Needle Valve Needle valve is a precise adjustment of the valve, the use of a wide range, such as flame cutting with the cut, adjust the flame temperature knob is the needle valve. Instrument needle valve is an important part of the instrument measuring pipeline system, mainly with cut-off valve and ball valve, its function is to open or cut off the pipeline path. Needle valve spool is a very sharp cone, as if the needle into the valve seat, hence the name.
Needle Valve Any valve is used to cut off the fluid. According to the different spool, can be divided into cut-off valve, gate valve, plug valve, ball valve, butterfly valve, needle valve and so on.
Needle valve is resistant to greater pressure and better sealing performance than other types of valves. It is generally used for small flow, higher pressure gas or liquid media seals. Needle valve is used in conjunction with pressure gauges The general needle - shaped valve shape is made of threaded connection. Nominal pressure: PN5.5 PN4 PN6.4 PN16 PN32Mpa Nominal diameter: DN5 ~ DN25 Applicable medium: oil, water, gas and other non-corrosive or corrosive medium Applicable temperature: -20 ℃ ~ +404 ℃ -70 ℃ ~ -240 ℃ ≤540 ℃ ≤570 ℃ and other manufacturing materials: 20 # ﹑ 1Cr18Ni9Ti ﹑ 304, 316, 316L ﹑ 12Cr1Mov, etc.
1),Needle Valve installation location, height, import and export direction must meet the design requirements, pay attention to the direction of media flow should be consistent with the direction of the valve body arrow, the connection should be firmly close.
2), the valve must be installed before the appearance of inspection, the valve nameplate should be consistent with the existing national standard "common valve mark" GB 12220 requirements. For working pressure greater than 1.0 MPa and in the trunk pipe to play a role in the disconnection of the valve, the installation should be carried out before the strength and rigidity of the test, qualified after quasi-use. Strength test, the test pressure of 1.5 times the nominal pressure, the duration of not less than 5min, the valve shell, the filler should be no leakage for the qualified. Tightness test, the test pressure is 1.1 times the nominal pressure; test duration in line with GB 50243 requirements.
