网络优化资料：

Material of valve parts.

(a) Specify the material markings of the valve body, bonnet, cover plate, end flange and weld end and the material standards and specifications to be followed;

(b) Requirements for the material of the valve cover and cover plate;

(c) Non-metallic parts and material specifications for parts;

(d) Other component materials, such as brackets, bracket nuts, valve stems, gates, spheres, plugs, discs, handwheels, transmissions, pipe plugs, electric accessories, etc. shall be subject to standard specifications;

(e) Material requirements for anti-sulfide stress fracture components;

The performance requirements of alternative metal materials, and the definition and judgment of the composition of the vacuum solenoid valve.

The welder specifications have clear requirements for pressure parts, pressure control parts, welders and repair welding, and the water pump solenoid valve has clear requirements for welder performance inspection and test items.

Type and type of valve

(Requires the form, sealing structure and operating actions of gate valves, plug valves, ball valves, check valves and other closing parts);

(a) It specifies the gate form of the double gate valve and the flat gate valve, the auxiliary seal of the gate valve stem and the upper seal seat;

(b) It specifies the composition and rotation form of the plug valve sealing pair;

(c) It specifies the composition and rotation mode of the ball valve sealing pair;

(d) It specifies the composition and medium flow capacity of the sealing pair of various check valves (swing check valve, single flap and double flap).

Valve type (minimum diameter and allowable deviation of full-way valve, valve structure length).