Double Disc gate valve Stainless Casting Steel GOST Flanged Gate Valve China factory with high quality
What is the Double Disc Gate Valve?
The advantages of the Double Disc Gate Valve versus the traditional wedge type product are:
- The discs of parallel slide gate valve will never block in closed position,while it may occur with a wedge type that has been closed with the line in temperature and opened when the line is cold.
- The opening/closing torque of parallel slide gate valve is much lower than a corresponding gate valve wedge type valve,resulting in smaller actuator and less expensive actuation systems.
- The “sliding” feature keeps dirt away from the sealing surfaces.
Sealing mechanism of the Double Disc Gate Valve.
- When the pipe pressure or pressure difference of two sides is small,the compressed spring will push the discs to the sealing rings,it’s the initial sealing of the parallel slide gate valves under low pressure conditions.
- When the pipeline pressure increase,the increasing line pressure will push the disc against the seat ring with force in the low pressure side,which creates the secondary seal. The higher the medium pressure,the better the sealing performance
Therefore this valve type is widely used in high pressure and high temperature services such as steam and feedwater.
Main features of NORTECH Double Disc Gate Valve
Double Disc Gate Valve Design Features
- Tight shut off achieved by line pressure— not from mechanical wedging action therefore eliminating thermal binding
- Minimum pressure drop
- Bypass arrangement available
- Available in high temperature carbon steel, chrome-moly steel, and stainless steel materials of contruction: ASTM A216 GR WCB, ASTM A217 GR WC6, ASTM A217 GR, WC9, and ASTM A351 GR CF8M.
- Available with manual operator, or fitted with suitable actuator of choice
|Product name||Double Disc Gate Valve|
|Pressure rating||PN16/25/40/63/100/250/320,Class 150/300/600/900/1500/2500|
|Design standard||ASMEB16.34,API 6D|
|Working temperature||-29~425°C (depending on materials chosed)|
|Type of operation||Handwheel/Manual gearbox/Electric actuator|
Disc and Spring of the Double Disc Gate Valve
:compressed spring in inconel X750 is placed between two discs in parallel position.
Pillar and Bridge BBOSY of the Double Disc Gate Valve
:Pillar & bride BBOSY design,the York is designed with 2 or 4 forged steel pillars,depending on the valve diameter.
Hydraulic test of NORTECH Double Disc Gate Valve
Inspection of Double Disc Gate Valve
- shell test 1.5 times of rated pressure
- low pressure seal test with air 0.6 Mpa
- high pressure seal test 1.1 times of rated pressure
Where is the Double Disc Gate Valve used for ?
Double Disc Gate Valve is widely used in the field chemical,petroleum, natural gas,oil and natural gas production wellhead device, conveying and storage pipelines (Class150~2500/PN1.0~42.0MPa, operating temperature -29~450℃),pipes with suspended particle media,urban gas pipeline,water engineering.it's designed to provide isolation and transmission of flow in a piping system or a component when closed, sometimes can be installed in the pump outlet for regulating or control of flow.