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 cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. Snickster

    Connection Between Tanks

    I guess if you want to equalize water levels in the two tanks you just open the valve in the connecting pipe. Also if you want to fill at a rate higher than the vents of one tank is designed for you could fill both tanks at same time with 1/2 water level rise per unit time and vent rate shared...
  2. Snickster

    Process Chill Water Loop for Multiple Machines with varying requirement.

    I am not an expert on hydronic systems but it looks like you have it piped up wrong. You cannot take off of a single supply/return line and dump back into it unless you have individual pump units at each machine take off to force the flow through each machine. Without a pump at each machine...
  3. Snickster

    Pump modifications

    So you are relocating the pump to reduce pressure losses in system. Why would this require changing the impeller? Regardless changing of the impeller should be done with assistance of the equipment manufacturer.
  4. Snickster

    Two Pumps of Different Product and Ratings Pumping into a Common Header

    If I were you I would start from scratch and do my own detailed hydraulic calculations. You are trying to design based on information you are getting in piecemeal. I would get the process engineers to give you a complete process flow diagram with system flowrate, process pressures...
  5. Snickster

    Flow inconsistence

    First figure out what flow you really want/need. What flow is required by your process? How much flow are you trying to deaerate in your system? 1,8 m3/hr? 4 m3/hr? Once you determine the required flowrate of your system, check the required head output of each pump in meters at that flow. For...
  6. Snickster

    Flow inconsistence

    My understanding from your numerous previous posts that you are taking existing pumps from somewhere and placing them in systems they were not originally designed for. I think that is why there is such a mis-match in stated design flow rates of the two pumps. Correct? These are some of these...
  7. Snickster

    PSV sizing acc. to IGC

    The attached Appendix 3 provides a derivation of the conversion of relief flow to standard cubic feet of air.
  8. Snickster

    PSV sizing acc. to IGC

    Also see the attached.
  9. Snickster

    PSV sizing acc. to IGC

    See attached API 2000 Appendix D and in particular D-9.
  10. Snickster

    PSV Inlet and Outlet Pressure Drop Calculation Question

    Now I want to calculate the Reaction Force at the PSV outlet flange. The momentum force is same at the PSV Exit flange. For the Pressure force I think I should use the Back pressure acting at the PSV as the value for P in the formula Pressure Force =A*P, and the Area A would be PSV outlet flange...
  11. Snickster

    pumps

    It could be that your downstream pump system is ok and does not have very high friction losses and it is just that your upstream pump flowrate is restricted due to the high pressure drop across the nozzles to get the spray. The downstream pump even if ok can only pump what flow it is supplied...
  12. Snickster

    pumps

    If you are measuring 1.8 m3/hr on the second pump then that is what the flow really is. Your pumps may be rated for 4 and 9 m3/hr but how much they really pump has to do with the pressure loss at a given flow in your system. This is where the system curve intersects the pumps curve. For the...
  13. Snickster

    Relieving temperature PSV

    Oh you mean the temperature of the discharge considering a constant enthalpy expansion across the relief valve? Ideally the temperature upstream of the relief valve equals the temperature downstream of the relief valve adjusted for the Joule Tompson Effect cooling, and for increase in velocity...
  14. Snickster

    PSV Inlet and Outlet Pressure Drop Calculation Question

    Pavan I will get back with you on your latest posts,
  15. Snickster

    PSV Inlet and Outlet Pressure Drop Calculation Question

    These are just basic compressible gas flow equations for solving pressure drop in relief systems, sizing relief valves, and determining reaction forces due to relief valve discharge. If you don't understand them you should not be designing compressible flow relief system even if you have...
  16. Snickster

    Relieving temperature PSV

    1. I agree with goutam. It has been a while since I did a fire calculation but I believe the worse case for relieving requirements is if the vessel was partially filled with liquid as this configuration absorbs the most heat per API 521. Per API 521 a vessel with all gas absorbs relatively...
  17. Snickster

    Compensating pressure in Cryogenic Storage Tank

    I cannot comment on your calculation for pressure drop in tank during unloading without more details like volume of tank and initial vapor space, etc. as others have indicated. However I did a calculation to determine the required flowrate of liquid CO2 to a vaporizer/heater for vaporizing into...
  18. Snickster

    PSV Inlet and Outlet Pressure Drop Calculation Question

    Further to the above explanation: Without calculating the actual mach no, and stagnation temperature To at your upstream conditions P1, V1, T1, I just assumed that T1 of 92 F was approximately To stagnation temperature. That is why I stated in my previous comments that I was assuming low...
  19. Snickster

    PSV Inlet and Outlet Pressure Drop Calculation Question

    Given a length of pipe with a flowing gas with friction. Any pressure (energy) loss due to friction is put back into the fluid if the process is adiabatic. Therefore the velocity increase due to pressure decrease due to friction has to come from the change in enthalpy of the fluid without any...
  20. Snickster

    Relieving temperature PSV

    In adiabatic processes we use T1/p1=Tn/pn (as also API521 says). The above equation is based on a totally gas filled constant volume vessel (no liquid) operating at a given pressure and temperature with a fixed mass and composition. In this case when heat is added from external fire the...

Part and Inventory Search

Back
Top