Hollow Jet Valve

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


Size (mm): 500-1800

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

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 manual and electrical. Both types come with a balancer chamber inside the valve (inside of the piston). Water goes into the chamber piston through the holes which are located on the face of the piston so it will reduce the hydrostatics pressure on the opposite surface of the 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 packings are absolutely sealed. The movement of the piston governs by means of a screw that is under control. The Hallow jet screw type will apply either a manual or electrical actuator which works via conic gears (bevel gear), stem, and stem nut.