the saddles. But in this case, it is difficult to fit it to the saddles and there is a possibility of jamming. This, of course, is a disadvantage of this type of wedge.

The second version of the wedge in the valve is a double-disc one. This is a design of fixed disks located at an angle. This arrangement forms a wedge.

But the elastic wedge basically also consists of two disks, but its difference is expressed in the movable connection. This is the most airtight version of the valve, since its use ensures a very tight fit of the wedge valve to the holes of the seats. And one more advantage of this type: such valves break much less often than others.

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Advantageous characteristics of a wedge gate valve

The first thing I would like to note as a significant advantage is the simple design of the wedge gate valve (WVG). But that is not all. The hydraulic resistance of this type of valve is quite weak, and, of course, one cannot help but mention the small construction height.

Now about the cons. Here we can safely point out the need to use a lot of force in order to completely open or close the working body. Well, the construction height, when compared with the valves, is much greater.

The reliability of wedge valves during operation directly depends on the correct selection of design and compliance with the required characteristics.

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How to repair a wedge valve correctly?

The fact that wedge valves require regular maintenance, of course, adds a number of inconveniences to the operation process. But the fact that repair of a wedge valve is possible speaks of its advantages over other types. Repair technology varies depending on the current situation. Let's look at a few of the most common faults that can be repaired.

It happens that when using a wedge valve, we pay attention to the insufficient tightness of shutting off the flow of the working medium. What could contribute to this?

This problem can occur as a result of possible defects in the surfaces of the body and shutter. This could be various deposits or damage, such as scale or scratches. What to do in this situation, what repairs to carry out?

To achieve good tightness, it is necessary to grind in the sealing surfaces.

This applies to the bolt and body. Most often their surfaces are made of bronze. First you need to dismantle the valve cover, pull out the valve (body) and grind it. You can use a variety of diamond pastes. The grain size should have a gradual transition from coarser to finer.

Another type of problem occurs when liquid flows through the rod from under the seal. Here, most likely, the rod is not sealed enough. The repair will consist of the following. To correct the situation, you need to tighten the seals, and if necessary, completely replace their packing. If, after replacing the oil seal, the leak still remains, then the problem may be in the rod. This means that shells of a corrosive nature could form in it. If this is the case, then it is unlikely that it will be possible to avoid replacing it.

Inability to turn the flywheel. Everything here is quite simple: the shutter is jammed. This situation occurs in those valves that are not regularly serviced and whose opening is most likely done no more than once a year.

As a result of such operation, scale deposits form on the sealing surfaces.

The technology for such repairs is as follows.

To eliminate this problem, the top cover of the valve is removed and the sealing elements are cleaned. If necessary, the contact surfaces are ground in. Do not knock on the spindle (rod) under any circumstances, as such actions will most likely lead to the guide nut being torn off.

Another common problem: the flywheel can rotate, but the valve does not open. This indicates a broken shutter. Rising stem valves are subject to this fault.

This means that the “cam” of the rod, which is supposed to hold the bolt, has worn out, or the thread on the nut that guides the rod has broken off. The repair will include the following: With the latter option, the worn out “cam” is replaced. Another repair option is to weld it. The nut must also be replaced, if, of course, the design of the valve allows this to be done.

If your valve has a non-retractable spindle, then the valve will fall out when the nut holding it in place is removed. To fix this problem, you need to replace the shutter.

Do not forget that all actions to disassemble the valve if it is under pressure are strictly prohibited.

After installation is completed, air is removed from the valve. To do this, you need to loosen the bolts that press the oil seal. After drops of water appear under the oil seal, you can press the bolts.

1. General Provisions

1.1 Maintenance of shut-off valves is carried out at least once a year. 1.2 Maintenance of shut-off valves is carried out by teams of workers of at least three people when working on an underground gas pipeline and at least two people on an above-ground gas pipeline under the guidance of a specialist.

