Valve manufacturers: Tell you the technical requirements of valve procurement must be known

The specifications and categories of valves shall meet the requirements of the pipeline design documents

1. The valve model should be marked with the national standard number requirements. If it is an enterprise standard, the relevant description of the model should be indicated.

2. The working pressure of the valve must be ≥ the working pressure of the pipeline. The working pressure that the valve can withstand should be greater than the actual working pressure of the pipeline, and does not affect the price. When the valve is closed, any side of the valve should be able to withstand 1.1 times its working pressure, and the pressure value has no leakage; When the valve is opened, the valve body should be able to withstand twice the working pressure of the valve.

Second, choose the material of the valve

1. Valve material, since it is gradually not recommended to use gray cast iron pipe, the valve body should be made of ductile iron, and the grade of the casting and the actual physical and chemical test data should be marked.

2. Valve stem material, strive for stainless steel valve stem (2CR13), large diameter valve should also be stainless steel embedded valve stem.

3. The nut material is cast aluminum brass or cast aluminum bronze, and its hardness and strength are greater than the valve stem.

4. The valve stem bushing material should have a material not greater than the hardness and strength of the valve stem, and will not form electrochemical corrosion with the valve stem and valve body when submerged in water.

Valve manufacturer

Third, the operating mechanism of the valve

1. The direction of the valve switch should always be closed clockwise.

2. Because the valves in the pipe network are usually opened and closed manually, the number of revolutions opened and closed should not be too large, even for large diameter valves, it should be between 200-600 revolutions.

3. In order to facilitate the opening and closing operation of one person, the opening and closing torque should be 240m-m under pipeline pressure conditions.

4. The opening and closing end of the valve should be square tenon, standard size, and facing the ground so that people can operate the valve directly from the ground. Valves with roulette disks are not suitable for underground piping networks.

4. Packaging and transportation of valves

1. Lightweight baffles should be installed on both sides of the valve to achieve a firm seal.

2. Medium and small diameter valves should be tied together with straw ropes and transported in containers.

3. Large diameter valves are also packaged with simple wooden frame fixings to avoid damage during transportation.