Diaphragm Valve
A diaphragm valve throttles or isolates flow with a flexible diaphragm that presses against a weir. It has no dead leg and drains fully, which is why it is preferred for aseptic pharmaceutical and biotech service.
What is a Diaphragm Valve
The diaphragm separates the fluid from the actuator, so only the diaphragm and body weir contact the process. An electropolished 316L bore and crevice-free geometry support validated CIP/SIP loops.
Materials & standards
- Electropolished 316L stainless body and weir
- PTFE or EPDM diaphragm by fluid
- Tri-clamp (3A) hygienic ends
- Manual, pneumatic or actuator options
- Crevice-free, full-drain geometry
Typical applications
- Aseptic pharmaceutical and biotech loops
- Sterile filtration and WFI skids
- Food, dairy and beverage CIP/SIP
- Sampling and drain valves
- Aggressive CIP chemicals
Diaphragm Valve at a glance
| Sealing | Tight, weir-seated |
|---|---|
| Cleanability | Best — no dead leg, full drain |
| Relative cost | Higher than ball/butterfly |
| Best use | Aseptic, validated, drainable service |
Frequently asked questions
Which sanitary valve is best for aseptic pharma lines?
Diaphragm valves: no dead legs, full drainability and tolerance of aggressive CIP/SIP, usually with an electropolished 316L bore.
What diaphragm material should I choose?
PTFE for chemical resistance and steam; EPDM for general food/dairy duty. Match to the fluid and SIP temperature.
Can a diaphragm valve modulate?
Yes, with a positioned actuator, though it is primarily an on/off and throttling valve for hygienic duty.
Last updated: 2026-10-08
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