Table of Contents
POSITIVE DISPLACEMENT RECIPROCATING PUMP FUNDAMENTALS—
POWER AND DIRECT ACTING TYPES
Herbert H. Tackett, Jr.
Reciprocating Product Manager
James A. Cripe
Senior Reciprocating Product Engineer
Union Pump Company; A Textron Company
Battle Creek, Michigan
Director of Product Development - Aftermarket
Union Pump, A Textron Company
A Trading Division of David Brown Engineering, Limited
Herbert H. Tackett, Jr., is Reciprocating
This tutorial is intended to provide an understanding of the
Product Manager for Union Pump Company,
fundamental principles of positive displacement reciprocating
in Battle Creek, Michigan. He has 39 years
pumps of both power and direct acting types. Topics include:
of experience in the design, application, and
maintenance of reciprocating power and
A definition and overview of the pump types—Including the
direct acting pumps. Prior to Mr. Tackett’s
differences between single acting and double acting pumps, how
current position in Aftermarket Product
both types work, where they are used, and how they are applied.
Development, he served as R&D Engineer,
Component options—Covers aspects of valve designs and when
Field Service Engineer, and new equipment
they should be used; describes the various stuffing box designs
order Engineer, in addition to several
available with specific reference to their function and application,
positions in Reciprocating Pump Sales and Marketing. He has been
and points out the differences between plungers and pistons and
a member of ASME since 1991.
their selection criteria.
Specification criteria and methodology—What application
James A. Cripe currently is a Senior
information is needed by pump suppliers to correctly size and
Reciprocating Product Engineer assigned
supply appropriate equipment?
to the New Product Development Team for
Additional topics—Volumetric and mechanical efficiency, net
Union Pump Company, in Battle Creek,
positive suction head available and required, plus piping systems
Michigan. He has more than 30 years of
(suction and discharge) basic principles for reciprocating pumps,
experience in design, application, and
which are different from those of centrifugal machines.
manufacture of reciprocating power and
direct acting type pumps. Prior to his
current position, he served as new
Although reciprocating pumps have been around for over 2000
equipment order engineer, R&D engineer,
years, they did not gain wide popularity until 1840 when Henry R.
special projects Engineer, and Nuclear Engineer.
Worthington invented the steam pump. These early, simple machines
Mr. Cripe has a B.S. degree (Mechanical Engineer) and has
have evolved into the advanced reciprocating products seen today in
been a member of ASME since 1981.
many industries. During the last 30 years technology improvements
have allowed centrifugal and other pump types to become more
popular, and reciprocating machines have become somewhat
Gary Dyson is Head of Product
marginalized. That being said, there are still many applications
Development - Aftermarket, with Union
where reciprocating pumps outperform their centrifugal counterparts.
Pump Company, in Battle Creek, Michigan.
The dominance of these alternative pump types has lead to a
He held senior positions in Aftermarket
knowledge gap for positive displacement machines. However, the
Engineering, Hydraulic Design, and New
positive displacement reciprocating pump is still a vital part of
Equipment Design prior to his current
industry and will remain in use for the foreseeable future.
leadership role. Dr. Dyson previously held
engineering positions with Weir, Mather,
It is important for those who specify, engineer, and use the
and Platt Pumps. He is the author of five
pumps to have a fundamental knowledge of the principles of these
papers on modern methods in pump design
machines, what they can do, and when to use them. This tutorial is
and is spearheading Union Pump’s research into aftermarket
intended to provide a reawakening of interest in these important
solutions on pump emissions reduction.
pumps and a forum for education and discussion.