2 Work procedure

2.1 When maintaining shut-off valves installed on above-ground and underground gas pipelines, the following types of work are performed: - cleaning from dirt and rust; - external inspection to identify distortions, cavities, cracks, corrosion and other defects; - checking the tightness of welded, threaded, flange connections and gland seals using special devices (gas indicators or gas analyzers); - eliminating leaks in flange connections by tightening bolts or changing gaskets; - cleaning the flanges before installing new gaskets; - eliminating gas leaks in the seals by tightening the seal or changing the packing; - acceleration of the worm at the valves and, if necessary, lubrication (avoiding complete blocking of the gas pipeline); - checking the functionality of the valve drive device; - painting of shut-off valves. 2.2 When performing maintenance of fittings installed in a well, the following types of work are additionally performed: - checking the condition of gas well covers and wells for gas contamination; - pumping water from wells (if necessary); - checking the presence and serviceability of shunt electrical jumpers, the condition of sealing of gas pipeline casings, structures of wells, brackets, ladders. 2.3 Before carrying out maintenance work on shut-off valves on underground gas pipelines, the ECP must be turned off. 2.4 Maintenance work on shut-off valves installed above ground is carried out in the following order: - maintenance work on shut-off valves is carried out in accordance with 20.2.1; - the tightness of connections is checked using a foaming solution or an instrument method. 2.5 Maintenance work on the fittings in the well is carried out in the following order: - the well cover is cleaned from dirt, snow, ice; - the condition of the cover in the wells is checked; - the well is checked for gas contamination with special devices through a hole in the lid of the gas well; - the well cover is lifted with a hook; - the well is ventilated for 15 minutes and re-checked for gas contamination; - if necessary, water is pumped out from the well; - in the absence of gas contamination, one of the workers in a rescue belt descends into the well; the team workers located on the surface of the earth must hold the ends of the ropes from the rescue belt of the worker located in the well and continuously monitor him; - a cable (shunt) jumper is installed on the gas pipeline between the detachable parts of the gas pipeline in places that have been cleared of paint; - a worker in the well performs maintenance work on shut-off valves 20 at a time. 2.1; - upon completion of maintenance, checks the tightness of connections and fittings; - after lifting the worker, the well is checked for gas contamination; - the well cover is closed. 2.6 When performing maintenance on a ball valve installed in the ground without a well, under a carpet, the following types of work are performed: - the carpet cover is cleaned; - the carpet is checked for gas contamination using an instrument method through a hole in the carpet cover; - the carpet cover opens; - the carpet is cleaned of debris and water (if necessary); - check that there is no gas leakage under the ball valve rod cap by loosening the bolt; - the cap of the valve stem is removed and the operation of the valve is checked in the “open-closed” positions, without allowing the valve to close completely; - the serviceability of the drive device is checked; - the tightness of connections is checked using a foaming solution or an instrument method; - the carpet is checked for gas contamination and closed. 2.7 When servicing the valve, the following types of work are performed: - clean the valve body and bolted connections of the cover and flanges from dirt and rust; - tighten the stuffing box; - check the tightness of the flange connection bolts; - loosen and lubricate the drive; - check the tightness of the connections using a foaming solution or an instrument method. 2.8 When servicing a cone valve, the following types of work are performed: - clean the valve from dirt and rust, wipe with a rag; - adjust the smoothness of movement by tightening the tension nut; - check the tightness of the connections with a foaming solution. 2.9 When servicing a ball valve, the following types of work are performed: - clean the valve from dirt and rust, wipe with a rag; - open the tap; - center the smoothness of the move by tightening the tension nut; - check the tightness of the connections using a foaming solution or an instrument method. 2.10 If a gas leak is detected during maintenance of shut-off valves, it is necessary to eliminate the gas leak in the seals by tightening the seal or changing the stuffing box. When tightening the oil seal, the tension of the pressure axle box with cap bolts should be carried out evenly. One-sided tightening of the bolts can cause the axlebox flange to break. It is also necessary to ensure that the seal is not over-tightened, as this can lead to bending of the spindle and failure of the valve. 2.11 If a gas leak is detected during maintenance of shut-off valves installed in the well, those leaks that can be eliminated by replacing the gland packing in the valve or filling the chamber of the cone valve with lubricant are eliminated. In case of other leaks, work in the well should be stopped.

3 Work quality control

The tightness of connections and fittings installed on the gas pipeline and in the well is checked using a foaming solution or an instrument method.

4 Presentation of work results

Data on the work done on the maintenance of shut-off valves is entered into the passport for the gas pipeline and is stored for one year.

