Also known as balanced valves or plunger valves, Flowrates annular valves are engineered for high-precision flow regulation in high-pressure, large-scale water networks.
Thanks to their precise linear mechanism, the piston ensures reliable and progressive control between open and closed positions — even under the most demanding hydraulic conditions.
Where are Needle valves Installed ?
Our valves are perfectly suited for installations requiring accurate flow or pressure regulation, such as:
Water treatment and distribution systems
Hydropower plants and dams
Large storage reservoirs
Industrial and nuclear facilities
Their main functions include:
✔ Flow and pressure regulation
✔ Pump priming
✔ Turbine by-pass
✔ Discharge and reservoir inlet
✔ Air regulation
When to choose an annular valve?
Unlike standard control valves, annular valves can operate under very high differential pressures without performance loss.
Our range covers:
Standard pressures up to PN40 (and up to PN100 on request)
Diameters from DN80 to DN2500
Operation modes: manual, electric, hydraulic, or pneumatic
Flowrates Technology
Each annular valve is designed with a monobloc body optimized for flow, reducing head losses when fully open.
This architecture ensures:
Very low operating torque, thanks to full hydraulic balance of the piston (equal forces on both sides at any position).
Reduced actuator and gearbox costs (smaller sizing, lower power and energy consumption).
Stable performance even under high differential pressure conditions.
Quality and durability
Our valves are built to last:
Moving parts made of Stainless Steel
Body fully protected with a fusion-bonded epoxy coating
Long-life seals, with the main seal located outside the fluid and easily replaceable without dismantling the valve
Compact piston, ensuring very low vibration levels
Every Needle valve provided by Flowrates undergoes strict quality testing on both static and dynamic test benches, monitored by experienced technicians.
Tailor made solution
At Flowrates, every valve is designed to match your project:
Analysis of hydraulic data (flow, pressure)
Review of installation design
Selection of the most suitable actuation method (manual, electric, hydraulic, pneumatic)
👉 Using our sizing tool, we provide a detailed performance report including flow characteristics, head loss, and cavitation risk. This ensures a cavitation-free valve, perfectly adapted to your installation.
Available configurations
Our annular valves can be equipped with a wide range of options:
Handwheel or electric actuation (on/off or modulating control)
Pneumatic or hydraulic actuator (single or double acting)
Hydraulic damper with counterweight
Anti-cavitation devices (slotted cylinder, perforated design, or V-Port Crown)
- Air Inlet Device
