Description

Product overview

Chief structure features and usages
1. The main body of this series valve uses a casting and forging structure and has a dual-direction seal of parallel secondary semi-forced dual-sealing and the motions of both the sealing face to its due position and the tapered block to wedge-up are separated to have zero lead age come true.

2. The sealing face is of a small frictional force if motion,lightly opened and closed and has a self compensation function for wearing.

3. Simple structure easy to more than *0 years of long duration.

4. A vacuum sealing structure is set in the filling chamber on the valve cover,which has the action of self-expanding and impacting,the joint faces are sealing with the expansive material of high strength to completely isolate the system from air.

5. Two connection ways of b flange and welding,two ways to drive of heand-and eletric-operation. The valve can be used as the open & close device for the pipelines under the working temperature Less than**5degree centigrade and **0 degree centigrade  and the working medium of water,steam or air;especially suitable to act as the vacuum isolating sealing for the system of steam turbine's considernation and vacuum negative pressure in steam power plants.

Valve ctrucure type:

Mode1 NKJ*1 Vacuum isolating stop valve;Model NKZ*4 and NKZ*4 Vacuum isolating gate valves.

Manufacture and acceptance standard:

1. Manufacture,acceptance and technical conditions per GB/T****4,GB/T****5.

2. Face-to face dimensions per GB/T****1.

3. Flange sizes per JB/T****9,GB/T********4.

Material for main parts

Body,Bonnet: *5 or WCB

Valve stem：Cr.stainless steel，*5Cr2MoV

Disc：Cr.stainless steel，*2Cr1MoVA。

Sealing face：H: alloy steel，Y: carbide alloy

Yoke nut：Al bronze

Packing：Expanding compound graphite

Fastener：High-grade carbon steel，Cr.Mo steel