How to maintain plastic valves

Update:21-07-2022
Summary:Plastic valve storage and maintenance ◆The purpose of storage and maintenance is to prevent the plastic valve from bein...
Plastic valve storage and maintenance
◆The purpose of storage and maintenance is to prevent the plastic valve from being damaged or reducing the quality during storage. In fact, improper storage is one of the important reasons for valve damage
◆Valves should be kept in an orderly manner. Small valves should be placed on the shelves, and large valves can be arranged on the floor of the warehouse. They should not be piled up randomly, and the flange connection surface should not touch the ground. This is not only for aesthetics, but mainly to protect the valve from damage
◆Due to improper storage and handling, the handwheel is broken, the valve stem is slanted, the fixing nut between the handwheel and the valve stem is loose and lost, etc. These unnecessary losses should be avoided.
◆For valves that will not be used in a short period of time, the asbestos packing should be taken out to avoid electrochemical corrosion and damage to the valve stem.
◆Check the valve that has just entered the warehouse. If rainwater or dirt enters during transportation, it should be wiped clean and then stored.
◆The inlet and outlet of the plastic valve should be sealed with wax paper or plastic sheet to prevent dirt from entering
◆Apply anti-rust oil to the valve processing surface that can rust in the atmosphere to protect it
◆The valve placed outdoors must be covered with rain-proof and dust-proof items such as linoleum or tarpaulin. The warehouse where the valves are stored should be kept clean and dry
Use and maintenance of plastic valves
◆The purpose of use and maintenance is to prolong the life of the valve and ensure reliable opening and closing
◆The thread of the valve stem is often rubbed with the valve stem nut, and a little yellow dry oil, molybdenum disulfide or graphite powder should be applied to lubricate it.
◆For valves that are not frequently opened and closed, turn the handwheel regularly, and add lubricant to the valve stem thread to prevent biting
◆For outdoor valves, a protective cover should be added to the valve stem to prevent rain, snow, dust and rust.
◆If the valve is mechanically ready to move, add lubricating oil to the gearbox on time
◆ Always keep the valve clean
◆ Always check and maintain the integrity of the other parts of the valve. If the fixing nut of the handwheel falls off, it must be matched and cannot be used properly, otherwise it will grind the square on the upper part of the valve stem, gradually lose the reliability of cooperation, and even cannot be started.
◆Do not rely on the valve to support other heavy objects, and do not stand on the valve
◆The valve stem, especially the threaded part, should be wiped frequently, and the lubricant that has been soiled by dust should be replaced with a new one, because the dust contains hard debris, which is easy to wear the thread and the surface of the valve stem, which affects the service life.
Maintenance of plastic valve packing
◆The packing is directly related to the key seal of leakage when the plastic valve is switched on and off. If the packing fails and causes leakage, the valve is equivalent to failure, especially the valve of the urea pipeline, because of its high temperature, it is more harmful to corrosion, and the packing is easy Ageing. Enhanced maintenance can extend the life of the packing
◆When the valve leaves the factory, in order to ensure the elasticity of the packing, it is generally subject to the static pressure test and no leakage. After the valve is installed in the pipeline, due to factors such as temperature, extravasation may occur. At this time, the nuts on both sides of the packing gland should be tightened in time, as long as there is no leakage, and if there is extravasation in the future, tighten it again, not once Tighten, so as not to lose elasticity of the packing and loss of sealing performance
◆Some plastic valve packings are filled with molybdenum disulfide lubricating paste. After using for several months, the corresponding lubricating grease should be added in time. When it is found that the packing needs to be supplemented, the corresponding packing should be added in time to ensure its sealing performance.
Maintenance of plastic valve transmission parts
◆During the opening and closing of the valve, the lubricating oil added will be continuously lost, and the effect of temperature, corrosion and other factors will also make the lubricating oil continue to dry up. Therefore, the transmission parts of the valve should be checked frequently, and the oil shortage should be replenished in time to prevent the increase of wear due to lack of lubricant, resulting in inflexible transmission or failure of the case.
