MS4 / MSP4 Series - Aseptic Single Seat Valves

Product Type(s) : Single Seat Valves
Description :

The MS4 and MSP4 aseptic single seat valve series are designed for applications in the food, beverage, dairy, pharmaceutical and chemical industries.  These valves are available in shut-off, change over, and tank outlet configurations.




  • Innovative fan support mechanism extending the operating pressure range and the lifetime of the diaphragm
  • Flat easily cleanable single layer diaphragm design enabling immediate leakage detection
  • Suitable for process pressures of up to 145 psi (10 bar), depending on size
  • High temperature capability
  • A variety of valve body configurations enables efficient system designs
  • Easy and cost effective maintenance compared with bellows provides low cost of ownership
  • 3-A approved
  • MSP4 available with USP Class VI approved diaphragm and diaphragm shaft material
  • ATEX compliant models
Theory of Operation

How does an aseptic diaphragm valve work ?

The single layer diaphragm of the DELTA MS4 is made of TFM. The diaphragm, shaft and cone of the DELTA MSP4 is built from one TFM piece. The opening and closing of the valve is performed either by a pneumatic actuator or manually by means of a crank.

During opening and closing, the diaphragm is continuously supported by a unique fan support system, which relieves process pressure on the diaphragm, thus protecting it against overstress and/or pressure spikes. This system significantly increases diaphragm reliability and lifetime.


Fan Support System - Valve in Open and Closed Positions

  1. Yoke
  2. Reciprocating fan
  3. Valve housing
  4. Seat seal
  5. Valve shaft
  6. Diaphragm 50% supported
  1. Yoke
  2. Static fan
  3. Valve shaft
  4. Valve housing
  5. Seat seal
  6. Diaphragm 100% supported
Key Applications

Food & Beverage Processing

Dairy Processing

Pharmaceutical Processing

Chemical Processing


Sizes: 1" - 4" DN25 - DN100 Housing Configurations:

  • MS4: MS4: MS41 (L), MS42 (T), MSE41 (KLL), MSES45 (LLS), MST42 (T)
  • MSP4:  MSP4: MSP41 (L), MSP42 (T), MSPT42 (T)

Sterilization Temperature (approx. 20 min.): 

  • EPDM 302ºF (150ºC)
  • HNBR 284ºF (140ºC)

Control Air Pressure: Min. 87 psi (6 bar), max. 116 psi (8 bar) Product Wetted Parts: AISI 316 L (1.4404), AISI 304 (1.4304) Seal Material:

  • Seat seal: EPDM, HNBR, FPM
  • Diaphragm and Diaphragm shaft MSP: TFM


Valve configurations: Single seat valves:

  • DELTA MS4 
  • DELTA MSP4  (with diaphragm shaft made of PTFE)
  • DELTA MSR4 (with regulating cone)

Tank outlet valves:

  • DELTA MSTP4 (with diaphragm shaft made of PTFE)

Change over valves:



Pressure Ratings:

Operating Pressure:  Maximum line pressure: 145 psi (10 bar)

Temperature Ratings:

Operating temperature: Maximum  275ºF (135°C),  Short time 284ºF (140ºC) - no steam