5 Special requirements

5.1 To carry out work on maintenance of shut-off valves, a work permit for performing gas hazardous work is issued in the form PB 12-529-03, which provides for the development and subsequent implementation of a set of measures for the preparation and safe performance of work. 5.2 Employees who have passed industrial safety certification to the extent corresponding to their job responsibilities and the profile of the work performed, and who have received permission to perform gas-hazardous work, are allowed to work. 5.3 Before performing work on maintenance of shut-off valves, the work manager is obliged to instruct workers about the technological sequence of operations and the necessary safety measures and record the completion of the instruction with the signatures of workers - members of the team in the work permit for performing gas hazardous work. 5.4 The availability and serviceability of personal protective equipment are determined when issuing a work permit. 5.5 The work manager is responsible for the availability of personal protective equipment for workers, their serviceability and skills in use. 5.6 After receiving the task, team workers are required to prepare: - the necessary personal protective equipment (hose gas mask, mittens, overalls, first aid kit, rescue belts and ropes) and check their serviceability; - tools, equipment and technical equipment necessary for performing the work, check their serviceability and compliance with safety requirements. 5.7 If gas is detected in the well, the worker, with the permission of the work supervisor, must go down into the well wearing a gas mask. 5.8 If there is a dangerous gas concentration (more than 20% of the lower flammability limit), descending into the well is prohibited. 5.9 When working in a gaseous environment, tools made of non-ferrous metal should be used. In the absence of such a tool, the cutting and striking parts of the tool must be lubricated with grease, grease or other grease to prevent the formation of a spark. 5.10 If a gas leak in the fittings, cracks, distortions or other damage is detected, work in the well must be stopped and the head of the service notified. 5.11 Before starting work on the roadway, the following safety measures must be taken: - workers and specialists carrying out the work must wear signal-colored vests; - install fences on the side of traffic at a distance of 5 m from the open well, and place warning signs at a distance of 10–15 m; - conduct continuous monitoring of passing vehicles; - if it is necessary to restrict traffic, the placement of road warning signs should be agreed upon with the traffic police. 5.12 You should only go down into the well using brackets or a ladder. When descending the brackets, you must make sure that they are securely fastened. The metal ladder must be of sufficient length with a device for securing it at the edge of the well. 5.13 Check the tightness of all welded, threaded, flange connections and gland seals using a foaming solution or an instrument method. 5.14 A worker descending into a well must wear special clothing and shoes without steel shoes and nails. 5.15 When cleaning fittings from rust and dirt, you must use safety glasses and gloves. 5.16 Painting the fittings in the well should be done with a hand brush (pneumatic spraying of paint is not allowed) and wearing a gauze mask. A limited amount of paint should be supplied to the well. During the painting period, the well must be constantly ventilated. Do not use dyes containing volatile solvents. The paint should be stored in a hermetically sealed container. 5.17 All team workers must be able to provide first aid for burns, bruises, suffocation, gas poisoning and electric shock. 5.18 If any serious damage is detected that could lead to an emergency and requires immediate repair, the ADS team should be called. Before the arrival of the ADS brigade, take safety measures (ventilate the well, prevent unauthorized persons from entering it and the appearance of open fire, etc.).

1. GENERAL INFORMATION.

This instruction is used in conjunction with the manufacturer's instructions.

Structurally, the valves consist of the following main components: a body with a ball valve, a drive and a control system.

Underground cranes additionally have a column with an extension spindle.

The tightness of the taps is ensured by sealing seats, which are located between the body of the taps and their ball valve.

On valves whose ball valves rotate on supports, the sealing rings (seats) are pressed against the ball valve by gas pressure and springs.

The valves, the ball valves of which rotate on supports, have a decompression hole in the upper part of the cases to relieve gas pressure from the valve body, as well as to control the tightness of the valves. At the bottom of the faucet bodies there is a hole for draining moisture and condensation. The tightness of these taps is checked by opening the decompression device after checking the position of the tap, first with gas and then with a hand pump: until the force on the pump handle sharply increases. If the tap is not tight, sealing paste is stuffed into the tap seat on the high pressure side. When complete tightness is achieved, to increase the reliability of closing the tap, seal the paste is also filled into the second seat on the low pressure side. In order to control the degree of tightness of the valve and prevent gas breakthrough through the seat on the low pressure side, the drainage and decompression device must be kept completely open during the entire time of fire or gas hazardous work. In this case, the gas must be discharged to the side, taking into account the direction of the wind: equipment and workers must be located on the windward side.

On floating valves, the valves (plugs) are pressed against the O-rings (seats).

If such valves are not tight, the sealing paste is packed into the valve seat on the low pressure side.

