Is the arrow on the low temperature gate valve body the direction of pressure relief? Does the arrow point to the pressure relief hole? The pressure relief hole is installed at the inlet (high pressure side), what will happen if it is installed backwards?

The low-temperature medium will gasify and expand under the condition of heating up. If the boosting medium in the valve cavity cannot be safely discharged, it will cause the danger of overpressure. The pressure relief hole is set up to prevent the pressure in the middle cavity of the gate valve from rising abnormally. The pressure relief hole is at the inlet end of the medium, which is determined by the sealing characteristics of the gate valve. If it is installed backwards, it will affect the sealing performance of the valve, and the safety will not be affected.

The arrow direction of the low temperature gate valve indicates the installation direction of the valve, which is related to the pressure relief hole. The opposite direction of the arrow is the side of the pressure relief hole. The pressure relief hole is installed on the high pressure side of the valve. That is to say, in a low temperature system, when the gate valve is closed, the arrow points to the low pressure side, not the flow direction of the medium.