Hi,
(1) As per NACE MR0175, if the partial pressure of H2S is 15 psi or more, then it calls for applying the NACE requirements. In essence, this calls for including impact strength tests. Hence, along with suction/discharge pressure for the MPP, you need to indicate the percentage of H2S in...
Hi,
No doubt the velocity will increase impacting head losses in the system thereof (V^2/2g). However, this increment is marginal and can be ignored safely. Absolutely no issues with that in terms of pump performance.
Yes, there is a limit on minimum pump efficiency that is indirectly set for the API 610 pumps. As per API 610, the minimum motor rating shall be 4 kW. Hence, if the pump efficiency drops to a value leading to lowering of pump rated power and subsequently lowering motor rating less than 4 kW...
Although Fire Water pump is near sea, it may be fed with clean clear water (free of chlorides etc.). In that case, Cast Iron can be used as material of construction for these pumps.
If it is pumping sea water (untreated), you need to use Super Duplex Stainless Steel.
Anti reverse rotation (paul-and-ratchet mechanism) is generally a common requirement for Vertical pumps. This is because during emergency trip of the pump, there is an amount of fluid that would be accumulated in between the pump delivery flange and the non-return valve, which would flow back to...
Hi,
(1) Diaphragm pumps can be with or without external couplings. In that case, rigid couplings are used and alignment is critical.
Further, flange motors (vertical) are usually used for such pumps. In case of flanged motor driven equipment, motors need to be dislodged first before pump can be...
Hi,
(1) Fire Water pumps, either diesel engine driven or electric motor driven has to deliver at least 150% of rated flow. This is as per NFPA 20. As such, this automatically covers end of curve flow in all practical sense.
(2) In case of Diesel Engines in FW service, the inbuilt fuel tank...
Rotary air compressors operating in 1 operation + 1 standby configuration employs a load/unload valve being connected in parallel at the suction piping side. They help deal with frequent load/unload without adversely impacting compressor or motor from frequent start/stop.
Remember motors are...
[1] Pressure developed by a compressor is not always done in single casing. For high pressure applications, we may need two or more casings which are connected in series. One of these casings develop less pressure as compared to the other, and thus is called LP (Low Pressure) casing, while the...
As per NACE, Stainless Steel is not a suitable material when the partial pressure of H2S in fluid stream is in excess of 15 psig. As such, in your case, SS316 is not suitable for your application.
In your application, you need Alloy material such as Alloy 20.
Hi,
Slow roll of Steam Turbine can be as low as 5% of the Max Rated Speed, if that's what you are looking for. This speed is dictated by machine's lubrication system capability.
Lube oil (LO) System for Steam Turbine is usually equipped with shaft driven main LO pump along with...
Hi,
Regarding your two questions :
1. Solid containing pumped liquid is an abrasive service, for which a shorter length of shaft seal is required in view of reliability considerations. F-B seals requires the longest, followed by F-F seals and then B-B (which requires the least of the shaft...
Hi Arshad,
In order to determine reference pressure, you need to select the type of control system (Differential Pressure based system / Flow control-based system).
Differential Pressure based system --> reference pressure shall be from direct drilling on Shaft end seals (process side)
Flow...
Hi Roger,
Regarding your questions, please note :
(1) The orifice at the CSV is incorrectly sized, for which the back-pressure on the sealing system is higher than required leading to gas accumulation and eventually over-pressurization of the sealing chamber. Orifice size is a function of the...
Hi,
Regarding your two questions :
1. Solid containing pumped liquid is an abrasive service, for which a shorter length of shaft seal is required in view of reliability considerations. F-B seals requires the longest, followed by F-F seals and then B-B (which requires the least of the shaft...
Hi Rahul,
Sorry to state that your question is not quite correct.
There is no such thing as "cast iron pump with 300# rating flange". I guess you are referring to normal centrifugal pumps wherein the pump nozzles are integrally cast with the pump body. In that case, cast iron flange rating is...
I suspect you are dealing with volumes of air but with small pressure rise. Essentially this is not a compressor but rather a blower (large volume air handling equipment) OR a fan (small volume air handling equipment). Because of the small pressure rise, the density difference across the...