SAFETY WHEN CARRYING OUT WORK ON SHUT-OFF VALVES

Persons who have passed the knowledge test in the scope of this instruction, passed the examination on safety and technical regulations of main gas pipelines, and have mastered the operating instructions for ball valves are allowed to work on shut-off valves.

Rearrangement of taps must be carried out strictly with the permission of the management of the healthcare facility (KS). Inspection and repair of shut-off valves installed on gas communications is carried out without issuing a permit, but with mandatory registration in the Register of Gas Hazardous Work carried out without issuing a permit (depressurization of gas communications).

When carrying out work, use the tools specified in the operating instructions for the corresponding type of cranes.

Work on cranes should be carried out from special service platforms or ladders.

It is prohibited to use gas or oil pipes as supports or safety elements when working on cranes.

When dismantling and installing hydraulic cylinder and hydraulic cylinder drives, use special lifting equipment and devices.

All work on dismantling individual components and parts of the valves should be carried out after first making sure that there is no gas pressure in the relevant places.

When carrying out work on filling and refueling hydraulic systems of cranes, it is necessary to remove oil from the surface of the drive and the valve body.

Drainage of moisture and condensate from the body of a crane for underground use should be carried out after preliminary releasing the pressure through a decompression device.

Relieve pressure from the control system, valve body, as well as drain moisture and condensate carefully, in a direction that is safe for operating personnel.

It is prohibited to move valves using oxygen pressure energy.

It is prohibited to open the covers of limit switches on taps with remote control without removing the voltage from the power supply line.

It is prohibited to carry out maintenance work, vent gas, or move the valve during a thunderstorm.

If the valve valves, control unit, or impulse pipes freeze, heating should be done with heated air, steam or explosion-proof electric heating elements; it is prohibited to use open flame burners for these purposes.

When working with the electric drive of the crane, you should use the general provisions of the safety instructions when servicing electrical equipment under high voltage. Work on the electric drive should be carried out in the presence of an electrician on duty.

1. MEASURES TO EXCLUDE CASES OF UNPROCULAR

   OR INCORRECTLY REMOVED SHUT-OFF VALVES

Close shut-off devices (valves, valves, taps) on the pulse gas sampling lines to power the valve control unit.

Relieve pressure from the valve control system through a special decompression device designed for this purpose.

Disconnect the impulse tubes going to the opening and closing hydraulic cylinders.

Turn off the power supply to the electro-pneumatic valves of the crane control system at the main control room of the compressor station.

At the main control room of the compressor station, hang signs on the control keys of the corresponding cranes: “Do not turn on, people are working!”

On taps, where this is provided by the design, additionally turn off the power supply to the electro-pneumatic valves at the location where the tap is installed using a special key. After the power supply is turned off, a sign is posted on the crane control unit: “Do not turn it on, people are working!”

Disconnect the pulse gas tubes from the valve control unit.

Instead of disconnected pulse gas tubes, install plugs on the fittings of the control unit and seal them.

Install a bracket (block lock) on the hand pump, which prevents the possibility of opening the tap manually; on taps where there are two hand pumps, install such a bracket only on the hand pump to open the tap.

On cranes that have a manual mechanical drive, install a bracket (block lock) on the steering wheel (flywheel) in order to exclude the possibility of opening the crane with its help.

On cranes with an electric drive, it is necessary to turn off the power to the electric drive at the main control room of the compressor station and in the distribution box at the installation site of the crane. In the indicated places, post signs “Do not turn on, people are working!”

Place “Do not open” signs on all closed valves that separate the area where fire and gas hazardous work is being carried out from the gas pipeline.

4. MEASURES FOR RELIABLE CLOSING OF THE SHUT-OFF VALVES

After disconnecting a section of the gas pipeline from the place where fire and gas hazardous work is being carried out, make sure that the shut-off valves are in the “Closed” position. Control is carried out using the valve position indicator on the drive.

Check the position of the valves first using gas (by pressing the button, lever “Close”), and then using a hand pump (until the force on the pump handle sharply increases). On taps with a manual mechanical drive, closing is duplicated using a flywheel (drive wheel).

Check the degree of tightness of the taps by opening the decompression or drainage device. If the valve is completely sealed, a short-term release of gas from the cavity between the valve body and the ball valve will be observed through these devices. A constant release of gas will indicate insufficient tightness of the tap.

If a valve leak is detected, its tightness should be achieved by adjusting the piston stroke of the hydraulic (pneumatic) cylinder to “Closing”.

