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  • Mirab Co.

Hollow Jet Valve

Size (mm) : 500-1800
Pressure rating : 6-25 (bar)
Body Material: All Types of Ductile Cast Iron, Carbon Steel
Sealing Cylinder Material: Stainless Steel

In dam application, control valves such as Hollow jet valves are installed after the butterfly valves on the outlet side. These valves always work as flow regulating or control valves. Hallow jet valves designed to perform regulating or control function in water supply system without any vibration as much as valve opening.
The Hollow jet valves are often used for the discharge into free atmosphere. However in some cases the valves can be used in a submerged condition where the downstream level is above the altitude of the installation. In such cases in order to in ensure proper energy dissipation, a dissipation chamber with a specific hydraulic profile is required so as to properly aerate the flow, avoiding hydraulic instability phenomenon. Reliable and adjustable discharge of large water flows having low or high pressure requires large energy dissipation with causing cavitation or excessive vibrations. The Hollow jet valve or fixed cone valve ensures very efficient control and closure and provide on economic solution for dam bottom discharge or other energy dissipating system. The design of Hollow jet valve, ensures excellent hydraulic performances, which can be highlighted by a stable discharge. The energy dissipation is achieved with excellent conditions and ensures a symmetrical flow.

Paint Coating :
Electrostatic epoxy powder (RAL 5005 or 5015) with min. thickness 250 micron.

Hallow screw type :

These valves are divided into two main groups of manual and electrical. Both types come with a balancer chamber inside of the valve (inside of piston). Water goes in the chamber piston through the holes which are located on the face of piston so it will reduce the hydrostatics pressure in opposite surface of piston, this means that pressure adjusting needs less force to obtain the minimum adjustment. Comparing Hallow jet valves with other valves, the adjustment force in Hallow jet valves is much less than others when the piston is thoroughly closed, all the packing’s are absolute sealed. The movement of piston governs by means of a screw which is under control. The Hallow jet screw type will apply either manual or electrical actuator which works via conic gears (bevel gear), stem and stem nut.