Maintenance of Valve Grease Injection

◆ When the valve grease is injected, the problem of the amount of grease is often ignored. After the grease gun is refueled, the operator selects the valve and the grease injection connection mode, and carries out the grease injection operation. There are two situations: on the one hand, the amount of fat injection is small, and the sealing surface is accelerated by the lack of lubricant. On the other hand, excessive fat injection causes waste. There is no precise calculation of the sealing capacity of different valves according to the valve type category. The sealing capacity can be calculated according to the valve size and category, and then the appropriate amount of grease can be injected reasonably.

◆ When valve grease is injected, the pressure problem is often ignored. During the operation of grease injection, the pressure of grease injection changes regularly with peaks and valleys. If the pressure is too low, the seal leaks or fails, if the pressure is too high, the grease injection port is blocked, the grease in the seal is hardened, or the sealing ring is locked with the valve ball or valve plate. Usually when the grease injection pressure is too low, the injected grease flows into the bottom of the valve chamber, which generally occurs in small gate valves. The grease injection pressure is too high, on the one hand, check the grease injection nozzle, if the fat hole is blocked, replace it. On the other hand is the hardening of grease, to use a cleaning solution, repeatedly soften the failed sealing grease, and inject new grease replacement. In addition, the sealing model and sealing material, also affect the injection pressure, different sealing forms have different injection pressure, in general, the hard seal injection pressure is higher than the soft seal.

◆ When the valve grease is injected, pay attention to the valve in the switch position. Ball valve maintenance is generally in the open state, in special cases choose to close maintenance. Other valves can not be treated in the open position. The gate valve must be in the closed state during maintenance to ensure that the grease is filled with the sealing groove along the sealing ring. If it is opened, the sealing grease will fall directly into the runner or valve chamber, resulting in waste.

◆ Valve grease injection, often ignore the grease injection effect. In the grease injection operation, the pressure, the amount of grease injection and the switch position are normal. However, in order to ensure the valve grease effect, it is sometimes necessary to open or close the valve, check the lubrication effect, and confirm that the valve ball or gate surface is evenly lubricated.

◆ When filling grease, pay attention to the problem of valve body blowdown and wire plug pressure relief. After the valve pressure test, the gas and water in the valve chamber will increase the pressure due to the increase of the ambient temperature, and the pressure relief should be carried out before the grease injection, so as to facilitate the smooth progress of the grease injection. After grease injection, the air and water in the sealing cavity are fully replaced. Timely release of valve chamber pressure, but also to ensure the safety of valve use. After the grease injection, be sure to tighten the drain and pressure relief wire plug to prevent accidents.

◆ When injecting fat, pay attention to the problem of uniform fat. In normal grease injection, the nearest grease injection hole is the first grease, then the low point, and finally the high point, and the grease is pumped out one by one. If it is not according to the law or does not produce fat, it proves that there is blockage, and it is cleared in time.

◆ Grease injection should also observe the valve diameter and sealing ring seat flush problem. For example, a ball valve, if there is an open position interference, you can adjust the open position stopper inward to confirm that the diameter is straight and locked. Adjusting the limit can not only pursue the position of the open or close side, but also consider the whole. If the opening position is even and the closing is not in place, the valve will be loosely closed. Similarly, the adjustment is in place, and the corresponding adjustment of the opening position should also be considered. Make sure the valve is at right angles.

◆ After grease injection, be sure to seal the grease injection mouth. Avoid impurities entering, or lipid oxidation at the grease injection mouth, and apply anti-rust grease to the cover to avoid rust. So that it can be applied in the next operation.

◆ When filling grease, it is also necessary to consider the specific treatment of specific problems in the future oil sequential transportation. In view of the different qualities of diesel and gasoline, the erosion and decomposition capacity of gasoline should be considered. In the future valve operation, when encountering the gasoline section operation, timely add grease to prevent wear.

◆ Grease injection, do not ignore the grease injection of the valve stem. The valve shaft part has a sliding sleeve or packing, which also needs to be kept lubricated to reduce the friction resistance during operation. If lubrication cannot be ensured, the torque during electric operation increases the wear parts, and the switch is laborious during manual operation.

◆ Some ball valve body marked with arrows, if there is no English FLOW writing, it is the direction of the seal seat, not as a reference to the medium flow direction, the valve self-discharge direction is opposite. Normally, the two-seat sealed ball valve has a two-way flow direction.

◆ When maintaining the valve, it is also necessary to pay attention to the water problem in the electric head and its transmission mechanism. Rainwater seeps in especially during the rainy season. One is to rust the transmission mechanism or the transmission shaft sleeve, and the other is to freeze in winter. Resulting in excessive torque during the operation of the electric valve, damage to the transmission components will make the motor no-load or over-torque protection jump can not achieve electric operation. The transmission component is damaged and manual operation is not possible. After the super torque protection action, manual operation can not be switched, such as forced operation, will damage the internal alloy parts of the valve maintenance to be treated with a scientific attitude, in order to make the valve maintenance work to achieve the desired effect and application purposes. In order to make the production normal operation, reduce parking, increase economic benefits, in the valve aspect, we must do these three points:

1. First, the correct selection of valves is the foundation.
   
2. Second, the correct use of valves is the most critical.
   
3. Third, correct maintenance is the guarantee.