made and how shop resources are being impacted due to pump
repairs. PIP recommends MTBF metrics to be calculated for
different classes of pumps, such as hot pumps, reciprocating
pumps, etc. as a means of improving its usefulness.
Working with External Suppliers
Machinery reliability metrics have been receiving increasing
attention recently because of the growing interest in improving operating plant profits through reliability improvement
programs. This first began internally, but has extended outside
the process plant confines. Now external suppliers are offering
reliability improvement programs at a fixed annual cost. I am
aware of several mechanical seal programs that have delivered
on their promises to improve plantwide reliability at a fixed
fee.
For these types of programs to
be successful, participating operating
plants must be willing and able to provide meaningful reliability metrics to
external suppliers of seals, new pumps,
pump repairs, etc. To my knowledge,
pump MTBR calculations are the
only practical means available to track
machinery performance in a plant
environment.
As key players in reliability joint
ventures, external suppliers need to
understand the limitations of the maintenance data collection process and the
inherent inaccuracies in the MTBR
value provided to them. While this
metric may be considered by some to
be flawed and somewhat unscientific, if
calculated consistently, it can provide a
reasonable benchmark for gauging reliability gains.
Both pump owners and external
suppliers need to continue working
together to refine the PIP MTBR standard so that it is better understood and
becomes widely accepted. The present
standard is not perfect, but it’s a good
start!
P&S
Robert X. Perez, the website editor for
PumpCalcs.com, has over 25 years
of rotating equipment experience in
the petrochemical industry, holds a
BSME from Texas A&M University in College Station, a MSME
degree from the University of Texas
at Austin, a Texas PE license, and is
an adjunct professor at Texas A&M
University-Corpus Christi, teaching
the Engineering Technology Rotating Equipment course. He can be
reached at rxperez@pumpcalcs.com.
