Daily maintenance of the valve 1, the valve should be kept dry and ventilated indoor, access blocked at both ends. 2, long-term storage of the valve should be regularly checked to remove dirt, and coated with anti-rust oil on the processing surface. 3, after installation, should be regularly checked, the main inspection items: (1) sealing surface wear and tear. (2) trapezoidal stem and stem nut thread wear. (3) whether the filler is out of date failure, if damaged should be promptly replaced. (4) valve repair assembly, the sealing performance test should be carried out. Running valves, all kinds of valve should be complete, intact. Flange and bracket bolts indispensable, the thread should be intact, does not allow loose phenomenon. Tightening nuts on the handwheel should be tightened promptly if they are loose to avoid wearing the connection or losing the handwheel and nameplate. Handwheel if lost, not allowed to replace with a live wrench, should be timely and complete. Packing gland does not allow skew or no pre-clearance. On the vulnerable to rain, snow, dust, wind and other dirt contaminated valve environment, the valve stem to install the protective cover. The ruler on the valve should be kept intact, accurate and clear. Valve seals, caps, pneumatic accessories, etc. should be complete and intact. Insulation jacket should be no depression, cracks. Not allowed on the operation of the valve on the beat, standing or supporting heavy objects; especially non-metallic valves and cast iron valves, but also to prohibit the valve when the maintenance of grease injection work before the start of welding and put into operation after the valve professional conservation work, Valve service plays a crucial role in the production and operation. Correct and orderly maintenance will protect the valve, make the valve function properly and prolong the service life of the valve. Valve maintenance work seems simple, it is not. Often overlooked aspects of work. First, the valve fat, often overlook the problem of fat volume. After the grease gun, the operator chooses the valve and grease coupling method, the grease injection operation. There are two situations: on the one hand less fat less lipid injection, sealing surface due to the lack of lubricant to speed up wear and tear. On the other hand excessive fat, resulting in waste. There is no exact calculation of the different valve seal capacities based on the type of valve. The valve size and type can be calculated seal capacity, and then a reasonable amount of grease into the appropriate. Second, the valve fat, often ignore the pressure problem. In the grease injection operation, lipid injection pressure showed a regular change in the peak valley. Pressure is too low, the seal leak or failure, the pressure is too high, the injection port blocked, seal the lipid hardened or seal ring and valve ball, valve plate lock. Usually grease injection pressure is too low, more grease into the valve cavity flow at the bottom, usually occurs in the small gate valve. The grease injection pressure is too high, on the one hand check the grease nozzle, if the obstruction of the case identified to be replaced; on the other hand, lipid sclerosis, to use cleaning fluid, repeated softening failure of sealant, and injected new grease replacement . In addition, the sealing model and sealing material, but also affect the injection pressure, different sealing forms have different injection pressure, the general situation of hard sealing grease pressure is higher than the soft seal. Third, the valve grease, pay attention to the valve in the switch position. Ball valve maintenance are generally open position, under special circumstances choose to shut down maintenance. Other valves can not be the same place to open positions. The gate valve must be closed during maintenance to ensure that the grease fills the seal groove along the seal ring. If the seal is open, the seal grease will drop into the runner or valve chamber directly, resulting in waste. Fourth, the valve grease, often neglected grease problem. Fat injection operation pressure, fat injection, the switch position is normal. But in order to ensure that the valve grease, sometimes need to open or close the valve to check the lubrication effect, confirm the valve ball or gate surface lubrication uniform. Fifth, when fat, pay attention to the body of the sewage and plugging pressure relief problems. After the valve pressure test, the gas and moisture in the valve chamber of the seal chamber are increased due to the increase of the ambient temperature. When the grease is injected, blowdown and pressure relief should be carried out first in order to facilitate the smooth operation of the grease injection. After the fat seal air and moisture within the cavity is fully replaced. Timely discharge the valve cavity pressure, but also protect the safety of the valve. After the end of grease, be sure to tighten the drain and drain wire plug to prevent accidents. Sixth, note fat, pay attention to the issue of fat evenly. Normal injection, the grease hole from the nearest fat first grease, and then to the low point, the last is high, one after another fat. If you do not follow the law or not fat, that there is congestion, timely clearance. Seventh, also note the valve diameter and seal seat ring flush with the issue. For example, the ball valve, if there is an open position interference, you can adjust the open position limiter to confirm the diameter of the straight lock. Adjust the limit can not only pursue the open or closed position, to the overall consideration. If the opening flush, off is not in place, can cause the valve to be lax. Similarly, to adjust the position, but also consider opening the corresponding adjustment. Ensure that the valve's right-angle travel. Eighth, after fat, must seal good injection fat mouth. Avoid impurities to enter, or lipid-lipid injection at the mouth, cover to smear rust-proof, to avoid rust. In order to apply the next operation. Ninth, fat injection, but also to consider the specific issues in the future delivery of oil specific treatment. Given the different qualities of diesel and gasoline, the scouring and decomposition of gasoline should be considered. Valve operation in the future, encountered gasoline section operations, the timely replenishment of grease to prevent wear and tear occurs. Tenth, note fat, do not ignore the stem part of the grease. Valve shaft parts have sliding sleeve or packing, but also need to maintain the lubrication state, in order to reduce the frictional resistance during operation, such as can not ensure lubrication, the electric torque increases the wear parts, manual operation of the switch effort. Eleventh, some ball valve body marked with an arrow, if there is no English FIOW writing, the role of seal seat direction, not as a medium flow reference, the valve from the vent in the opposite direction. Normally, two-seated ball valves have bidirectional flow. Twelfth, valve maintenance, but also pay attention to electric head and its transmission mechanism in the water problem. Especially in the rainy season infiltration of rainwater. First, make the transmission mechanism or drive shaft rust, the second is the winter freeze. Caused by the electric valve operating torque is too large, damage to the transmission parts will make the motor no load or super torque protection jump can not be achieved by electric operation. Transmission parts damaged, manual operation can not be carried out. After the super-torque protection action, manual operation can not switch the same, such as forcing operation, will damage the internal alloy parts. In summary, the valve maintenance really treat with a scientific attitude, in order to make the valve maintenance work to achieve the desired effect and application purposes. Valve cleaning methods Valve casting is completed, the need for blast cleaning, there are generally two kinds of shot blasting machine more suitable, drum-type shot blasting machine and track-type shot blasting machine and hook-type shot blasting machine, the first two suitable for cleaning comparison Small valve, which is suitable for cleaning larger valves. Electric valve operation principle and maintenance Electric valve is usually connected by the electric actuator and the valve, after installation and commissioning become electric valve. Electric valve using electric energy as power to connect the electric actuator to drive the valve to achieve the valve switch, adjust the action. So as to achieve the pipeline medium switch or adjustment purposes. Solenoid valve is a type of electric valve; the magnetic field generated by the electromagnetic coil to pull the spool, thereby changing the valve body off, the coil power, spool relies on the pressure of the spring back.
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