311-312 Midi-Diaphragm Seals
The Ashcroft® 311 and 312 midi-diaphragm seals are fitted in confined areas to protect measuring instruments. Used to ensure process compatibility, they are also applied when process media exhibit pulsation. Ideal for limited space installations.
Key Features:
- Compact and lightweight design
- Choice of diaphragm and lower housing materials
- All-welded construction
- Volumetric displacement allows attachment to:
3 1/2″ gauges (Vac to 1,000 psi)
4 1/2″ gauges (30 to 1,000 psi)
Transducers and Switches - Rated up to 1,000 psi
Applications:
Process Market:
Oil and Gas
Refineries
Chemical and Petrochemical
Water and Wastewater
Process Applications:
Oil and Gas Fracking
NACE Compliant Processes (Sour Gas Separation)
Biogas and Biodiesel
Product Information
Specifications
- Process Connection Size
- 311: ¼ to 1 NPT Male or Female
- 312: ¼ or ½ NPT Female
- Instrument Connection
- ¼ or ½ NPT Female
- Pressure Rating
- 1,000 psi
- Added Tolerance
- ±0.5% typical
- Connection Style
- 311: All-Welded
- 312: All-Welded with flushing connection
Data Sheets:
Product/Technical Information:
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Resources & Tools
Min/Max Guide
IMPORTANT! When selecting a diaphragm seal or isolation ring, refer to the Min/Max Guide (PI page) for compatibility with this gauge.
Materials Selector
Use the selector to review compatible wetted materials and requirements of your application.
Unit Converter
Need to convert measurement units? Check out our quick and easy tool to convert pressure, temperature and flow units of measure.
Product Information
To learn more about the technical details for options available, review our product information (PI) pages.
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Configure Part Number
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