Standard for plastic valves

Standard for raw material size of plastic valve:

The main types of plastic valves in the world are plastic ball valve, plastic butterfly valve, plastic check valve, plastic diaphragm valve and plastic stop valve. The main structural forms are two-way, plastic three-way and multi-way valves. The raw materials are ABS, PVC-U, PVC-C, Pb, PE, PP and PVDF. In the international standard of plastic valve products, the first is to require the raw materials used in the production of valves. The manufacturer of the raw materials must have a creep failure curve that conforms to the product standard of plastic pipes. At the same time, the sealing test, valve body test, long-term performance test, fatigue strength test and operating torque of plastic valves are specified

Plastic valves shall meet the following standards:

1. Requirements for raw materials: the materials of valve body, bonnet and bonnet shall be in accordance with iso15493:2003 specification for industrial plastic piping systems - ABS, PVC-U and PVC-C - pipe and fitting systems - Part 1: Metric series and iso15494:2003 specification for industrial plastic piping systems - Pb, PE and PP - pipe and fitting systems - Part 1: Metric series.

2. Design requirements: if the valve has only one pressure bearing direction, it shall be marked with arrows outside the valve body, and the valve of symmetrical design shall be suitable for two-way flow and isolation of fluid. The sealing part is driven by the valve stem to open and close the valve. It shall be positioned at the end point or any position in the middle by the friction force or the actuator. The fluid pressure shall not change its position.

The minimum through hole of plastic valve shall meet the following standards:

1. For any pore diameter of medium flow on the valve, it shall not be less than 90% of the valve DN value;

2. For the valve whose structure needs to reduce the medium flow hole diameter, the manufacturer shall indicate the actual minimum through hole.

3. The seal between valve rod and valve body shall conform to en736-3.

4. In terms of valve wear resistance, the service life of worn parts shall be considered in the design of the valve, or the manufacturer shall indicate the suggestion of replacing the whole valve in the operation instruction.

5. All valve operators shall be suitable for a flow rate of 3 M / s.

6. From the top of the valve, the handle or hand wheel of the valve shall close the valve clockwise.

Due to the advantages of plastic valve, such as light weight, corrosion resistance, non adsorption of scale, integrated connection with plastic pipeline and long service life, the application advantages of plastic valve in the plastic pipeline system of water supply (especially hot water and heating) and other industrial fluids are incomparable with other valves.