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Recent content by Prototyp

  1. Prototyp

    Water hammer & valve closing time

    Thank you for your help. Gerhard, it wouldn't be a problem if the actuation time is longer for example 60 seconds would be ok as well. I checked different suitable actuator/valve-combinations and the opening time varied between 10 and 30 seconds. Therefore I asked for pressure surges at 10...
  2. Prototyp

    Water hammer & valve closing time

    Usually many at the same time.
  3. Prototyp

    Water hammer & valve closing time

    Thank you LittleInch, I am not quite sure what you mean with pressure surge limit. The pressure rating of the piping is PN16. The headers size is DN150 and the braches with the actuated valves are DN50. The pumps are located aorund 20 m away from the first branch and 120 m away from the most...
  4. Prototyp

    Water hammer & valve closing time

    I am planning a water systems (flow velocity ~2.5 m/s, max. 8 bar) consisting of a header and several branches connected to the header by butterfly or ball valves. These valves are electrical actuated with an opening/closing time of approximately 10 seconds. I would like to check in advance if a...
  5. Prototyp

    Seal for sludge pump

    Which seal is best for sludge pumps considering: leakage maintenance price? Which seal is recommended?
  6. Prototyp

    butterfly lever uperated up to which size

    Thanks a lot for your help
  7. Prototyp

    butterfly lever uperated up to which size

    Up to which size can butterflys be actuated by lever? At which sizes is it receommended to use gear wheels instead of levers? What is approximately the price difference between a lever and a gear wheel?
  8. Prototyp

    Trapeze hangers and rods calculation

    For production hall piping we normally use trapeze hangers made out of sectional steel for multiple pipe runs and for single pipes mostly rods mounted to the roof. There is a lot of information available about pipe stress, thermal expansion, support width calculaton and so on but unfortunatly I...
  9. Prototyp

    How to read frequency from pump curve

    Why have 4 parallel pumps been condisered for this application. Wouldn't be one single VFD-pump sufficient?
  10. Prototyp

    Flow meter selection help

    Thanks for advice. Littleinch: yes, something like that Is there some rule of thumb how far the flow meter diameter can be reduced compeared to the pipe diameter? What is the limiting criteria, is it head loss? For example is reduction from ND150 to ND100 ok and how much head loss would result...
  11. Prototyp

    Flow meter selection help

    A flow meter should be placed in an grinding oil supply pipe. System data Fluid: grinding oil Supply pipe: ND150 (6 inch) Flow rate: 150 to 2300 l/min Flow pressure: 3.5 to 8 bar In this case I can only chosse between paddle wheel and vortex type, so other flow meter types don't need to be...
  12. Prototyp

    Where to place VFD's best

    We regulary install industrial fluid treatment systems with normally 3 VFD controlled pumps. Until now the VFD's have been placed in the PLC's electrical enclosure. Unfortunatly this often causes space problems inside the enclosure since the VFD's are really big serving pumps up to 90 kW. A...
  13. Prototyp

    combining ASME-laterals with EN pipes

    Thank you, I checked B31.3. The laterals I need can be butt-welded from the best available EN wall thickness pipes without needing reinforcement. Nevertheless it might be more cost-effective to buy ready-made laterals which stability is even higher because of the bigger wall thickness.
  14. Prototyp

    combining ASME-laterals with EN pipes

    MJCronin, when I am talking about ASME- or EN-based I mean the dimensions, inner diameter and wall thickness.

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