Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  1. raronen

    Increase pump efficiency by reducing running clearances

    Artisi, The modifications you note are all additional methods of improving efficiency. A user looking to maximize efficiency would do everything you note AND reduce the wear ring clearance. They are mutually exclusive improvements. Reducing wear ring clearance also provides benefits beyond any...
  2. raronen

    Increase pump efficiency by reducing running clearances

    I apologize for being a bit late to the thread, so I hope FFV5 will get this answer. Reducing wear ring clearance has several positive impacts on pump performance. True, the head curve increases; however, the efficiency increases by a greater amount. If we look at the pump horsepower...
  3. raronen

    misunderstanding in plan 52 + 53 + tandem seal !!

    In many situations, either Plan 52 or 53 will work. In the refining and chemical industries, the choice is based on the following criteria: If absolutely zero leakage is required, a pressurized plan 53 is required. The challenges with a Plan 53 are: - Requirement for a dual-balanced seal...
  4. raronen

    Pump Recirculation - Your Opinion

    Ditto the other comments--plot the point on the curve. Also, calculate the suction specific speed of the pump and follow typical guidelines for minimum flow as % of BEP based on the suction specific speed. Basically, the higher the suction specific speed, the closer your pump needs to run to...
  5. raronen

    Vertical Turbine Pump: Balancing correction vs Components wear out

    Tough question (not even BigInch took a crack at it). It sounds like you (like almost everyone else) are monitoring the vibration of the pump from the readings above ground. Of course, as your OP mentions, the source of vibration is below ground and the readings above ground therefore have some...
  6. raronen

    Suitable seal flush plan for Vertical In-line Pumps

    bk19702 is correct. An API Plan 14 is likely what you want. However, I am making some assumptions in this conclusion. First, because you are using a single seal, I assume your process fluid is not hazardous. Second, because you do not mention cooling, I assume the process fluid is not at an...
  7. raronen

    Small pump for liquid pentane

    In addition to Sundyne, you might also want to check out Roth pumps.
  8. raronen

    Minimum flow issue

    raronen I'm not completely sure if I can apply your formula, it could serve as a reference, but like bigInch says, it depends of the robustness of the pump. Suction specific speed is only a reference, however, it is extremely relevant to the pump selection you are facing. Hydraulically, the...
  9. raronen

    Minimum flow issue

    Before making a selection, I would recommend calculating the suction specific speed of the pump in question. S = (N*(GPM^0.5))/(NPSHR^0.75) *(N speed in RPM) *(GPM at BEP, for double suction impeller divide total flow by 2) *(NPSHR in feet) Studies have shown that pumps with higher suction...
  10. raronen

    PUMP HORSE POWER QUESTION

    dkm0038, (hydrualic horsepower) = (total head)x(flow rate)/(constant) does the above equation mean that if I have a certain hp pump then the flow rate will vary with the total head, or does it mean that I will have a certain flow rate and the horse power being drawn from the pump will vary...
  11. raronen

    Large Pump Mnufacturer

    As others have noted, Sulzer, Flowserve, KSB, Goulds should be considered. I'd also add ClydeUnion (Union and Weir pump product lines) and Ruhrpumpen to my list in order to explore all options.
  12. raronen

    pump configurations for variable flow system

    "The pumping requirement is to keep a constant pressure in the pipe." To follow up on what BigInch wrote, I think this pretty might answer the question. If it is a water system for a building, then the pumping system needs to be capable of overcoming the static head, which I assume is the...
  13. raronen

    Pure oil Mist lubrication

    I agree with JJPellin. I have worked in several oil refineries and all of them were using pure oil mist lubrication on hundreds of pumps. The reliability benefits from this technology far outweigh any safety issues. Just to back up the safety of a well-engineered system. A large percentage (I...
  14. raronen

    Newbie with a big problem

    I would develop an approximate "system curve" for all that piping. A system curve will have the equation y = mx^2 + b, where: y is the head required x is the flow rate m is the friction loss factor in the sytem b is the static head So, you need to solve for m and b to know the curve. "b" is...
  15. raronen

    CAVITATION

    Cavitation is a complicated issue, and you should be very careful about identifying the root cause before spending big money on new pumps. There are 4 common suction problems which can lead to cavitation-like symptoms: inadequate NPSHA, air entrainment, vortexing, and turbulence. It sounds like...
Back
Top