Valves grant stop in position of a load, they are mounted on single acting cylinders, they need a pilot pressure to release the load.
The external body is made of high resistance steel and externally protected from oxidations by zinc treatment. On request we can supply a zinc/nickel treatment to increase the corrosion resistance when the valve has poor protection and it is located in external environments.
The sealing is granted by a tapered poppet hardened and grinded.