The Function And Selection Of Common Needle Valve
The Function and Selection of Common Needle Valve.
(A) the role of needle: needle valve in the tank when the pressure exceeds the working pressure, that is automatically open, release the tank gas to prevent damage to the tank or an explosion to ensure the safe operation of equipment.
(B) the selection of needle: needle valve types are mainly spring and lever type two. Spring-type needle valve is divided into two kinds of exterior and built-in. Tank needle valve with an external spring, slotted needle valve should be equipped with spring. As the spring-type needle valve is versatile, simple structure, small size, weight, maintenance and disassembly test are more convenient, so the use of more common. Needle valve is divided into micro-Kai and full Kai two. Micro Kai and Quan Kai refers to the opening height of the valve. Spring-type needle valve, there are closed and not closed two. Closed that the exclusion of the gas is not leaked, all along the export of the discharge tube to the designated place. Because liquefied petroleum gas is flammable, explosive materials, do not allow casual leakage in the air, so the storage equipment should use closed closed spring valve. The needle valve produced by the factory is attached with a nameplate, and the exhaust capacity specified on the nameplate is greater than or equal to the maximum displacement of the tank. Domestic models for the A42Y-16C, A44Y-16C and A42F-16C and so on.
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.
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: PN2.5PN4PN6.4PN16PN32Mpa 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 and so on.