Welded vacuum stop valve
I. Introduction:
The main body of the vacuum welding gate valve adopts a cast-forged structure, featuring a parallel double-seat half-forced bidirectional sealing design. The sealing surface positioning movement and wedge block tightening movement act in separate steps to achieve zero leakage. The friction coefficient between sealing surfaces is small, making opening and closing convenient. Moreover, the wear of sealing surfaces has an automatic compensation function. The vacuum gate valve has a simple and compact structure, easy maintenance, and a long service life. The valve cover packing chamber is equipped with a vacuum sealing structure, which has a self-expansion and pressing effect. In addition, each connection surface is sealed with high-strength expansion material, isolating the system from the atmosphere and providing excellent vacuum sealing performance. This series of valves has two connection forms: flange connection and welding connection, and two driving modes: manual and electric.This series of vacuum welding gate valves is suitable for pipelines with working temperatures ≤425℃ and ≤550℃, and working mediums of water, air, and steam, serving as an opening and closing device. It is especially applicable to steam turbine condensation and vacuum negative pressure systems in thermal power plants, playing a role in vacuum sealing isolation.
II. Main Structural Features and Uses:
1. The main body adopts a cast-forged structure, with parallel double-seat half-forced bidirectional sealing. The sealing positioning movement and wedge block tightening movement act in separate steps to achieve zero leakage.
2. The vacuum gate valve has small friction force on the sealing surface, making opening and closing light and convenient. Moreover, the wear of sealing surfaces has an automatic compensation function.
3. The vacuum gate valve has a simple and compact structure, easy maintenance, and a long service life.
4. The valve cover packing chamber is equipped with a vacuum sealing structure, which has a self-expansion and pressing effect. In addition, the sealing uses high-strength expansion material, completely isolating the system from the atmosphere and providing excellent system air tightness.
5. The vacuum gate valve has two connection forms: flange connection and welding connection, and two driving modes: manual and electric.
This valve is suitable for pipelines with working temperatures ≤425℃ and ≤550℃, and working mediums of water, steam or air, serving as an opening and closing device. It is especially applicable to steam turbine condensation and vacuum negative pressure systems in thermal power plants, playing a role in vacuum isolation and sealing.
III. Performance Specifications:
Product type | Shell strength test/MPa | Upper seal test/MPa | Seal test/MPa | Applicable medium | Applicable temperature/℃ |
NKJ61H-40 | 6.0 | 4.4 | 4.4 | Water, Steam, Air | ≤425 |
NKJ61H-64 | 9.6 | 7.0 | 7.0 | ||
NKJ61H-100 | 15.0 | 11.0 | 11.0 | ||
NKJ61Y-40I | 6.0 | 4.4 | 4.4 | Water, Steam, Air | ≤550 |
NKJ61Y-64I | 9.6 | 7.0 | 7.0 | ||
NKJ61Y-100I | 15.0 | 11.0 | 11.0 |
IV. Parts Materials:
Part name | Valve body, Bonnet | Valve Stem | Disc | Sealing face | Valve stem nut | Packing | Fastener |
NKJ61H-C Type | 25 or WCB | Chrome stainless steel | Chrome stainless steel | H: Alloy steel | Aluminum bronze | Expanding compound graphite | High-grade carbon steel |
NKJ61Y-I Type | Cr.Mo steel | 20Cr1Mo1VA or 38CrMoAlA | 12Cr1Mo1VA | Y: Carbide alloy | Cr.Mo steel |
V. External Dimensions:
Nominal diameter DN/mm | Nominal pressure PN/MPa | Main external and connecting dimensions/mm | |||||||
L | H | D | D0 | D1 | L1 | α | W | ||
10 | 4.0 | 130 | 245 | 36 | 11 | 18.4 | 10 | - | 120 |
15 | 130 | 245 | 36 | 16 | 22.5 | 10 | - | 120 | |
20 | 150 | 265 | 44 | 21 | 28.5 | 11 | - | 160 | |
25 | 160 | 270 | 48 | 26 | 34.5 | 12 | - | 200 | |
32 | 180 | 285 | 48 | 34 | - | - | 37°30' | 240 | |
50 | 230 | 365 | 64 | 48 | - | - | 37°30' | 300 | |
80 | 310 | 430 | 95 | 78 | - | - | 37°30' | 350 | |
125 | 400 | 500 | 143 | 126 | - | - | 37°30' | 400 | |
| Machinery & Equipment/Valves/Globe Valves | |
