Neddle Valves
What is a needle valve?
Needle valves, sometimes referred to as plunger valves, are regulating valves and enable engineers to finely control and regulate water flow and pressure. The precision is achieved through the fine movement of the shaft, which enables the gearbox to move the piston tube in sliding motion towards opening or closing position, depending on the requirements from the control system.
Needle valves can be used in many different applications with a need for flow or pressure regulation. In water treatment and distribution, dams, reservoirs, power plants and industry needle valves are e.g. used for:
- Flow control
- Pressure regulation
- Pump start
- Turbine by-pass
- Discharge
- Reservoir inlets
- Air regulation
Main features and benefits:
• One-piece body construction
• Stainless steel internal parts and fasteners for a long life of the valve
• All ductile iron parts coated with min.250 μm fusion bonded epoxy
• Shaft sealing with double O-rings
• Main seal in the no-flow zone at the valve outlet
• 4-6 guide rails ensure very low vibration
• Gaskets in thermoplastic PUR for high resistance to abrasion
• Pressure balance in chamber inside for low operating torque
• Symmetric flow path with annular flow cross section in any open position
• Internal body shape is optimised to give a low head loss coefficient in fully open position
Needle Valve Variants and Configuration
We offer a wide range of high quality needle valves in different configurations and with optional extras for actuation and cavitation prevention.
Dedicated software for precise size calculation Each valve is specified according to relevant selection criteria for its specific application. Upon order or request it is, therefore, mandatory to provide information about hydraulic data (flow rate and pressure), installation design and requested actuation. This ensures that the valve has an optimal performance for the given installation. By using our dedicated software for sizing calculations, we provide a fluid and cavitation report under the hydraulic conditions. The report will guarantee a cavitation free valve
Configurations
We offer a selection of optional extras for actuation and cavitation prevention. Each valve is fitted to the actual operating data and works
without cavitation even at major pressure differences.
Actuation
Upon request we can provide needle valve solutions with custom designed actuation
configurations:
• Worm gear box and handwheel
• Electric actuator
• Hydraulic
• Hydraulic brake and lift unit
• Double acting hydraulic piston
• Single acting hydraulic piston
• Double or single acting pneumatic actuator
Cavitation trim
Accessories are available for prevention of
cavitation:
• Intrusive
• Dissipating cylinder
• Non intrusive
• Dissipating plate
• Venting device
Intrusive
Dissipating cylinder
Non Intrusive
Dissipating plate
