Applicable principle of model selection
1, oil and gas transmission line, need cleaning of pipeline buried in the ground and the choice of sizes, and the needle valve is welded structure, Embedded on the earth, choose full-bore welding connection or flange connection of valve.
2 and oil pipes and storage equipment, choose the needle valve flange connection.
3, city gas pipeline and gas, flange and threaded connections needle valve type.
4, metallurgical oxygen pipeline system, appropriate chooses through strict defatted processing, the needle valve flange.
5, low temperature medium pipeline system and devices, appropriate chooses plus bonnet low-temperature needle valve.
6 and refining of catalytic cracking unit on the pipeline system, can choose the needle valve lift lever type.
7 and chemical corrosive medium ph system as the device and pipe system, appropriate chooses austenitic stainless steel manufacturing, ptfe seat sealing for the stainless steel needle valve.
8, metallurgical, power system, petrochemical equipment, the high temperature medium urban heating system of pipeline system or device, can choose the metal to metal seal needle valve.
9 and when to flow, can choose the worm gear and worm drive, pneumatic or electric V belt of regulating valve opening needle.
As for the following requirements or otherwise, shall be changed in order to illustrate the contract:
1 the valve specifications (pounds of valve with an inch level; metric valve with millimeter)
2 stress level or nominal pressure
3 flange size and form
4 the welding and aperture
5 socket and threaded end size
6 structural length
7. Refractory, anti-static devices
8. To worm gear or pneumatic, electric
9 to lock structure, to no match locked
The materials (including subject, the stem, fasteners, etc.)
11. Gaskets
12. The packing
Sealing material matching (13) sealing ball valve and sealing)
14 other
