Boiler feed pump

Fyi : What type of clearance you Mean ? Is it the clearance for rotation (say it Bearing, Seal, Impeller Rings & OD) or Clearance for Bore of the Impeller to the Shaft ( Shrink Fit or Sliding ), some is refer to the OEM but basicly we are refer to API.

Hi,

The most popular pump type is the multi-stage centrifugal and there should never be any internal wear in this machine if clearances have been maintained. The problem arises if the pump has been dismantled for any reason and spacers on the spindle have been misplaced. If this is the case then usually the thing will be jammed solid and further investigation will reveal the trouble. It is even possible to reverse one stage and end up with a severly compromised output!! If the water codition is poor and there are solids present then over time there can be some wear on the impellers causing a loss in pumping efficiency.

Positive displacement pumps will by their very nature have valves,seats and seals and/or piston rings which will wear over time, the rate of deterioration is very much a function of the water quality;also the boiler water treatment regime has an effect on this issue.

Hope this helps.

Hello

Depends on what type of pump you are referring to but generally if the clearances increase, you will start to lose efficiency and pump flow delivery. The higher your operating pressure the greater the reliance on clearance's. Clearance's anywhere else will result in excess leakage or accelerated wear. The clearance setting will be defined by the (OEM) Pump manufacturer within the pumps design and should take into consideration for thermal expansion. Type of pump will also be defined by your temperature, pressure and flow requirement.