◆ When the valve is greased, 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 method to perform the grease filling operation. There are two cases: on the one hand, the amount of grease is less than that of the grease, and the sealing surface is accelerated by the lack of lubricant. On the other hand, excessive fat injection causes waste. There is no accurate calculation of the different valve sealing capacities based on the valve type category. The sealing capacity can be calculated in terms of valve size and type, and a proper amount of grease can be injected reasonably.

◆ When the valve is greased, the pressure problem is often ignored. During the grease injection operation, the grease injection pressure changes regularly in the 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 seal grease hardens or the seal ring and the valve ball and the valve plate are locked. Usually, when the grease pressure is too low, the injected grease flows into the bottom of the valve cavity, which usually occurs in a small gate valve. On the one hand, the grease injection pressure is too high. On the one hand, the grease injection nozzle is checked. If the grease hole is blocked, the situation is replaced. On the other hand, the grease is hardened. The cleaning solution is used to repeatedly soften the failed sealing grease and inject a new grease. . In addition, the sealing type and sealing material also affect the grease filling pressure. Different sealing forms have different grease filling pressures. Generally, the hard sealing grease pressure is higher than the soft sealing.

◆ When filling the valve, pay attention to the problem that the valve is in the switch position. The ball valve is normally in the open position during maintenance and maintenance. In special cases, the maintenance is turned off. Other valves cannot be discussed in terms of opening. The gate valve must be closed when it is being maintained, ensuring that the grease fills the sealing groove along the sealing ring. If it is opened, the sealing grease will fall directly into the flow channel or valve cavity, resulting in waste.

◆ When the valve is greased, the problem of grease injection is often ignored. The pressure, grease injection amount and switch position are normal during the grease filling operation. However, in order to ensure the grease filling effect of the valve, it is sometimes necessary to open or close the valve to check the lubrication effect and confirm that the valve ball or the surface of the valve is evenly lubricated.

◆ When filling grease, pay attention to the problem of valve body discharge and wire plug pressure relief. After the valve pressure test, the gas and moisture in the valve chamber of the sealed chamber are boosted due to the increase of the ambient temperature. When the grease is injected, the drain and pressure should be drained first, so as to facilitate the smooth operation of the grease injection work. After the grease is applied, the air and moisture in the sealed chamber are sufficiently replaced. Timely discharge of the valve cavity pressure also ensures the safety of the valve. After the grease is applied, be sure to tighten the drain and pressure relief plug to prevent accidents.

◆ When filling grease, pay attention to the problem of uniform grease. In normal fat injection, the fat-producing hole closest to the grease injection port first comes out of fat, then to the low point, and finally to the high point, and the fat is successively produced. If it is not in accordance with the law or does not produce fat, it proves that there is blockage and timely clearing

◆ When filling grease, also observe the problem that the valve diameter is flush with the seal seat. For example, if there is a ball valve, if there is open position, you can adjust the opening limiter to the inside to confirm that the hole is straight and locked. Adjusting the limit can not only pursue the opening or closing of a position, but should be considered as a whole. If the opening position is flush and not closed, the valve will not be closed. In the same way, if the adjustment is in place, the corresponding adjustments should also be considered. Ensure the right angle of the valve

◆ After filling the grease, the grease injection port must be sealed. Avoid the entry of impurities, or the oxidation of grease at the grease injection port. Apply anti-rust grease to the cover to avoid rust. For the next application

◆ When filling grease, it is also necessary to consider specific issues in the future delivery of oil products. In view of the different qualities of diesel and gasoline, the ability to flush and decompose gasoline should be considered. In the future operation of the valve, when encountering the gasoline section, timely replenish the grease to prevent wear and tear.

◆ When filling grease, do not ignore the grease filling on the stem. There is a sliding bushing or packing on the valve shaft, and it is also necessary to maintain the lubrication state to reduce the frictional resistance during operation. If the lubrication cannot be ensured, the torque is increased during the electric operation, and the switch is laborious during manual operation.

◆ Some ball valve bodies are marked with arrows. If there is no English FIOW handwriting, it is the direction of action of the sealing seat. It is not used as a reference for medium flow, and the valve is in the opposite direction. Normally, the two-seat sealed ball valve has a two-way flow direction

◆ When maintaining the valve, pay attention to the water inlet problem in the motorized head and its transmission mechanism. Especially the rain that infiltrates during the rainy season. One is to rust the transmission mechanism or the transmission bushing, and the other is to freeze in winter. The torque caused by the operation of the electric valve is too large. Damage to the transmission parts may cause the motor to be unloaded or the over-torque protection may not be electrically operated. The drive components are damaged and cannot be performed manually. After the over-torque protection action, the manual operation can also not be switched. For example, if the operation is forcibly, the internal alloy parts will be damaged. The valve maintenance should be treated scientifically, so that the valve maintenance work can achieve the desired effect and application purpose. In order to make production run normally, reduce parking and increase economic efficiency, in the aspect of valves, we must do a good job of these three points. The correct choice of valves is the basis. The most important thing is to use valves correctly. 3. Correct maintenance is the guarantee.