Precautions for valve products at work

 

The valve is an important component in the thermal system. The operator often has to deal with the valve. Therefore, the structure and performance of the valve must be familiar and mastered. The valve direction, opening degree mark and indication signal should be correctly identified. The valve should be skillfully and accurately adjusted and operated. Handle various emergency faults in a timely and decisive manner. Pay attention to the following categories when operating:

1. Identify the switch direction of the valve. Generally, the manual valve, the clockwise direction of the handwheel indicates the closing direction of the valve, and the counterclockwise direction indicates the opening direction of the valve. The direction of the individual valves is opposite to the above-mentioned opening and closing. Before the operation, the opening and closing signs should be checked before operation. The top surface of the plug valve stem The groove is parallel to the channel, indicating that the valve is in the fully open position. When the valve stem is rotated by 90°, the groove is perpendicular to the channel, indicating that the valve is in the fully closed position, and some of the plug valves are opened in parallel with the wrench and vertically closed. The valve operation of the three-way and four-way should be carried out according to the marking of opening and closing the reversing direction.

2. Use force to be appropriate. When operating the valve, the force is too strong and too easy to damage the handle, hand wheel, scratch the valve stem and sealing surface, or even crush the sealing surface. Do not use a large wrench to open and close the small valve to prevent excessive force. Large, damaged valve.

3. Before opening the steam valve, the pipe must be preheated to remove the condensed water. When opening, it should be slowly opened to avoid water hammer and damage the valve and equipment.

The larger diameter valve is provided with a bypass valve. When opening, the bypass valve should be opened first. After the pressure difference between the two sides of the valve is reduced, the large valve is opened. When closing, first close the bypass valve and then close the large valve.

The valve of the gate valve and the shut-off valve is opened to the head, and it is necessary to rotate 1/4 - 1/2 turn, which is beneficial to the operation check, so as to avoid over-tightening and damage the valve.