The Oleoweb valves of the VBZD series are double overcenter valves, suitable for managing and controlling the movement of bidirectional loads. They are valves for installation in line with GAS threaded ports in sizes from BSPP ¼ to BSPP ½ "for recommended working flows up to 60 lpm (15,9 gpm). The fixed setting allows to optimize the installation times and avoid possible tampering with the valve setting. Load management takes place on the return lines from the cylinder, while supply supply is possible through a one-way valve. Thanks to the pilot line with the relative reduction ratio it is possible to manage the gradual opening of the valve to control the descent of the actuator even in the presence of gravitational loads that do not generate pressure. The VBZD valve can also work as an anti-shock valve protecting the system and the structure connected to it from damage caused by pressure peaks. This is possible only if the system distributor has the spool with open center in neutral position. Oleoweb pays particular attention to the realization of the components that realize the hydraulic seal of the counterbalance valves, carefully verifying geometrical dimensions and tolerances, as well as testing the sealing of the assembled valve. The VBZD counterbalance valves are parts in body valves: all the components are housed inside a hydraulic manifold. This solution allows you to manage high flow rates while keeping down the overall dimensions. Body and external components are made of zinc-plated steel. The zinc-nickel treatment is available on request to improve corrosion resistance. Thanks to the steel body it is possible to work with operating pressures up to 350 bar (5075 PSI).