Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by checman

  1. checman

    API vs. ANSI pumps

    I have worked with many fuel terminals in the past. Most all not attached to a refinery have used ANSI pumps. One that did use API pumps that comes to mind was built when a company was flush with cash but they could not afford to overhaul the pumps 15 years later. Even a stainless steel pump...
  2. checman

    LPG PUMP CAVITATION PROBLEM

    I meant the NPSHR of the butane pump may be more
  3. checman

    LPG PUMP CAVITATION PROBLEM

    Are the flow rates the exactly the same? The NPSHA maybe very close to each other but the NPSHR maybe greater for the propane service depending on where or how fast you are discharging it. Cavitation sounds may get worse in the winter because the delta T may be greater if so then the energy...
  4. checman

    Piping Forces on Centrifugal Pump Connections

    You are right I normally count on the piping designer and stress engineer to get the piping close. I also fix ANSI pump problems created when engineers and owners try to save some money. There is no good reason to plan on loading an ANSI pump flange. I should have said that I redesigned piping...
  5. checman

    Piping Forces on Centrifugal Pump Connections

    JohnSr When I suggested an expansion joint may take up the load I was not suggesting you go to expansion joints are us to get one or order one from fly by night industries. Go to a company like Hyspan, they will ask for all the pertinent information and may even do the calculations for you if...
  6. checman

    Piping Forces on Centrifugal Pump Connections

    John Goulds does have that information available. You need to contact the Goulds rep in your area or ask Goulds online. A good expansion joint with limiting rods may take up the load and keep the pump components in line and running smooth.
  7. checman

    Acceleration head

    Alanator; The pressure drop you might see would depend on how flat of a curve the centrifugal pump and the capacity of both pumps. If the feed pump curve is flat and the capacity of the feed pump exceeds the reciprocating pumps capacity the pressure may not fluctuate much. The glycerin filled...
  8. checman

    pump discharges at various elevations

    burkATO Put a gauge at the pump suction and discharge correct for specific gravity then plot the differential head on the pump curve.
  9. checman

    VFD and Minimum Flow Valve

    A VFD on a centrifugal pump for boiler feed water may not be a good investment unless the boiler is sometimes operated at a lower pressure. Some systems run at high pressure in the winter and low pressure in the summer on these systems a VFD can pay for itself. With most boiler feed systems the...
  10. checman

    Eccentric reducer at pump suction

    Using eccentric reducers on the horizontal run of suction piping is technical and very important in most all pump installations. How can you calculate line loses in the suction pipe if the liquid is forced through only part of the pipe because the rest of the pipe is occupied by a large air...
  11. checman

    Holding suction after pump shuts down

    mrelet You may have the siphon effect working against you. If you notice that the pad is released after the discharge line drains it may be the problem.
  12. checman

    Pump Cavitation

    I would agree with Zapster. But many things would influence the outcome. Suction pressure, the fluids specific heat and other characteristics, the pumps efficiency, the pumps clearances and so on. If the pump has a high specific suction speed you would most likely develop incipient clouds of...
  13. checman

    Backpressure Valve Placement

    RJB32482 The back pressure valve on this type of pump is normally to help the checks make a positive seat in viscous liquids. It will most likely work wherever you put it in the line. I like to put the back pressure valve right after the surge suppressor and I like the surge suppressor right...
  14. checman

    startup of a rotary pump

    IR56 This site has some good general information on pd pumps. Regards checman http://www.vikingpump.com/engineering_data/engineering.htm
  15. checman

    Double Volute vs Single Volute

    I would agree with Artisi especially on the efficiency. A small change in efficiency can add up to big dollars on large pumps that run often. I would also like to add that it could lower the cost for the supplier to manufacture the pumps substantially. With the double volute you have lower shaft...
See more

Part and Inventory Search

Back
Top