(1) Valves must be manufactured in accordance with the relevant technical standards, design drawings, technical documents and order contracts. They can only be shipped after passing the inspection.
(2) When there are special requirements, they should be specified in the order contract, and the inspection and supply should be in accordance with the specified requirements.
(3) The manufacturer should supply the products required by the user within the period specified in the contract.

Valves are important control devices in fluid pipeline systems. Their functions: connecting and cutting off media; preventing media backflow; regulating media pressure and flow; separating, mixing or distributing media; preventing media pressure from exceeding the specified value to ensure safe operation of pipelines or equipment.

In industrial pipeline systems and various civil pipeline facilities, valves play a vital role. They can control the flow, pressure and flow direction of fluids. The choice of valve connection method is directly related to the performance, reliability, installation convenience and subsequent maintenance cost of the entire pipeline system.

The requirements for valve sealing performance should be based on the prevention of leakage. Depending on the different parts and degrees of leakage, the leakage of the valve is different. Therefore, different anti-leakage measures need to be proposed.

Soft-seal elastic seat gate valve is mainly used in water supply and drainage systems. Temperature ≤80℃, nominal pressure ≤PN25, diameter ≤800mm. The valve body material is cast iron or ductile iron, cast steel or stainless steel. Standards adopted: CJ/T216-2013 Soft-seal Gate Valve for Water Supply and Drainage, GB/T 24924-2010 Elastic Sealed Gate Valve for Water Supply System. AWWA C509:2001.

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 is subject to relevant regulations. This regulation does not apply to the setting of valves on underground water supply and drainage pipelines.