一级标题
一级标题
1、General
The instruction includes globe valves’ installation, maintenance and usage.
1.1 Warning
Safety first.
Pls make below questions clear before removing the globe valve from pipe lines for your safety.
1. What is the pipe medium?
Make sure what the medium is. Pls clarify to the relevant department if any questions.
2. Do you take protection and precautionary measures?
Pls wear protective closing and equipment for preventing special medium from damage.
3. Is the pipe line closed or the pipe pressure reduced?
Pls close the pipe line, reduce the pressure and drain pipe medium out.
4. Is the globe valve closed?
Pls make sure that the globe valve is closed before removing, installing and using.
2 Globe valve description and specification.
2.1、Description
Globe valve is closed and open through disc moving along seat center line. Change of seat hole has a direct ratio relation with disc moving distance. In addition, short off-on stem distance and reliable cut off function, it is suitable to adjust flow. So this kind of valve is suitable to be used in cutting off and adjusting flow.
（1）Advantage：
1. Globe valve is wear resisting between disc and body due to less friction than gate valve in progress of off and on. 2. The open distance is jut 1/4 seat channel distance, shorter than gate valve. 3. It’s convenient to maintain due to only one sealing face between body and disc. 4. Valves have high temperature resistance due to stuffing mixed both asbestos and graphite, usually used as steam valve.
（2）Disadvantage:
1. The minimum flow resistance of globe valve is higher than other similar valves due to medium flow direction through the valve changed. 2. It is slower than ball valves when opening globe valves due to longer distance.
（3）Application: Chemical, petroleum, metallurgy, papermaking, pharmaceutical and etc.
2.2 Performance specification
Performance specification | ||||||
Pressure Rating (lb) | □150Lb □300Lb □400Lb □600Lb □800Lb □900Lb □1500 □2500Lb □other | |||||
Size (inch) | 2—42 | |||||
Application Medium | □no corrosion □corrosion □other | |||||
Application Temperature(℃) | □-29~120 □-29~535 □-46~345 □-29~425 □-196~600 □other | |||||
Test and work pressure(Mpa) | Shell test | 1.5 | Test medium | water | Test temperature | normal temperature |
Sealing test | 1.1 | water | ||||
Back sealing test | 1.1 | water | ||||
low pressure sealing | 0.6 | gas | ||||
3 Design standard
Valves are designed as API600
Temperature-pressure rating as ASME B16.34
Flange ends as ASME B16.5 (≤24), ASME B16.34(NPS≥26)
Buttwelding ends as ASME B16.25
Test and check as API598
4 Structure
Flange globe valve structure:
