Should valves be subject to supervision and inspection?
Thread Content
Dear experts, may I ask whether supervision and inspection are required for the valves? Which standard and which clause is the basis for this? Thank you.
Whether a valve requires supervised inspection depends on its area of use and pressure rating. In accordance with the Special Equipment Safety Law and the Regulations on the Supervision of Special Equipment Safety, valves used in pressure pipelines fall under the category of pipeline components for special equipment; if the operating pressure is 1.0 MPa or higher and the diameter is 25 mm or greater, supervision inspections are required. The specific basis is Article 16 of the Regulations on the Safety Management of Pressure Pipelines. .
Valves are standardized products; generally, no supervision inspection is carried out, only FAT is performed. Perhaps nuclear power valves require supervision during manufacturing.
“Should valves be subject to supervision and inspection? ”It is recommended to clearly specify at which stage the supervision and inspection will take place, such as the leak testing, pressure testing, degreasing, and other procedures required before installation. Because for some devices, after installation it is necessary to ensure that the conditions required for using the valves are met, and supervision and inspection are required for reference.
The importance of supervision and inspection: As a key component of piping systems, the quality of valves directly affects the safe and stable operation of the entire piping system. Therefore, it is highly necessary to conduct supervised inspections on valves. Standard reference: API Std 598-1996 \"Specifications for Inspection and Testing of Valves\" is a commonly used standard for the inspection and testing of valves. This standard applies to the requirements for the inspection, testing, re-inspection, and pressure testing of valves such as gate valves, globe valves, plug valves, ball valves, check valves, and butterfly valves. These requirements include housing testing, upper seal testing, low-pressure seal testing, high-pressure seal testing, and visual inspection of the castings. The Regulations on the Safety Supervision of Special Equipment (State Council Order No. 373) also stipulate that entities using special equipment shall regularly calibrate, maintain, and inspect the safety accessories, safety protection devices, measurement and control devices, as well as related auxiliary instruments and meters of such equipment, and keep records of these activities. As a safety accessory for special equipment, a safety valve must also undergo pressure testing before it can be used, and it must be calibrated by units (departments, personnel) authorized by the safety supervision and management department. Contents of supervision inspection: After the valve is manufactured, inspection of the product before it leaves the factory is essential and crucial. This includes visual quality inspection and geometric dimension inspection, measuring the visual quality and connection dimensions of the valve, checking whether the thickness of the valve body and valve cover meets the requirements of the design drawings, as well as verifying the site for hydrostatic or pneumatic testing of the housing. Manufacturing enterprises should provide inspection officers with a copy of the manufacturing license to facilitate more effective supervision and inspection of valves. For manufacturing enterprises of relatively small scale and those that have not produced products under high temperature and high pressure for some time, it is recommended to submit production plans to the inspection department on a monthly basis. In summary, valves require supervised inspection, and the relevant guidelines for this include API Std 598-1996 \"Rules for Inspection and Testing of Valves\" as well as regulations such as the \"Regulations on the Safety Supervision of Special Equipment\".
Imported valves must undergo arrival inspection, or safety performance testing, as of June 1 this year. Domestically produced valves that are manufactured as standard components do not require supervision and inspection, as they fall outside the scope of the supervision and inspection for special equipment (TSG D7006).