Centrifugal Pumps: Basics Concepts of Operation, Maintenance, and Troubleshooting, Part I
By: Mukesh Sahdev, Associate Content Writer
Presented at The Chemical Engineers’ Resource Page, www.cheresources.com
Centrifugal Pumps: Basic Concepts of Operation, Maintenance, and
Troubleshooting (Part- I)
Introduction
The operating manual of any centrifugal pump often starts with a general statement,
“Your centrifugal pump will give you completely trouble free and satisfactory service only
on the condition that it is installed and operated with due care and is properly maintained.”
Despite all the care in operation and maintenance, engineers often face the statement
“the pump has failed i.e. it can no longer be kept in service”. Inability to deliver the desired
flow and head is just one of the most common conditions for taking a pump out of service.
There are other many conditions in which a pump, despite suffering no loss in flow or head,
is considered to have failed and has to be pulled out of service as soon as possible. These
include seal related problems (leakages, loss of flushing, cooling, quenching systems, etc),
pump and motor bearings related problems (loss of lubrication, cooling, contamination of
oil, abnormal noise, etc), leakages from pump casing, very high noise and vibration levels,
or driver (motor or turbine) related problems.
The list of pump failure conditions mentioned above is neither exhaustive nor are the
conditions mutually exclusive. Often the root causes of failure are the same but the
symptoms are different. A little care when first symptoms of a problem appear can save the
pumps from permanent failures. Thus the most important task in such situations is to find
out whether the pump has failed mechanically or if there is some process deficiency, or
both. Many times when the pumps are sent to the workshop, the maintenance people do not
find anything wrong on disassembling it. Thus the decision to pull a pump out of service for
maintenance / repair shou