Maintenance of plastic valves during grease injection
◆When injecting grease into plastic valves, the amount of grease injection is often ignored. After the grease injection gun is refueled, the operator selects the valve and the grease injection connection method, and then performs the grease injection operation. There are two situations: on the one hand, the amount of grease injection is small and the grease injection is insufficient, and the sealing surface wears quickly due to the lack of lubricant. On the other hand, excessive grease injection results in waste. The reason is that there is no precise calculation of the sealing capacity of different valves according to the valve type category. The sealing capacity can be calculated based on the valve size and type, and then a reasonable amount of grease can be injected.
◆When the valve is greased, the pressure problem is often ignored. During the grease injection operation, the grease injection pressure changes regularly with peaks and valleys. The pressure is too low, the seal leaks or fails, the pressure is too high, the grease injection port is blocked, the sealing inner grease is hardened, or the sealing ring is locked with the valve ball and valve plate. Usually, when the grease injection pressure is too low, the injected grease mostly flows into the bottom of the valve cavity, which usually occurs in small gate valves. If the grease injection pressure is too high, on the one hand, check the grease injection nozzle, and replace it if the grease hole is blocked. . In addition, the sealing type and sealing material also affect the grease injection pressure. Different sealing forms have different grease injection pressures. Generally, the grease injection pressure of hard seals is higher than that of soft seals.
◆When injecting grease into the valve, pay attention to the problem that the valve is in the switch position. The ball valve is generally in the open position during maintenance, and in special cases, it is selected to be closed for maintenance. Other valves can not be regarded as open position. The gate valve must be closed during maintenance to ensure that the grease fills the sealing groove along the sealing ring. If it is open, the sealing grease will drop directly into the flow channel or valve cavity, causing waste.
◆When injecting grease into the valve, the effect of grease injection is often ignored. During the grease injection operation, the pressure, grease injection volume, and switch position are all normal. However, in order to ensure the grease injection effect of the valve, it is sometimes necessary to open or close the valve, check the lubrication effect, and confirm that the surface of the valve ball or gate is evenly lubricated
◆When injecting grease, pay attention to the problem of valve body blowdown and wire plug pressure relief. After the valve pressing test, the gas and moisture in the valve cavity of the sealing cavity will increase due to the increase of the ambient temperature. When injecting grease, it is necessary to discharge the sewage and release the pressure first, so as to facilitate the smooth progress of the grease injection. The air and moisture in the sealed cavity are fully replaced after grease injection. The valve cavity pressure is released in time, which also ensures the safety of the valve. After the grease injection, be sure to tighten the drain and pressure relief plugs to prevent accidents.
◆When injecting grease, pay attention to the problem of uniform grease. During normal grease injection, the grease discharge hole closest to the grease injection port will discharge grease first, then to the low point, and finally to the high point, and the grease will be discharged one by one. If it does not follow the rules or there is no fat, it proves that there is a blockage, and it should be cleaned in time.
◆Also observe the issue that the valve diameter is flush with the sealing ring seat when injecting grease. For example, for a ball valve, if there is interference in the opening position, adjust the opening position limiter inward to confirm that the diameter is straight and then lock. Adjusting the limit should not only pursue the opening or closing position, but consider the whole. If the opening position is flush and the closing position is not in place, the valve will not close tightly. In the same way, if the adjustment of the closed position is in place, the corresponding adjustment of the open position should also be considered. Ensuring right-angle travel of the valve
◆After grease injection, be sure to seal the grease injection port. To avoid the entry of impurities, or the oxidation of lipids at the grease injection port, the cover should be coated with anti-rust grease to avoid rusting. for the next operation
