The needle valve is mainly designed for water flow rate and pressure regulation in a pipeline.
The regulation takes place thank the axial movement of the piston, operated by a rod and crank mechanism.
The piston is positioned in the center of the valve, in a chamber properly shaped in order to protect the piston from the water stream: this avoids noises and cavitation damages.
This characteristic allows also vibrations -free operation.
The water flow is guided in an annular chamber around the central body of the valve. The cross section of this chamber reduces continuously from the inlet up to the outlet. Because of this, the flow speed rises and the pressure falls.
The geometrically ideal design, allows to protect the pipe from the cavitation’s bubbles, which are directedtowards the center of the outlet mouth.
We suggest to operate our needle valves between 20 and 80% opening.
Due to the perfect balance between the upstream and downstream chambers, the needle valves need a low torque to be operated.
The operating mechanism consists in a glyph, a shaft, a connecting rod and two pins made of stainless steel. All the moving parts rotate on marine bronze bushings.
The seating ring is bolted onto the valve’s body and is made of stainless steel, it’s design ensures a perfect seal and an easy maintenance of the parts inside the valve.
The valve body is corrosion protected by a FBE (fusion bonded epoxy coating process) with a thickness of 250 μm, approved by the European laboratory for drinking water as Dvgw (Germany), WrC (U.K), DgS (France)
The valves are tested following the internationals rules UNI EN 1074-1 e ISO 5208-1982 (E).
Nero Needle Valves Specifications:
Maximum Temperature (C)
Minimum Temperature (C)
Pressure Nominal from (bar)
Pressure Nominal to (bar)
approved by the European laboratory
Ductile Iron GJS 400; or Ductile Iron GJS 500; or Cast Steel
Other parts' material
Piston: Stainless steel 14021; AISI 304 l Crank: Carbon steel, C40 l Fork: Carbon steel; C40