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  1. DLANDISSR

    Steam PSV Pipe

    FREAKMEOUT: REFER TO ASME B31.1 APPENDIX II NONMANDATORY RULES FOR THE DESIGN OF SAFETY VALVE INSTALLATIONS The size and length of the discharge pipe from a steam pressure safety valve is critical. As the steam leaves the valve it expands. As it moves down the pipe it continues to expand so...
  2. DLANDISSR

    Equivalent Leak Detection - Hydrostatic vs. Aerostatic (nitrogen)

    Is the question really how much does it leak or is it does it leak? If the question is does it leak then no calculations are needed. Presure up the device with N2 and let it sit for 24hrs. Keep the temperature constant or errors will be introduced. There should be no pressure drop in 24 hrs...
  3. DLANDISSR

    Pressure reduction during contraction

    If we are considering a blocked line that is cooling the pressure will follow the saturation line as the steam cools. The practical answer is: Can the line withstand total vacuum without collapsing, if not, install a vacuum breaker set at a pressure above the collapse pressure.
  4. DLANDISSR

    Crane 410 fittings

    fT is the friction factor in the turbulent region of flow. It is calculated from the Colebook-White equation which is an iteration. The Moody Diagram is derived from the Colebrook-White equation. The Colebrook-White equation uses the Reyonalds Number, the relative roughness.
  5. DLANDISSR

    Duct Insulation

    antonio09: The fact is, if the temperature of the surface of the duct is at or below the dewpoint temperature of the air in the space where the duct is, moisture will condense on the surface of the duct. If you can determine that the duct surface temperature will never be at or below the...
  6. DLANDISSR

    Rotary motion to linear reciprocating motion

    mowrthi: Thread winders usually employ a double thread type drive. The thread goes both ways on the shaft. A follower rides in the thread and at the end of the shaft follows the thread to the return thread. This provides linear movement to distribute the thread evenly on the winder. A fishing...
  7. DLANDISSR

    Flow through existing Pump

    onecolumbyte: Get a pump curve get a test pressure gage and measure the pressure at the suction and at the discharge of the pump'' Measure the voltage and amps at the motor. Look at the pump curve with this data and it should give you a good estimation of the flow. This should be sufficient to...
  8. DLANDISSR

    Flow rates in H2SO4

    JonD71: There is no material which will handle H2SO4 at all concentrations and temperatures. Teflon will handle H2SO4 at all concentrations up to 400F. The only metallic material suitable for H2SO4 is Hastelloy B It is good for 90% to 100% concentration up to 302F(150C). This information is...
  9. DLANDISSR

    1400 Deg. F. Hot Insulated Supports

    NozzleTwister: I have used Thermal Ceramics insulation for up to 2400Deg F. This is like fiber glass blanket insulation but is made of ceramic fibers and a high temperature binder. It will not support the put weight. Graphite blocks could be used which would support the weight. I have used...
  10. DLANDISSR

    Does thrust force appear at the flange of a pump?

    74Elsinore: Without a bellows there is no thrust forces on the pump flange. The thrust forces from the internal pressure are restrained by the pipe wall and flange bolts. The pipe wall and the bolts take the forces in tension and cancel each other. When using a bellows with no bolts to restrain...
  11. DLANDISSR

    Starting Up a Pump

    Milkboy:' The pressure at the mechanical seal at shut off head is not an issue!! I would not start the pump with the discharge valve closed. Start the pump with the valve open. If you want to know the max pump pressure at shut off then close the valve slowly so as to not create any shock...
  12. DLANDISSR

    Temperature control valve for closed loop cooling system

    Dlnnbell: From what you said the aux water is constant flow and the raw water you wish to be variable flow. I assume you wish to use only the raw water needed to offset the temp rise in the aux water system. In this case, the only rational choice is to throttle the raw water flow (since there...
  13. DLANDISSR

    Air Fed Double Diapragm Pumps

    DonnyWane: Right on abcmex! The pressure will always be additive with pumps in series. The problem with diaphragm pumps is that since the pumping is not continuous but cyclic the cycle of each pumps many not be in sync with eachother. The suction pressure of the second pump will not be...
  14. DLANDISSR

    sizing valves

    Duika: You do not give enough information. The usual criteria is to drain the line in some time period. To do this you would need: The main pipe size; Length; elevation difference; fluid density and viscocity; type of valve; drain pipe size, length and geometry. Given the above information...
  15. DLANDISSR

    Pipe Support Span

    Coachk: Grinnell has a table in their "Piping Design and Engineering" book which gives pipe spans for pipe filled with water. The limiting factors are 1500PSI combined bending and sheer stress and max .1"deflection. size/ft are as follow:(since you have spans up to 12")...
  16. DLANDISSR

    Sea Water Service Pipeline, 316L?

    Mufasa: Consider polypropalene. Sea life does not grow on poly. This would solve the clam problem. Also it high density poly is strong and would not be easily damaged. Cement pipe using type V cement is very good for sea water but it is good at growing sea life such as clams, etc. If this is...
  17. DLANDISSR

    Thermal expansion on cooling water pipes

    abcmex: Sliding expansion joints would be a joint like the packing around a valve stem. The pipe will slide through the packing when it expands. When considering this type of expansion joint keep in mind there are pressure forces for which to provide. For example a 40" dia line @ say...
  18. DLANDISSR

    Thermal expansion on cooling water pipes

    abcmex: Why are the ends fixed? Are these flanges to equipment or are they fixed on the pipe rack? How are the take offs to equipment arranged? If the ends are fixed on the pipe rack and not flanged to equipment the ends could be left unfixed axially thereby allowing some movement. If they...
  19. DLANDISSR

    Guys I am looking for some guide

    SAK9: There are two books published by Compass Publications located in La Jolla, CA Tel 619-551-9240 Chemical resistance guide for metals and alloys and Chemical resistance guide for elastomers There may be others.....
  20. DLANDISSR

    Multiple Branch Connections

    Zapster: B31.3 states that branch connections made with standard fittings (like tees, crosses threadolets, weldolets or sockolets) having adequate pressure stregth do not need to be calculated. There is no restriction on the number of connections around the perimeter of the main pipe. The...

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