For avoiding cavity what should be NPSH?




Answers were Sorted based on User's Feedback



For avoiding cavity what should be NPSH?..

Answer / mohamed

NPSH Available should be more than The Rquired NPSH.
I mean that the pressure at the suction eye of the impeller
should be more than the saturated pressure for the pumped
liquid otherwise the pumped liquid will start to evaporate
and cavitation problems will start.
i will mension here some reasons for cavitation:
- pump selection is not correct
-suction tank is not in a proper elevation.
- isolation valves are partially closed
- mesh size of pump strainer is not correct
- pump strainer is partially blocked
- the system is not vented in aproper way .
- tempertaure of pumoed liquid is deviated form normal
values.
still many reasons are there , but finally you should keep
the pressure at pump suction more than saturated pressur.

Is This Answer Correct ?    12 Yes 1 No

For avoiding cavity what should be NPSH?..

Answer / mazher

For avoiding cavitation NPSH(Available) should be always
greater than NPSH(Required).

Is This Answer Correct ?    7 Yes 1 No

For avoiding cavity what should be NPSH?..

Answer / rajesh

Cavitation takes place when liquid pressure falls below its
Vapour Pressure forming bubbles of liquid.
To avoid cavitation (NPSH)available > (NPSH)required.
We know that...
NPSH is Net Positive Suction Head.
Therefore,
NPSH = (H)atm - (H)vapour - (H) manometric
the above equation must come Positive value to avoid
cavitation!!!

Is This Answer Correct ?    1 Yes 0 No



Post New Answer



More Mechanical Engineering Interview Questions

whether supercharger is used in si engine or not?if it is used then at which destination?

1 Answers  


distance between the power generation and the distribution to the application is fixed or vary

0 Answers  


What is the cold side of the refrigeration system?

1 Answers   RRB,


what is the required force to bend 2.5 MS sheet in 90 degrees and what is the formula to calculate the same?

0 Answers   Voltas,


As per api 650 code for new ss tank fabrication,in bottom plate bulge is acceptable? How many bulge acceptable for api 650?

0 Answers   Hyundai,






In d thermal power plant why D/A placed on height.

4 Answers  


what are the supports using in critial pipe line and what are the type of support using oil&gas, power plant.

2 Answers  


Upper piston ring is compression ring?

8 Answers   BEL,


Methods to dry up wet induction motors?

0 Answers   RRB,


hi dear friends i have applied RRB exams SE so i need previous year question papers please send to my mail id santhu.hpt@gmail.com

0 Answers  


why transformer required and why not voltage directly supply from power generation to the applications

3 Answers  


what is effect of silica in steam boiler

1 Answers   Diversey,






Categories
  • Civil Engineering Interview Questions Civil Engineering (4640)
  • Mechanical Engineering Interview Questions Mechanical Engineering (3705)
  • Electrical Engineering Interview Questions Electrical Engineering (15780)
  • Electronics Communications Interview Questions Electronics Communications (2638)
  • Chemical Engineering Interview Questions Chemical Engineering (762)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (79)
  • Bio Engineering Interview Questions Bio Engineering (30)
  • Metallurgy Interview Questions Metallurgy (95)
  • Industrial Engineering Interview Questions Industrial Engineering (199)
  • Instrumentation Interview Questions Instrumentation (2882)
  • Automobile Engineering Interview Questions Automobile Engineering (171)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (41)
  • Marine Engineering Interview Questions Marine Engineering (62)
  • Power Plant Engineering Interview Questions Power Plant Engineering (170)
  • Engineering AllOther Interview Questions Engineering AllOther (1335)