Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
(OP)
1Would too high differential pressure could damage the internal gear pd pump componenta range around 10 bars above ?
Rotor, idler, bushing and so on
2.As some of commons types of pump casing construction are
Cast iron, steel, stainless steel, carbon steel:
How to determine the suitability of material compitability of different types of fluid ? I hope anyone with commons liquid types are able to share their casing's material application
Rotor, idler, bushing and so on
2.As some of commons types of pump casing construction are
Cast iron, steel, stainless steel, carbon steel:
How to determine the suitability of material compitability of different types of fluid ? I hope anyone with commons liquid types are able to share their casing's material application





RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
An important requirement for gear pump systems is to include a pressure relief valve in the discharge piping (fairly close to the pump itself) to relieve pressure back to the storage tank or other liquid supply source, when downstream valves are shut off. Some gear pumps include a built-in pressure relief valve which will provide the same critical pressure relief but only for very short time periods. This is because the built-in pressure relief valves are internal to the gear pump and simply recirculate the liquid inside the gear pump itself. Recirculation inside the gear pump for other than very short time periods will cause the liquid to build heat quickly and will eventually ruin seals, packings or other key gear pump components.
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
My doubts in PD pumps :
How the suction pressure is developed and sometimes we are getting - (negative) suction pressure. How suction pressure usually is calculated
On the contrary of suction pressure, discharge pressure is usually determined by process, how the process able to determined this on the design stage of their system.
If the discharge pipe is very long 1 to 2 km and 4 inch pipe, does this determined the discharge prrssure required or the diff pressure
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
A positive displacement pump moves a set volume of liquid. Pressure is created as the liquid is forced through the pump discharge into the system. The pump converts energy into pressure. Positive-displacement pump create flow and discharge pressure is created by system's response to flow (ie: discharge pressure = discharge line total backpressure at pump outlet flange).
Note that a rotary unit will continue to pump if there’s a downstream blockage. So, rotary systems require some type of safety pressure-relief valve at or immediately downstream of the pump to protect against over-pressure. It doesn't matter what the discharge pressure is; the pump is going to transfer that volume regardless, i.e. "positive displacement". If discharge valve is closed, then either the motor will shut down or something will go Kablooey.
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
Blockage on the discharge. So most of over pressure basicly due to blockage ? Isnt that if we running the motor at higher speed, the pressure would increase ?
Would we able to throttle the discharge valve to calibrate the discharge pressure in pd pump, so small opening would we get higher discharge pressure. i wonder how we could simulate the flow and discharge by using throttling methods
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
Do not throttle the suction. Adjust the discharge pressure with a valve to be 5 bar above whatever the suction pressure is if you want to create a 5-bar differential across the pump.
Ted
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
I would like to know fpr hydrostatic test, it is advisable to hydro pressure test at max allowable working pressure of the pump and adding 50 % more assuming maximum is 25 bars and 32.5 bar run hydro test.
Curious if api 676 has this requirement ?
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
The pressure is the system is raised to the hydrostatic test pressure, the pump is disconnected, and the pressure is then monitored for a set period of time.
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
Ted
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
http://www.cityoffullerton.com/civicax/filebank/bl...
The system is filled with fluid and then the test uses a small pump to raise the pressure to the desired test pressure.
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)
bmw381be
Question such as " Curious if api 676 has this requirement ?"
You are expecting other to feed you instead of trying to find out your self for such a simple matter.
RE: Internal gear Positive displacement Pump ( Harmful high Diff P and construction)