If the event according to clause 4. does not give the desired result, then pack the sealing paste into the valve seat on the high-pressure side, while monitoring the degree of tightness using the decompression or drainage device. (see paragraph 3)

When the valve is completely sealed according to claim 5. To increase the reliability of closing the valve, sealing paste is also poured into the second seat on the low pressure side.

If it is impossible to achieve complete tightness of the tap in accordance with clause 5. The sealing paste is stuffed into the second valve seat on the low pressure side. In this case, the degree of tightness is monitored through any gas sampling located on the low pressure side.

If the activity carried out according to clause 7 does not give the desired result, then the place where fire and gas hazardous work is being carried out must be shut off using inflatable rubber balloons (sealing devices).

If it is impossible to achieve complete tightness of the tap according to clause 4. and the design of the tap does not provide for filling with paste, then the taps of the adjacent sections are closed, and the work site is turned off in accordance with clause 8.

In order to control the tightness of the valve and prevent gas breakthrough through the seat on the low pressure side, the drainage and decompression device must be kept completely open during the entire period of fire and gas-hazardous work.

CHECKING AND INSPECTION OF CRANES

CONNECTION UNIT AND SECURITY VALVES

Inspection and testing of the connection node taps is carried out every shift.

When inspecting the connection point taps and security taps (including their internal jumpers), you must check:

position of the tap indicator and correspondence of its position to the indication on the control panel (“open”, “closed”);

position of the tap control handle switch: hand pump control mode (on taps with remote control, the handles must be in the “Remote control” position and secured with a stopper);

availability of pulse gas to control valves with filter purging;

condition of crane shelters and fences.

At the end of the inspection, the tap must be cleaned of dust, sand and oil stains, and in winter - of snow and ice.

Shelter doors must be in good condition, and in winter the approaches to them must be cleared of snow.

The doors of the shelters of security cranes and their lintels in the winter season must be in the open position (must be fixed in the open position) in order to ensure guaranteed and quick access to the control units of the cranes in emergency situations.

CHECKING AND INSPECTIONS OF CRANES

TECHNOLOGICAL PAIRING OF GPU

Checks and inspections of GPU process piping valves are carried out every shift and after each valve repositioning by shift personnel and include the following checks:

compliance of the position of the shut-off valves with the “Instructions on the position of the shut-off valves of the process piping of gas compressor units that are in operation, standby and under repair.”

completeness of all crane components;

position of the tap indicator and correspondence of its position to the indication on the control panel (“open”, “closed”);

the presence of a pump handle for manual drive of the crane;

condition of bolted and nipple connections, tighten them if necessary;

position of the tap control handle switch: hand pump control mode (on taps with remote control, the handles must be in the “Remote control” position and secured with a stopper);

tightness of seals of the crane spindle, pistons, rods, cylinders of the crane drive;

external condition of crane control cables;

sealing of terminal boxes, valve control units;

presence of gas leaks, eliminate if possible;

Checking the correct installation of the valve in the crane using a hand pump or steering wheel using the position indicator: checking the stroke of the crane.

Upon completion of the inspection, the tap must be cleaned of dust, sand and oil stains, and in winter, of snow and ice.

The shift engineer (EGO engineer) must be notified of all identified malfunctions and a corresponding entry must be made in the “List of Defects and Violations” at the 1st level of the agro-industrial complex.

7. MAINTENANCE (MAINTENANCE) OF SHUT-OFF VALVES

Types of valve maintenance work:

scheduled inspection (TO-1);

seasonal maintenance (TO-2);

current repair (TR);

technical diagnostics (TD);

medium repair (SR);

major repairs (CR);

maintenance during storage (maintenance during storage);

maintenance during conservation of an object (maintenance during conservation).

Routine maintenance (MOT)- called a set of operations or an operation to maintain the functionality or serviceability of a product when used for its intended purpose, waiting, storage and transportation. [GOST 18322, clause 1].

Routine maintenance includes the following types:

Periodic inspection of TO-1 – a set of works carried out once a month. The results of the periodic inspection are entered into the valve passport in the section “Accounting for PPR of shut-off valves” (see Appendix 1).

-Seasonal maintenance TO-2– a set of works carried out once every 6 months, including the scope of work TO-1. Seasonal maintenance of TO-2 is carried out in preparing the valves for the autumn-winter and summer periods of operation. Work on TO-2 is also carried out before carrying out repair work related to disconnecting a section of the main gas pipeline. The results of seasonal maintenance are entered into the valve passport in the section “Accounting for PPR of shut-off valves” (see Appendix 1).

