Sporlan solenoid valve Rapid Cycle Solenoid Valves
Sporlan Rapid Cycle Solenoid Valves are designed for appli-cations that require a solenoid valve to cycle frequently in a short period to maintain very close temperatures. An environ-mental test chamber using a mechanical refrigeration system is the most common application of rapid cycle solenoid valves. When rapid cycling a standard solenoid valve, typical failures are knocking out the enclosing tube top plug, cracking the enclosing tube, and mushrooming the plunger at the point of impact. Damage to the plunger is caused by the plunger strik-ing the bottom of the top plug with considerable force each time the valve is cycled. Developing a way to reduce the impact between the plunger and the top plug is an obvious design target. One way to accom-plish this is through the use of a low force coil. By applying a low force coil on a standard valve, the impact force is reduced since the low force coil has less pulling power. Sporlan developed the rapid cycle solenoid valve as a better means of reducing the impact between plunger and top plug and the associated premature failures. The rapid cycle series valves, can operate at a 250 psi maximum operating pressure differential (MOPD) on AC voltage and are suitable for either liquid or vapor refrigerant flow.
CONSTRUCTION
When comparing a rapid cycle valve with a standard valve, several design changes can be observed. The changes that increase the cycle life are as follows:
Enclosing Tube ° The enclosing tube is extended and the enclosing tube magnetic top plug is eliminated. This design changes the direction of magnetic pull on the plunger before it hits the top of the enclosing tube. Plunger ° A hammer blow plunger replaces the standard plunger and is used to assist in lifting the plunger stem off the pilot port. To further decrease the force of impact between the plunger and the enclosing tube, a synthetic bumper is added to the top of the plunger. Coil °An OMKC coil is used to allow the coil to °∞sit°± furth down on the enclosing tube. This slows the plunger once it accelerates across the coil center line. NOTE: Even though the rapid cycle valve uses an OMKC coil, they are normally closed valves.
