The comprehensive line of Ashcroft® diaphragm seals will meet a wide variety of application or installation requirements. Over 30,000 variations are possible with the types, connections and materials available.
The top housing and diaphragm capsule are interchangeable with all Ashcroft bottom housings.
A fill/bleed connection is standard, which permits filling the seal and instrument simultaneously after evacuation and allows the fill to flow into the completed unit.

A Viton® O-ring, compatible with all standard fill fluids, and a Teflon® back-up ring provide a seal between the diaphragm capsule and the top housing.
The diaphragm is Teflon® coated to provide an integral gasket, thus assuring a leak-tight connection between the diaphragm and the bottom housing.
Top housing and pressure instrument are removable.
Continuous-duty design will prevent loss of process fluid if pressure instrument is removed or fails.

Teflon® coated, continuous-duty diaphragm capsule is welded to the top housing, which is then clamped to a bottom housing. Fill/bleed connection is standard. Top housing and pressure instrument are removable. Available in same process connections, materials, types and sizes as the Type 100 capsule design. Top housing is interchangeable with all standard Ashcroft bottom housings.

Type 200 Bonded Viton® Similar in construction, materials, and product features to the Type 300 clamped Viton® diaphragm seal, the Viton® diaphragm in the Type 200 seal is bonded permanently to the top housing, and is the removable type.

Lowest cost metal diaphragm seal in the Ashcroft line. Broad selection of materials... for meeting various service applications, including Teflon®, Viton® and Kalrez® diaphragms. Teflon®-coated metal or elastomeric diaphragm is clamped securely between the top and bottom housings by clamp rings, assuring positive seal. Top housing is contoured to match diaphragm, minimizing distortion of the diaphragm (all except

Viton® and Kalrez®) should the pressure instrument be removed. Continuous duty. Fill/bleed connection is standard. Top housing and diaphragm are nonremovable. Metal diaphragm only available in 0.25" to 1" threaded inlet sizes. Teflon®, Viton® and Kalrez® diaphragms available in threaded and flanged inlet connections.

Compact size to fit space-restricted areas. Designed to protect transducers, miniswitches and 3.5" or smaller pressure gauges from corrosion, plugging or freeze-up All-welded metal construction prevents leakage of process media Rated for 2500 psi at 100°F Fill/bleed connection is standard

• All-welded metal construction, prevents leakage of process media
• No gaskets or bolts
• Top housing material 316L stainless steel standard
• Diaphragm materials in 316L stainless steel, Hastelloy C and Tantalum
• Bottom materials in 316L stainless steel and Hastelloy C
• ¼NPT or ½NPT instrument connections
• Type 312 furnished with ¹/₈ flushing connection
• Compact design

• For use on Bourdon tube gauges up to 3½" from vacuum to 1000 psi and 4½" pressure gauges 100 to 1000 psi
• Also for use on direct drive gauges to 4½"
• Adds anadditional 1% tolerance to instrument

The Ashcroft® Type 320 quick-connect diaphragm seal is designed especially for those applications that require ease of dismantling and re-assembly and do not require a 3A standard rating in accordance with sanitary standard 37-01. Typical applications include the pharmaceutical, dairy, food processing, biotechnology, and filtration markets. Also included are breweries, distilleries, wineries and citrus juice production plants.

Standard features include:

• 316L stainless steel diaphragm welded to a 316L stainless steel top housing.
• Fill/Bleed connection
• Top housing and pressure instrument removable from process.
• Compatible with Tri-Clover and Cherry Burrell S line connections.

• All-welded metal construction, prevents leakage of process media
• Flush design eliminates clogging or media build-up
• Easy to clean up
• 1"MNPT process connection
• Compact size
• No gaskets or bolts
• Top housing, diaphragm material 316L stainless steel

• For use on pressure gauges up to 3½" from vacuum to 1000 psi
• Also for use on direct drive gauges to 4½"
• Adds an additional 1% tolerance to instrument

Recommended for use where clamped joints are not acceptable

Assists in controlling plant emissions by helping prevent potential leakage of hazardous chemicals

Prevents inadvertent disassembly

All-stainless steel construction is standard. Other materials available

With the Ashcroft® Isolation Ring, the instrument is in contact with the fill fluid, not directly with the process flow. Clogging or fouling is never a problem. The Iso-Ring has a flexible inner cylinder, behind which is the fill fluid. As process liquid flows through the pip, it exerts pressure. The pressure exerted by the fill fluid is then monitored by the instrument-sensing element. A 360-degree flexible cylinder means no plugging, assuring reliable and accurate pressure readings. A built-in threaded needle valve is provided as standard. This permits the removal of a pressure instrument for calibration repair, or replacement without shutting down the process flow.

Adaptable to a variety of process conditions and applications, the Ashcroft Iso-Ring can be used for protection of instrumentation such as pressure gauges, switches, transmitters, recorders and transducers. The Iso-Ring fits between customer-supplied piping flanges like many butterfly valves, and is available for piping diameters from 2" to 20". It can be used at any pressure within the limitations of ASME classes 150 and 300, and even in most vacuum applications.

Ashcroft® Type 85 and 86 Iso-Spools are used for small-diameter piping. Designed to provide a large sensing area in the smaller pipe diameters from 1" to 2", the patented Iso-Spool is offered in either NPT threaded or flanged models. Type 86 is available with flat or raised-face flanges.

• For low pressure instruments 10"H₂O to 200 psi
• Used in instruments with large displacement actuators
• For applications requiring an impermeable metallic diaphragm
• Available in many material combinations

• Diaphragm electron beam welded to isolator body
• ¼ or ½ NPT process connection; other sized on application
• ¼ or ½ NPT instrument connection
• Furnished with fill/bleed connection