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Development of one-piece needle valves

Ort: MidEast

The way to the one-piece housing:

The path to the one-piece needle valve was subject to some technical challenges that the ERHARD engineering team mastered excellently. Among other things, the redesign of the individual components had to ensure that the whole nominal diameter range of the needle valves with one-piece body, remain easy to install. The conversion to a one-piece body construction also contributes to the optimization of some other functions:

  • Range enlargement provides better controllability and flexibility in use
  • Reduction of torque
  • Increase the flow rate
  • Reduction of production lead times

Due to the mentioned advantages of one-piece body, this design will be now extended to the other nominal diameter range of the needle valves.

Project details:

One of the first projects that utilized the new design involved transmitting desalinated water from sea level to a height of 1800 meters. The 300 kilometer transmission line carried 4.4m3/sec  water through series of seven pump stations that consumed a total of about 145 MW. The ERHARD needle valves are installed at critical points in the transport and control system, and play an essential role in overall stability, reliability and functionality, and thus for the successful operation of the total system.

Technical Details:

  • Nominal diameter: DN 600 - 1200
  • Nominal pressure: PN63 / PN40 / PN25
  • Material body: N-GJS-400-18-LT / ductile cast iron
  • Coating: Epoxy
  • Actuator: Electric actuator


  • ERHARD GmbH & Co. KG
  • Meeboldstra├če 22
  • 89522 Heidenheim, Germany