Schubert & Salzer Control Systems introduces the 7078 pinch valves and 7079 pinch control valves. The key improvements include compact construction with rotating piston actuator, all-wetted metal parts made from 1.4435 1.4408 stainless steel body, FDA-compliant seal for hygienic applications, working pressures up to 6 bar, FDA-compliant sleeve materials made from NBR or EPDM and sleeves with reinforced woven fabric to increase service life.
Together with a collet and union nut, a new type of fastener (fitting) provides a permanently drop-tight connection between the pinch valve and optional connections with a female thread, welding ends, tri-clamp or even adhesive sockets.
In these pinch valves, the reduction in cross section is brought about by a plunger acting on one side only. Previously, a sleeve section made specially to fit into the cross section had to be used for this. Now, this change in cross section is achieved by a new body design rather than requiring a specially molded sleeve.
This has helped improve flow coefficients. In the new series, depending on the size, these can be up to 50 percent above the Kvs coefficients of the previous series. Another result of this design optimization shows up in an extension to the service life of the sleeves. The previously achievable cycles of several 100,000 can now be doubled on the average – depending on the sleeve material and its diameter.