Current repairs (TR ) - Repairs performed to ensure or restore the functionality of the product and consist of replacing and/or restoring individual parts. [GOST 18322-78 (ST SEV 5151-85), page 1]

Current repairs are carried out based on the results of TO-1,TO-2 .

When carrying out routine repairs, the following is carried out:

cleaning, priming and painting the paint surfaces of the housing, extension column and drive that have become corroded;

tightening of all threaded connections of the housing, extension column, drive and attachments;

cleaning filter driers and replacing the adsorbent with its subsequent regeneration;

revision of the drive hydraulic system by removing air from hydraulic cylinders, moisture and sludge from tubes and cylinders;

replacing the damper fluid of the drive hydraulic system;

revision of the sealing system of the valve seats and spindle: tubes, fittings and lubrication multipliers;

packing cleaning and sealing lubricant into the valve seats and spindle;

revision of the manual pump-backup and operating mode switches;

inspection of screw-lever parts of the gearbox, rotary-rotary, rack and pinion drive mechanism;

revision of the pulse gas supply system with adjustment of relief and bypass valves;

inspection of instrumentation and automation equipment, measurement of insulation and grounding resistance.

The results of current repairs are entered into the valve passport in the section “Accounting for PPR shut-off valves” (see Appendix 1).

Technical diagnostics (TD ): Determination of the technical condition of the object.

[GOST 20911, clause 4]

Technical diagnostics are carried out periodically, every 10 years of operation, and also in cases where:

As a result of maintenance, an unsatisfactory condition of individual components and parts was revealed (lack of tightness, jamming or long time for moving the valve, knocking, progressive corrosive wear, cracking, etc.), which can lead to critical failures, or repeated failures occurred ;

operation was carried out under the influence of factors exceeding the design parameters (temperature, pressure and external power loads), or was subject to emergency impacts (fire, freezing of water in the housing, seismic impact, etc.);

the service life (resource) established by the design and normative-technical documentation has been exhausted or the service life exceeds 30 years (if the technical documentation does not contain information about the assigned indicators);

the main pipeline is being reconstructed, modernized or overhauled.

Technical diagnostics are carried out according to methods approved in accordance with the established procedure. The service life of valves is assessed, as a rule, as part of an industrial safety examination carried out in accordance with RD 03-484-02, PB 03-246-98 and STO Gazprom 2-3.5-045.

The main types of work when carrying out technical diagnostics of valves include:

analysis, processing and examination of a set of regulatory and technical documentation (passports, manuals, schedules, maintenance and repair logs, acts, etc.);

visual and instrumental-measuring control of main components and parts;

monitoring the performance (functioning) of the drive;

control of seal tightness;

monitoring the condition of the metal and welded joints of the body using non-destructive methods (while extending the service life);

assessment of technical condition (with the issuance of a conclusion on the possibility of extending the period of safe operation or establishing a new assigned period (resource) of operation, replacement, repair, dismantling of individual components, etc.).

The results of technical diagnostics are entered into the valve passport in the section “Accounting for PPR of shut-off valves”.

Medium repair (SR) ): Repairs carried out to restore serviceability and partially restore the service life of products with the replacement or restoration of components of a limited range and monitoring the technical condition of the components, carried out to the extent established in the regulatory and technical documentation. [GOST 18322-78 (ST SEV 5151-85 ), page 1].

Average repairs of fittings are carried out based on the results of technical diagnostics.

This type of repair is carried out without dismantling the pipeline.

When carrying out average repairs of fittings, the following types of work can be carried out:

modernization of the pneumohydraulic drive control system;

repair of hydraulic cylinders, replacement of piston seals;

replacement of the spindle seal, oil seal with sealing lubricant packing;

repair or replacement of a manual backup pump, gas sampling valves, pulse gas tubes, operating mode switches and throttles-regulators of damper fluid flow;

repair or replacement of tubes, fittings and lubrication multipliers of the valve seal system;

repair or replacement of screw-lever parts of the gearbox, rotary-rotary, rack and pinion drive mechanism;

replacing the seal of the flange connection of the housing or extension column;

repair or replacement of the yoke bearing;

electric drive replacement;

repair of the damping device (shock absorber);

repair or replacement of instrumentation and automation equipment;

other repairs.

