Needle Valve is an adjustable valve, wider use, such as flame cutting with the cutting distance, adjust the flame temperature knob is needle valve. The instrument needle valve is an important part of the instrument measuring pipeline system. It mainly has globe valve and ball valve, and its function is to open or cut off the pipeline. Needle valve spool is a very sharp cone, like a needle into the valve seat, hence the name.
Globe Valve, also known as Globe Valve, is a forced sealing valve, so when the valve is closed, the pressure must be applied to the disc to force the sealing surface not to leak. When the medium from the bottom of the valve disc into the valve, the operating force to overcome the resistance is the friction of the stem and packing and the pressure generated by the medium thrust, closing the valve than open the valve force, so the diameter of the stem to be larger, otherwise there will be a valve stem top bending failure.
Installation Notes
1. Installation Location, height, inlet and outlet direction must meet the design requirements, note that the direction of media flow should be consistent with the direction of the Arrow valve body, the connection should be firm and tight.
2. The valve must be installed before the visual inspection, the valve nameplate should comply with the current national standards “General Valve Signs” GB 12220 provisions. For the working pressure of more than 1.0 MPa and the main pipe on the role of cutting off the valve, installation should be conducted before the strength and tightness performance test, qualified before the use. Strength Test, the test pressure is 1.5 times the nominal pressure, the duration of not less than 5 minutes, the valve shell, packing should be no leakage for qualified. In tightness test, the test pressure is 1.1 times of the nominal pressure, and the test duration meets the requirements of GB 50243.
Post time: Nov-25-2021