This regulation applies to the setting of gate valves, stop valves, ball valves, butterfly valves and pressure reducing valves in petrochemical plants. The setting of check valves, safety valves, regulating valves and steam traps shall refer to the relevant regulations. This regulation does not apply to the setting of valves on underground water supply and drainage pipes.

Model and specification verification
Confirm that the type of check valve (such as lift type, swing type, butterfly type, etc.), nominal diameter, pressure level and pipeline system match to avoid leakage or failure due to specification mismatch.

Abnormal pressure rise in gate valve cavity refers to a phenomenon in which, when the valve is closed or partially closed, the trapped medium expands due to heat or pressure buildup, causing the pressure in the valve cavity to rise significantly, potentially exceeding the system design pressure. This situation can pose serious safety hazards and equipment damage, requiring targeted protective measures.

Excessive pursuit of high material: non-corrosive media (such as water, air) can use carbon steel valve body to avoid unnecessary costs.
Ignore dynamic seals: Valves that are frequently operated need to pay attention to stem seals (such as graphite packing vs. spring-loaded PTFE).
Ignore thermal expansion: High-temperature pipelines need to calculate the thermal displacement of the valve body and pipeline to prevent stress damage.

1. Selection principles. 2. Recommended material types. 3. Typical application cases.

【Valve Knowledge】Valve Performance Inspection