For protecting Positive Displacement pump from its dead heading, certain external over-pressure relief valves are often used. This relief valve has to be used so that if pump discharge pressure gets exceeded set cracking pressure then the valve will open for providing relief path.
Spring present in the valve actuators usually are adjustable, so users can set desired amount of relief cracking pressure at the valve simply by turning adjustment screw.
In these sanitary valves there will be “T” body valves having one manually adjusted spring. Its seat metals will have both Teflon and also metal seats, with ladder used at little higher pressure. You can find them with 50-pound, 100 pound and 300-pound springs.
Drawback to manual 60R valve will be the fine tuning which must occur for setting the relief valve. Its springs are not well calibrated, and hence for setting the relief pressure, you must tighten spring to its down and then in careful manner dial-in the cracking pressure just by adjusting the screw.
Positive Displacement Relief 1
This 60R is considered as “Can Do” kind of sanitary relief valve which has to be made pairing with another “can do” pump. This actuated sanitary valves of WR60 series which is of latest and also greatest among the sanitary relief valves.
All the features of WR60 valves are having an adjustable spring and maintenance-free actuator which are calibrated for making easy setting for any desired value of relief cracking pressure.
Also, they feature piston actuators which allow users to do bypassing of relief pressure setting by fully opening the valve meant for CIP cleaning activity, without any need of over pressurizing the valve.
Such multiple body styles can also provide minimal amount of dead-leg relief configuration. Similar to all seat valves, they also are available with solenoids, switch tops and proximity switches to get feedback and automation.
The WR60 series type of valves has one example of application is WR63 valve having CD body and also air-to-lower adjustable type spring actuator. This type of valve configuration, allows to get free draining and also minimal dead-leg relief piping.
Positive Displacement Relief 2
With the leverage of different configuration of valve body and also by taking benefits of well understood, quantified actuator sizing properly calculated, you can protect expensive type of process equipment and also can minimize all system dead legs to optimize cleaning.
You will need the help of a trained engineer, who can do all the selection and setting of the valves for your required process.