◆When injecting grease, it is also necessary to consider specific problems in the sequential transportation of oil products in the future. Given the different qualities of diesel and gasoline, the scour and disintegration ability of gasoline should be considered. In the future valve operation, when encountering gasoline section operations, replenish grease in time to prevent wear and tear.
◆When injecting grease, do not neglect the grease injection at the valve stem. There are sliding bushings or packings on the valve shaft, which also needs to be kept lubricated to reduce the frictional resistance during operation. If lubrication cannot be ensured, the torque will increase the wear parts during electric operation, and the switch will be laborious during manual operation.
◆Some ball valves are marked with arrows. If there is no English FIOW handwriting, it is the direction of action of the sealing seat, not as a reference for the flow direction of the medium, and the direction of the valve self-leakage is opposite. Typically, double seated ball valves have bidirectional flow
◆When maintaining the valve, also pay attention to the problem of water inflow in the electric head and its transmission mechanism. Especially the rain that seeps in during the rainy season. One is to rust the transmission mechanism or the transmission sleeve, and the other is to freeze in winter. When the electric valve is operated, the torque is too large, and the damage to the transmission parts will make the motor no-load or over-torque protection trip, and the electric operation cannot be realized. The transmission parts are damaged, and manual operation cannot be carried out. After the over-torque protection action, the manual operation is also unable to switch, such as forced operation, it will damage the internal alloy parts
The maintenance of plastic valves must be treated in a scientific manner, so that the valve maintenance work can achieve its due effect and application purpose. In order to make production run normally, reduce parking and increase economic benefits, in terms of valves, these three points must be done well
First, the correct selection of valves is the basis
Second, the correct use of the valve is the most critical
3. Correct maintenance is the guaranteeHow to maintain plastic valves
Plastic valve storage and maintenance
◆The purpose of storage and maintenance is to prevent the plastic valve from being damaged or reducing the quality during storage. In fact, improper storage is one of the important reasons for valve damage
◆Valves should be kept in an orderly manner. Small valves should be placed on the shelves, and large valves can be arranged on the floor of the warehouse. They should not be piled up randomly, and the flange connection surface should not touch the ground. This is not only for aesthetics, but mainly to protect the valve from damage
◆Due to improper storage and handling, the handwheel is broken, the valve stem is slanted, the fixing nut between the handwheel and the valve stem is loose and lost, etc. These unnecessary losses should be avoided.
◆For valves that will not be used in a short period of time, the asbestos packing should be taken out to avoid electrochemical corrosion and damage to the valve stem.
◆Check the valve that has just entered the warehouse. If rainwater or dirt enters during transportation, it should be wiped clean and then stored.
◆The inlet and outlet of the plastic valve should be sealed with wax paper or plastic sheet to prevent dirt from entering
◆Apply anti-rust oil to the valve processing surface that can rust in the atmosphere to protect it
◆The valve placed outdoors must be covered with rain-proof and dust-proof items such as linoleum or tarpaulin. The warehouse where the valves are stored should be kept clean and dry
Use and maintenance of plastic valves
◆The purpose of use and maintenance is to prolong the life of the valve and ensure reliable opening and closing
◆The thread of the valve stem is often rubbed with the valve stem nut, and a little yellow dry oil, molybdenum disulfide or graphite powder should be applied to lubricate it.
◆For valves that are not frequently opened and closed, turn the handwheel regularly, and add lubricant to the valve stem thread to prevent biting
◆For outdoor valves, a protective cover should be added to the valve stem to prevent rain, snow, dust and rust.
◆If the valve is mechanically ready to move, add lubricating oil to the gearbox on time
◆ Always keep the valve clean
◆ Always check and maintain the integrity of the other parts of the valve. If the fixing nut of the handwheel falls off, it must be matched and cannot be used properly, otherwise it will grind the square on the upper part of the valve stem, gradually lose the reliability of cooperation, and even cannot be started.
◆Do not rely on the valve to support other heavy objects, and do not stand on the valve
