Diaphragm valve DIASTAR Ten ABS FO PN10 solvent cement d20-d63

  Datasheet (PDF)

The Georg Fischer DIASTAR Ten ABS FO is a pneumatically actuated diaphragm valve engineered for industrial process automation, chilled water loops, and water treatment systems. Available across metric diameters d20 to d63 with PN10 nominal pressure at 20 degrees, this valve features a fail-safe to open configuration, an ABS body, a PTFE seat, and an EPDM seal, supplied across Europe by BigWeld as an authorised Georg Fischer distributor.

Technical specifications

The DIASTAR Ten pneumatic actuator provides reliable linear stroke operation with a fail-safe to open spring mechanism that returns the valve to the open state during control air interruptions. This ensures process continuity and prevents fluid deadheading in critical circuits.

Engineered with a streamlined internal flow contour, the valve delivers double the flow capacity within an optimised, compact envelope. Key technical parameters include:

• Operation mode: Pneumatic fail-safe to open (FO) with internal return spring
• Nominal pressure: PN10 at a reference temperature of 20 degrees
• Size range: Metric diameters d20, d25, d32, d40, d50, and d63 mm
• Sealing materials: High-performance PTFE seat paired with an EPDM seal
• Body material: Acrylonitrile butadiene styrene (ABS) in RAL 7001 gravel grey
• Actuator construction: Glass-fibre reinforced polypropylene housing with a single union nut

Applications

The fail-safe to open characteristic makes this diaphragm valve the preferred solution for cooling distribution networks, chiller bypasses, and secondary refrigeration loops. In these duties, maintaining open flow upon power or instrument air loss prevents pump cavitation and thermal escalation.

The valve is equally suited for demineralised water systems, industrial water treatment plants, marine process piping, and drinking water utilities. Because the ABS body and diaphragm configuration keep mechanical components isolated from the conveyed fluid, the valve maintains continuous resistance to abrasion, scaling, and chemical degradation across varied utility environments.

Installation and jointing

Jointing is carried out via metric solvent cement sockets designed for homogeneous solvent cementing to metric ABS pipes and fittings. Connections require Tangit ABS solvent cement and matching cleaner to guarantee full mechanical and hydrostatic pressure integrity.

The pneumatic actuator features control air connections that rotate 90 degrees, allowing instrument tubing to be routed cleanly in tight skids or congested pipe racks. Mechanical servicing is simplified by a central housing nut, allowing rapid diaphragm inspection and replacement without dismounting the entire valve body from the pipeline.