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Copyright © AVK Holding A/S, original version, rev. 1, 8-July-2021
4. Principle of operation
AVK diaphragm operated control valves can easily be altered to suit different functions with
additional option of replacing the control module, original main valve can be used.
The main control valve is pilot operated, capable of precise setting and easy adjustment of wanted
inlet pressure sustaining, back pressure or hydraulic un-loading applications.
Description
Condition
Upstream Pressure “
𝑃
1
” within area "A"
𝑃
1
× 𝐴
Valve outlet Pressure "
𝑃
2
" within area "B"
𝑃
2
× 𝐵
Control Chamber Pressure "
𝑃
3
" within area "C"
𝑃
3
× 𝐶
Spring Force of main valve
𝐹
spring
Opening Operation
(𝑃
1
× 𝐴) + (𝑃
2
× 𝐵) > (𝑃
3
× 𝐶) + 𝐹
spring
Closing Operation
(𝑃
1
× 𝐴) + (𝑃
2
× 𝐵) < (𝑃
3
× 𝐶) + 𝐹
spring
No Flow
𝑁𝑜 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒: 𝑃
1
= 𝑃
2
= 𝑃
3
