When our customers came to us with the need for a valve that could withstand the rigors of daily handling and operation on the foam machine platform and consistently prevent metering pump “dead-head,” we came up with this design.
Our goal: supply a high performance ball valve coupled to a limit switch that would ignore rugged use including the splash of chemicals which are commonly found on a polyurethane foam pourline.
Now the Cushman Engineering, Inc. Safety Cutoff Valve has two SPDT switches
The result is our new Safety Cutoff Valve (SCV5)
• Based on a Swagelok three-piece 60 series ball valve with our custom designed armored limit switch.
• Working pressure is 2,200 psi. Full port design.
• The limit switch housing is machined from billet 6061 aluminum.
• The cam shaft connecting the handle to the valve is 4140 steel.
• The shaft and housing form a sealed mechanism around the switch and cam. The shaft is sealed with EPDM O-rings and the two halves of the housing are sealed with RTV Silicone.
• Supplied with 5 feet 20/7 AWG, .32" OD, 600 VAC cable which can be connected to the customer’s control system.
• The limit switch box is equipped with 2 SPDT mini switches. One SPDT switch is actuated when the valve is fully open, the other SPDT switch is actuated when the valve is fully shut.
© Tom Cushman 2017