Fixed Cone Free Discharge Valves
Engineered for precise flow regulation while ensuring safe and efficient water discharge
Fixed Cone Free Discharge Valves (also known as Hollow Jet Valves) are engineered for precise flow regulation while ensuring safe and efficient water discharge. These valves are ideal for applications where high-energy water release needs to be managed without causing damage to downstream structures. Their unique design dissipates energy through atmospheric dispersion, making them the preferred solution for dam outlets, reservoir drawdowns, and flood control applications.
Glenfield Invicta has been designing and supplying Fixed Cone Valves since the 1950s. Our extensive field experience, combined with advanced modelling expertise (Finite Element Analysis (FEA) and computational fluid dynamics (CFD) and hydraulic testing, ensures that our valves meet the highest performance and durability standards.
How It Works
Fixed Cone Free Discharge Valves operate by releasing water in a controlled, expanding hollow jet. This jet interacts with the atmosphere, breaking up the flow and dissipating energy before the water reaches the downstream environment. Unlike traditional discharge valves, this design prevents cavitation and minimises vibration, ensuring smooth and controlled water flow.
Key Design Elements
- Cylindrical Valve Body – A robust ductile iron or fabricated stainless-steel structure designed to withstand high hydraulic loads and provide long service life. Symmetrical flow discharge characteristics, ensuing operating effort and vibration is minimised.
- Fixed Cone Outlet – Forms a controlled, expanding jet for effective energy dissipation. High discharge coefficient characteristics and valves can operate effectively when subjected to considerable flow velocities.
- Internal Sleeve – A stainless steel sliding sleeve with upstream and downstream seals, ensuring drop-tight shutoff.
Aerodynamically Shaped Ribs – Provide structural support while minimising turbulence and maintaining a stable flow pattern. - External Operating Mechanism – Ensures easy access for maintenance, reducing operational downtime.
- Actuation – valves can be operated manually, electrically or hydraulically
- Optional Hood – hood can be supplied to maintain the exiting discharge jet within a specific space envelope.
Applications
- Dams & Reservoirs – Safe and controlled water release for ecological flow compensation, emergency drawdowns, and flood management.
- Hydropower – Reliable turbine bypass operation for water flow regulation.
- Flood Control – Protection against high-energy discharges to prevent downstream erosion and structural damage.
- Municipal & Industrial Water Systems – Used for pressure relief and excess water discharge in large-scale infrastructure.
Engineering Support & Site Services
At Glenfield Invicta, we provide full technical support to ensure the successful sizing, specification, installation, commissioning and operation of our Fixed Cone Free Discharge Valves. Our engineering team offers site surveys, hydraulic modelling, and custom valve design to meet site-specific requirements.
We also provide installation supervision, commissioning, and maintenance services to maximise valve performance and longevity. Whether you require a new installation, refurbishment, or servicing, our experts are available to assist at every stage of the project, ensuring reliable and efficient operation for years to come.
For expert guidance on Free Discharge Valves, speak with our dedicated Dams and Reservoirs expert Greg Morris today:
greg.morris@glenfieldinvicta.co.uk
