Nowadays in the manufacturing domain, there are many industries that work in the fluid control sector, producing and selling wide lines of check valves characterized by a very high quality. All this suppliers focus their attention on the selection of the best materials used to create these special and fundamental mechanical components. Some of these materials are the following ones:
- cast iron
- carbon steel
- stainless steel
- bronze
- marine bronze
Other very important steps in the production of these items are represented by the mechanical processes and by the treatment of surfaces. All the technological advanced modern engines can now be supported by the presence of very innovative check valves that have been developed to fully satisfy all the different needs of the most complex hydraulic systems that characterize many industrial machinery.
The main purpose of these valves is to maintain a set pressure in a given circuit, usually to counterbalance a weight or external force or counteract a weight keeping it from free-falling. The pressure setting is lightly higher than that needed to keep the load from free-falling. Specific counterbalance valves are commonly drained internally. When the cylinder extends, the valve open and its secondary port is linked to reservoir. When the cylinder retracts, the so-called hydraulic check valves bypasses the valve’s spool.
Overcenter valves and counterbalance valves have more or less the same function: as it has been already said, they aim at maintaining a set pressure opposite a load by keeping it from free-falling. Differing from counterbalance valves, the overcenter ones are characterized by a pilot signal that assists in opening the spool. This technical feature makes these particular valves much more functional and efficient by reducing the horsepower requirement and heat generation in the whole hydraulic system.
