The selection of welding wire material is mainly based on the valve body material. For common valve body materials, carbon steel welding wire such as H08MnA and low alloy steel welding wire such as H10Mn2 are usually selected as welding wire materials. At the same time, the selection of welding wire diameter also has a great impact on the weld shape. When the welding current, arc voltage and welding speed are fixed, the weld penetration is inversely proportional to the welding wire diameter, and the weld width is proportional to the welding wire diameter. For the submerged arc automatic welding commonly used for all welded pneumatic ball valves, the welding wire diameter is generally 2.5~6mm.

(3) Manual valve: manual valve is operated manually by means of hand wheel, handle, lever and sprocket. When the opening and closing torque of the valve is large, this wheel or worm gear reducer can be set between the hand wheel and the valve stem. If necessary, the universal joint and transmission shaft can also be used for remote operation.