Howell-Bunger Discharge Valves were first developed and introduced for dam outlet works service in the early 1930’s by Mr. C. H. Howell and Mr. Howard P. Bunger, with the United States Bureau of Reclamation. VAG acquired the product line from Allis-Chalmers in 1990, has continued to develop the design for optimal performance and owns the trademark for Howell-Bunger Valves.
VAG KSSplus Howell-Bunger Discharge Valves provide controlled discharge of water while protecting the downstream environment. The valve breaks up the water into a large, hollow, expanding spray and can be used in most
situations, including submerged applications. An additional steel stationary hood concentrates the discharge spray
into a “jet” for a more controlled flow stream. They are ideally suited for low level outlet works for power projects,
turbine bypass, gate surge relief, flood control systems, irrigation facilities, and draining reservoirs or ponds.
Proven Performance
VAG KSSplus Howell-Bunger® Discharge Valves are proven performers with over 650 installations globally in the past 80 years.
Smooth, Vibration Free Operation
Cylindrical sleeve with adjustable sliding caps provide efficient, free-discharge operation for high and low heads, operating through the entire stroke range without vibration or cavitation.
Drip-Tight Sealing
Downstream primary metallic sealing, secondary flexible sealing, and upstream quad o-ring provide optimal sealing
performance and prevent twist, roll, and point loading.
Easy to Operate and Maintain
Long guides with adjustable sliding caps provide smooth, non-binding movement. Sealing can be replaced without
dismantling the valve from the line
Valve Operation
VAG KSSplus Howell-Bunger® Discharge Valves are typically operated by a manual, electric, or hydraulic actuator mounted above a double bevel gearbox. The gearbox transmits torque to the twin power screws (one on each side of valve) which in turn engage bronze thrust nuts to open (retract) or close (extend) the cylinder gate.
In open positions, flow is directed outward around the deflector cone at a 45° angle (approximate) in a wide spray pattern into the atmosphere, dissipating remaining hydraulic energy without erosion of the surrounding area. By using a stationary hood, the wide spray pattern is redirected inside the hood to create a jet-like stream. This is often helpful where the wide spray pattern of Howell-Bunger Valves is objectionable or subject to freezing or ice build-up. Depending on the application, a venting device may be required for cavitation-free operation.
Howell-Bunger Valves are manufactured from fabricated steel or if required completely in STAINLESS STEEL. Meanwhile VAG can proof couple of Stainless steel installations in the US.
Since 1935, over 650 VAG Howell-Bunger Discharge Valve have been installed in applications ranging from 8” valve with 1400’ of head, to a 112” valve with 209’ of head. In settings throughout the world, Howell-Bunger Valves have been the valve of choice wherever the control of water flow under free discharge is needed.