Major repairs (KR ): Repairs performed to restore serviceability and complete or close to full restoration of the life of a product with the replacement or restoration of any of its parts, including basic ones. [GOST 18322-78 (ST SEV 5151-85), page 1]

Major repairs of valves are carried out based on the results of technical diagnostics.

This type of repair is carried out with the dismantling of the injection molding machine in a specialized organization.

During a major overhaul, all parts and assemblies are completely disassembled and defective, restored or replaced as a result of corrosion or excessive mechanical wear. Overhaul of valves should ensure the safety of its further operation.

The scope of major repairs is determined on the basis of the defective list and includes the following operations:

restoration of seal tightness;

repair of body parts;

drive repair;

replacement of defective worn parts.

After a major overhaul, the fittings are subjected to acceptance tests in a specialized organization.

During a major overhaul, the requirements for the manufacture of fittings are observed in terms of the materials used and design features. A specialized organization is obliged to carry out the entire range of measures to ensure the level of product safety determined by the manufacturer, specified in the regulatory and technical documentation. During repairs, it is possible to control the implementation of all technological operations on which safety depends.

Deviations from the design during major repairs of valves are agreed with the manufacturer. The safety level of such fittings must not be reduced.

If the marking is damaged during the repair process, a specialized organization is obliged to restore it to the body.

Repair of valves is carried out by trained personnel with the necessary qualifications, who have studied the operating manual (repair documentation) in compliance with labor protection and safety requirements.

Based on the results of the overhaul, the following information is entered into the valve passport:

name of the specialized repair organization (division);

volume (composition) of repairs;

material of elements introduced into the reinforcement;

soldering surfacing material;

brand of electrodes for welding;

values ​​of reliability indicators - when they change;

tests performed and their results;

values ​​of assigned indicators, in case of their extension.

Storage Maintenance .

The volumes, storage conditions, procedure for using and updating emergency stock injection pumps are determined in accordance with regulatory documentation. The shelf life of fittings should not exceed 5 years.

When servicing emergency valves in storage, check:

availability of operational and accompanying documentation;

completeness according to the passport;

integrity and tightness of fastening of plugs, providing protection of butt edges for welding;

labeling;

absence of dents, burrs, mechanical damage, and corrosion on the body and ends;

absence of delaminations of any size at the ends of the pipes;

the presence of conservation lubricant on the internal surfaces of the valve, pipes and on all unpainted surfaces of the spindle and drive;

condition of welds.

Maintenance during conservation of an object .

When servicing the fittings of an object under conservation, the following is checked:

completeness and integrity of main components and parts;

tightness of threaded, welded and flanged connections of main units and parts;

condition of the paintwork of the body, main components and parts;

presence and level of damper fluid in the drive hydraulic system;

integrity and correct positions of hand pump distributor handles, gas sampling valves, operating mode switches and damper fluid flow control throttles.

The results of the maintenance are recorded in the valve certificate.

Cut-out taps must be preserved. Disassembly of drives and attachments is not allowed. Draining hydraulic fluid from the drive hydraulic system is strictly prohibited.
Cranes are shipped for repair only after receiving additional instructions.
New (overhauled) replacement cranes undergo inspection and maintenance to the following extent:

checking the presence of a factory passport for the crane;

checking the completeness of attachments (lubricant supply pipes, drainage, gas extraction, valve fittings, check valves, keys, pins, fasteners, hand pump, oil pipes, ECU, limit switches, etc.);

carrying out an inspection of the hydraulic system, if necessary, cleaning it from sludge and dirt;

filling the drive hydraulic system with hydraulic fluid;

carrying out complete installation of attachments;

testing the functionality of the valve with a manual override for “closing” and “opening” while simultaneously checking the correct installation of the extreme positions of the ball valve;

welding of pipe blanks with spherical plugs to the valve;

carrying out hydraulic tests of the crane for the tightness of the valve and spindle seals, hydraulic testing for the strength of welds, with the preparation of relevant reports.

Packing lubricant (cyatim, gas valve lubricant, sealing paste or similar) into both valve seals and the spindle seal.

Requirements for shut-off valves during inspection.

The tap is numbered.

The nameplate is not painted over.

Pressure gauges on taps made in Czechoslovakia are not painted over.

All fasteners are installed and tightened.

There is a key for the connection “faucet body - drive”, there is no play.

The valve position indicator is fixed.

The valve's end position plate (“open”, “closed”) is marked.