◆The valve stem, especially the threaded part, should be wiped frequently, and the lubricant that has been soiled by dust should be replaced with a new one, because the dust contains hard debris, which is easy to wear the thread and the surface of the valve stem, which affects the service life.
Maintenance of plastic valve packing
◆The packing is directly related to the key seal of leakage when the plastic valve is switched on and off. If the packing fails and causes leakage, the valve is equivalent to failure, especially the valve of the urea pipeline, because of its high temperature, it is more harmful to corrosion, and the packing is easy Ageing. Enhanced maintenance can extend the life of the packing
◆When the valve leaves the factory, in order to ensure the elasticity of the packing, it is generally subject to the static pressure test and no leakage. After the valve is installed in the pipeline, due to factors such as temperature, extravasation may occur. At this time, the nuts on both sides of the packing gland should be tightened in time, as long as there is no leakage, and if there is extravasation in the future, tighten it again, not once Tighten, so as not to lose elasticity of the packing and loss of sealing performance
◆Some plastic valve packings are filled with molybdenum disulfide lubricating paste. After using for several months, the corresponding lubricating grease should be added in time. When it is found that the packing needs to be supplemented, the corresponding packing should be added in time to ensure its sealing performance.
Maintenance of plastic valve transmission parts
◆During the opening and closing of the valve, the lubricating oil added will be continuously lost, and the effect of temperature, corrosion and other factors will also make the lubricating oil continue to dry up. Therefore, the transmission parts of the valve should be checked frequently, and the oil shortage should be replenished in time to prevent the increase of wear due to lack of lubricant, resulting in inflexible transmission or failure of the case.
Maintenance of plastic valves during grease injection
◆When injecting grease into plastic valves, the amount of grease injection is often ignored. After the grease injection gun is refueled, the operator selects the valve and the grease injection connection method, and then performs the grease injection operation. There are two situations: on the one hand, the amount of grease injection is small and the grease injection is insufficient, and the sealing surface wears quickly due to the lack of lubricant. On the other hand, excessive grease injection results in waste. The reason is that there is no precise calculation of the sealing capacity of different valves according to the valve type category. The sealing capacity can be calculated based on the valve size and type, and then a reasonable amount of grease can be injected.
◆When the valve is greased, the pressure problem is often ignored. During the grease injection operation, the grease injection pressure changes regularly with peaks and valleys. The pressure is too low, the seal leaks or fails, the pressure is too high, the grease injection port is blocked, the sealing inner grease is hardened, or the sealing ring is locked with the valve ball and valve plate. Usually, when the grease injection pressure is too low, the injected grease mostly flows into the bottom of the valve cavity, which usually occurs in small gate valves. If the grease injection pressure is too high, on the one hand, check the grease injection nozzle, and replace it if the grease hole is blocked. . In addition, the sealing type and sealing material also affect the grease injection pressure. Different sealing forms have different grease injection pressures. Generally, the grease injection pressure of hard seals is higher than that of soft seals.
◆When injecting grease into the valve, pay attention to the problem that the valve is in the switch position. The ball valve is generally in the open position during maintenance, and in special cases, it is selected to be closed for maintenance. Other valves can not be regarded as open position. The gate valve must be closed during maintenance to ensure that the grease fills the sealing groove along the sealing ring. If it is open, the sealing grease will drop directly into the flow channel or valve cavity, causing waste.
◆When injecting grease into the valve, the effect of grease injection is often ignored. During the grease injection operation, the pressure, grease injection volume, and switch position are all normal. However, in order to ensure the grease injection effect of the valve, it is sometimes necessary to open or close the valve, check the lubrication effect, and confirm that the surface of the valve ball or gate is evenly lubricated
