Mechanical Engineers

 
Home | Bearing design, manufacture an | Pump engineering | Piping & fluid mechanics engin | Optical systems engineering | Mechanical Seal engineering | Mechanical engineering other t | Mechanical Acoustics/Vibration | Laser engineering
  Position:Home>Pump engineering>Article Content
Discharge head
Source:Internet Author:Unknow Pubdate:2010-06-29  
Chiefkocak (Marine/Ocean) 24 Jun 10 10:45
Gentlemen, I should remember this from school but its been 30 years. I have a 3000 gpm centrifugal pump that the only way to get the head needed is to reduce flow. But this causes many thrust problems with broken shafts. Slowing down the speed of the motor will reduce flow but how much will it reduce discharge head.  

BigInch (Petroleum) 24 Jun 10 13:16
Approximately by H1/rpm1^2 * rpm2^2 "We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying."  Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.liv

CH5OH (Petroleum) 24 Jun 10 13:24

字串1


Volume Capacity
q1 / q2 = (n1 / n2)       

Head or Pressure
dp1 / dp2 = (n1 / n2)^2       

Power
P1 / P2 = (n1 / n2)^3         

Chiefkocak (Marine/Ocean) 24 Jun 10 18:10
Answered the question.
Ship originally installed the 3000 gpm sea water pump with load of close to rated gpm. About a year later AC chiller condenser tube went so they change it to FW cooled. This left
SW pump with little load but close to shutoff head was still needed to cool another AC condenser very high up in the ship. So throttling to get discharge pressure caused shafts to break. 20 years later Port Engineer wants to put a variable speed drive controller on pump. I told him slowing down the pump wouldn't do the trick.  

Artisi (Mechanical) 24 Jun 10 18:11 字串4
How will you "slow" the speed of the motor? If you are running a fixed speed motor the option will be to reduce the impeller diameter.

(Click:
Previous:Two parallel pipes both open to atmosphere   Next:Head rise to Shut off
[Add TO Favorites] [TOP] [PRINT] [CLOCE WINDOWS]  
  Hot Article
·Heat Gain from Pump Motors
·Pump NPSH calculation spreadsh
·ANSI vs. API pump O&M
·KSB feed pump balancing disc d
·Calculating tip speed?
·pump and system curve
·Centrifugal Compressor Curves
·NPSH margin and ANSI/HI 9.6.1
·Liquid ring vacuum pump
·Pump power calculation
·Gerotor Pump Design software
·NPSHa Vertical Turbine Pumps
  Related Articles
·Head rise to Shut off
·Starting Torque - Positive Dis
·Pumps in Parallel
·Waterless Mechanical Seals for
·Pump controllers
·Steam Turbine Operating Cost C
·Back pressure problem in centr
·Pump NPSH calculation spreadsh
·Positive Displacement Pump Rec
·Suction Energy Question
·Does a slow-speed recip need t
·Parallel Pumps Head Loss
MBT SHOES CLEARANCE SALE Cheap LouisVuitton Bags Civil / Environmental Engineers Structural Engineers Aeronautic Engineers Automotive Engineers Chemical Engineers Geotechnical Engineers Industrial / Manufacturing Engineers Materials Engineers Computer Engineers Agricultural Engineers Mechanical Engineers Petroleum Engineers Bioengineers Military Engineers