A foundation will be designed for a large new vertical turbine pump with a suction can. Given the size of the proposed pump, I suspect the foundation will take the form of a thick walled concrete cylinder approximately 6ft in diameter x 15ft deep in the ground. Since this is near the Gulf...
At the relatively low pressures involved, consider bumping the design pressure of the shell to match the tubeside pressure (or 10/13 of the tubeside pressure per API). If the exchanger is not a very large diameter, then the incremental cost may not be significant (maybe less than the...
For an ASME vessel. As a first pass, you should use nominal thickness minus corrosion allowance (C.A.). If the nozzle neck is made of pipe, you can typically take mill tolerance(12.5%) off the nominal thickness before subtracting the C.A., as it would have been allowed for during the design...
Depending on the size of the components, your total header volume may be equal-to or more than your receiver volume. If there are users upstream of the meter (cracked open bleeders, dryer purge, leaks, etc), then the receiver may supply these, while the expanding header supplies the units. This...
Our refinery has always used solid metal gaskets to seal fin fan shoulder plugs. (threaded plugs in header boxes of air cooled exchangers) Proper preparation of the machined sealing surface has always been a problem when reassembling these exchangers.
I would like to look at going with grooved...
It sounds like air entrainment. I agree that NPSH or mechanical problems would show up in vibration or unsteady pressure readings.
Suspect that air may be trapped in any high points in the line such as the hose corregations. (especially if hose is arched/pocketed) If so, this air could be...
The cases this could be applied would be rare, and I am not sure if there would be any benefit. A discharge throttling valve would be a more reliable set-up.
*The amount of excess suction pressure would need to equal a significant chunk of the pump's differential head to allow control.
*Pump...
Many vertical canned pumps have zero NPSH requirment measured from the inlet flange. The depth of the flooded can gives additional NPSH to the impeller eye.
If this is the case you may be OK, but I would still prefer some margin (liquid level above inlet flange) for reliability.
You cannot increase the size of the piping, and the PVC probably limits the amount of pressure you can use to push more water through.
It sounds like you need to feed the existing system from multiple locations. An expansion tank (or a second pump) at the far end of the piping system would...
Dascav,
If I understand your system correctly, (additional pump head available, bled thru a restriction valve; motor trips as valve is opened more) the bypass line will not give you extra capacity; it will just send some of the capacity you have going forward now, back to the suction.
Two ways...
The stated speed of 5800 rpm seems very high for a contact seal like a carbon ring. (heat damage from friction?)
Is this speed comparable to other fans in your facility?
I have heard this used for Recycle compressors, where the system makes a loop back to the suction.
While running, the compressor will have a high discharge pressure, which drops thru some equipment, back to a lower pressure at the suction.
If the compressor trips off, the pressure will settle...
Bingopin brings up a valuable point. Cooling the seal faces with steam quench is not always necessary, and wet steam will do more harm than good.
A nitrogen quench will not cool as well as steam, but will keep oxygen away from the faces to prevent coking.
You may not have a problem with gas pockets depending on the type of pump.
The pump Centerline should be kept at or above the suction line, with suction pipe flat or continuously rising. This will be easy to do with an end-suction pump, but not with some types of between bearing pumps.
If it is like the ones I'm used to, your seal oil trap should have a restriction orifice on its vent that will limit the gas loss. There should be little or no pressure drop across the inner laby and the trap will run at suction/seal pressure.