◆When injecting grease, pay attention to the problem of valve body blowdown and wire plug pressure relief. After the valve pressing test, the gas and moisture in the valve cavity of the sealing cavity will increase due to the increase of the ambient temperature. When injecting grease, it is necessary to discharge the sewage and release the pressure first, so as to facilitate the smooth progress of the grease injection. The air and moisture in the sealed cavity are fully replaced after grease injection. The valve cavity pressure is released in time, which also ensures the safety of the valve. After the grease injection, be sure to tighten the drain and pressure relief plugs to prevent accidents.
◆When injecting grease, pay attention to the problem of uniform grease. During normal grease injection, the grease discharge hole closest to the grease injection port will discharge grease first, then to the low point, and finally to the high point, and the grease will be discharged one by one. If it does not follow the rules or there is no fat, it proves that there is a blockage, and it should be cleaned in time.
◆Also observe the issue that the valve diameter is flush with the sealing ring seat when injecting grease. For example, for a ball valve, if there is interference in the opening position, adjust the opening position limiter inward to confirm that the diameter is straight and then lock. Adjusting the limit should not only pursue the opening or closing position, but consider the whole. If the opening position is flush and the closing position is not in place, the valve will not close tightly. In the same way, if the adjustment of the closed position is in place, the corresponding adjustment of the open position should also be considered. Ensuring right-angle travel of the valve
◆After grease injection, be sure to seal the grease injection port. To avoid the entry of impurities, or the oxidation of lipids at the grease injection port, the cover should be coated with anti-rust grease to avoid rusting. for the next operation
◆When injecting grease, it is also necessary to consider specific problems in the sequential transportation of oil products in the future. Given the different qualities of diesel and gasoline, the scour and disintegration ability of gasoline should be considered. In the future valve operation, when encountering gasoline section operations, replenish grease in time to prevent wear and tear.
◆When injecting grease, do not neglect the grease injection at the valve stem. There are sliding bushings or packings on the valve shaft, which also needs to be kept lubricated to reduce the frictional resistance during operation. If lubrication cannot be ensured, the torque will increase the wear parts during electric operation, and the switch will be laborious during manual operation.
◆Some ball valves are marked with arrows. If there is no English FIOW handwriting, it is the direction of action of the sealing seat, not as a reference for the flow direction of the medium, and the direction of the valve self-leakage is opposite. Typically, double seated ball valves have bidirectional flow
◆When maintaining the valve, also pay attention to the problem of water inflow in the electric head and its transmission mechanism. Especially the rain that seeps in during the rainy season. One is to rust the transmission mechanism or the transmission sleeve, and the other is to freeze in winter. When the electric valve is operated, the torque is too large, and the damage to the transmission parts will make the motor no-load or over-torque protection trip, and the electric operation cannot be realized. The transmission parts are damaged, and manual operation cannot be carried out. After the over-torque protection action, the manual operation is also unable to switch, such as forced operation, it will damage the internal alloy parts
The maintenance of plastic valves must be treated in a scientific manner, so that the valve maintenance work can achieve its due effect and application purpose. In order to make production run normally, reduce parking and increase economic benefits, in terms of valves, these three points must be done well
First, the correct selection of valves is the basis
Second, the correct use of the valve is the most critical
3. Correct maintenance is the guarantee
UPVC SOCKET DOUBLE UNION DIAPHRAGM VALVE

Media: Acid

Temperature: Ordinary Temperature

Actuator: Manual

Connection: Welded Diaphragm Valve

Material: Plastic-UPVC

Structure: Weir Diaphragm Valve

Valve type: Weir

Connection: Socket welding/fusion

Model NO.: G41F-6S

Pressure: Low Pressure

Flow Direction: Bidirectional

Function: Field Bus

Usage: Flow Control

Standard: DIN, GB, ANSI, BSW, JIS

Size: Dn15-Dn100

Trademark: Baodi

Transport Package: Carton/Plywood Box

Specification: ANSI JIS GB DIN

Specification: 1/2"-2"

Origin: China

HS Code: 8481804090

End connection: Socket

Working pressure: 0.6Mpa

Working temperature: UPVC- ~40ºC-+60ºC