Oil has been filled into the hydraulic cylinders and an entry has been made in the valve form.

There are no traces of oil leaks.

The hand pump has been inspected and is operational.

The pump rod is lubricated with grease.

The pump rod is fixed in the designed position.

There is a pump handle.

The switch positions for manual adjustment are indicated (“open”, “closed”).

On domestic taps, the spool position lock rotates freely.

On domestic cranes, the multiplier is filled with crane grease.

The fittings of the hydraulic cylinders and cylinders are sealed.

The hatches for determining the position of the scenes are sealed.

The tubes of the packing tubes, drainage and own gas sampling are fixed to the column.

The ground-to-air transition is insulated on the tubes of the packing tanks, drainage and own gas extractions, and on the column.

The threaded connections of the stuffers and the drain valve must be protected with grease from dirt and precipitation.

There is a diagram of the crane assembly. The crane assembly diagram is tied to the area.

There is a fencing for the crane assembly. Safety signs have been installed in accordance with the requirements of PTEMG.

There is no rust on the body, dirt, or foreign objects on the drive.

Gas extraction risers DN50 are closed at the top to prevent moisture from entering.

On Du300 “candles” the “firecrackers” are in the closed position.

The valve position indicators are highlighted in red.

On hand-operated valves, hydraulic cylinders or expansion tanks are connected to the atmosphere (this prevents precipitation from entering the hydraulic cylinders: the presence of L-shaped goosenecks).

The presence of a sign on the tap indicating the type of hydraulic fluid filled.

Presence of “O” and “Z” inscriptions on hydraulic cylinders

The presence of inscriptions “O” and “Z” on hydraulic cylinders, indicating the connection points for pumps for emergency relocation of cranes.

The tap pump switch is in the required position: remotely controlled in the “Dist” position, and the rest - in accordance with the requirements of the ND.

Appendix 3.

Actions of personnel to relocate cranes in emergency situations

If you do not move the valves remotely, you must perform the following operations:

1. If there is pulse gas and the electronic control unit is in good working order:

1. Reposition the faucet by pressing the solenoid key “Open” or “Close” in the electronic control panel and holding the valve until it is completely repositioned.

   2. If there is no pulse gas and the electronic control unit is faulty:

shut off and bleed the pulse gas;

set the pump operating mode switch to the “Open” or “Closed” position so that it is directed towards the corresponding inscription, and the lock (threaded or ball) coincides with the groove on the pump body;

move the valve using a hand pump to the extreme position.

Note : In the event of an accident (when it is urgently necessary to move the valve) and with large diameters of the valves being adjusted (Du1400) or insufficient (low) pump performance (Du1000-1400 valves), it is necessary to simultaneously prepare a high-pressure hose for moving the valve with pulse gas according to paragraph 3 (see below).

3. Opening or closing a valve in the event of a malfunction of the electronic control unit, manual adjustment pump and the presence of pulse gas (using a high-pressure motor):

check the position of the pump operating mode switch (set to the “Remote” position);

connect the high pressure hose (HPH) to the pulse gas riser and the fitting of the corresponding hydraulic cylinder (closing or opening);

Note: If there are gas cavities in hydraulic cylinders, gas must be supplied to the corresponding gas cavity, or, if not, to the corresponding oil cavity.

smoothly open the pulse gas valve and supply gas to the corresponding hydraulic cylinder and rearrange the valve;

upon reaching the extreme position of the valve, turn off the pulse gas and relieve pressure from the hydraulic cylinder through the RVD purge valve.

4. Opening or closing a valve in the event of a malfunction of the electronic control unit, the manual adjustment pump and the absence of pulse gas (using an emergency adjustment pump):

close the pulse gas tap (from the riser, local taps) and bleed the gas;

set the pump operating mode switch to an intermediate position (for example, between “O” and “D”);

at the top point of the hydraulic cylinder connecting the oil lines, open the air vents marked “O” and “Z”;

connect the RVD to the air vents and connect the other end of the corresponding RVD to the pump to relocate the valve, and the RVD of the opposite hydraulic cylinder into a mobile container (and not to the pump fitting);

Note:

1. By placing a container with tap oil above the pump, provide support at the suction of the emergency changeover pump.

2. Drain the crane oil from the hydraulic cylinder into a mobile container (and not into the pump fitting to prevent air from entering the pump - if there is air in the hydraulic cylinder, and monitor the pump’s performance).

move the tap with the pump to the extreme position.

Important information