Bmeia Hydram Pump Design

1. BMEIA HYDRAM PUMP DESIGN
Hydram Pump Part Volume Calculation
David Effa and Dr. Abiy Awoke
WCDE-00088-06
Revision 100112
David M. Effa works in the Waterloo Cases in Design Engineering Group (WCDE) in the Faculty of Engineering at the University of Waterloo. He
prepared this design case study for classroom use. The author does not intend to illustrate either effective or ineffective handling of an engineering
situation. The author may have disguised certain names and other identifying information to protect confidentiality.
The Waterloo Cases in Design Engineering Group prohibits any form of reproduction, storage or transmittal of this document without its written
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Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada, N2L 3G1. Copyright © 2008-2009, David M. Effa.
Used by the University of Waterloo with permission.
Introduction
Basic Metal and Engineering Industries Agency (BMEIA) proposed to supply water for a small village
(population of about 500 people) from a stream of water using a Hydram pump. The Hydram pump
components must be designed according to the results generated from a site survey and an environmental
assessment. The Hydram pump has to pump water at 80 litres per minute to a height 5 times that of the
distance from the source to the pump [1]. The amount of water pumped to the required destination depends on
the quantity of water available from the source and a number of design factors including the volume of the air
vessel, main body parts and other connections. Most of the Hydram pump parts are constructed from cast iron,
as shown in Figure 1, in order to withstand vibration and cycling load during the pumping process. It is
required to compute the inside volume of the pump parts and estimate the amount of cast iron needed for
fabrication. These information will help to optimize the desired performance of the pump and help estimate
material cost as well.
Figure 1- Fabricated Hydram pump (Air vessel and Main body parts)

2. BMEIA Hydram Pump DesignWCDE-00088-06
Air Vessel Volume Calculation
The air vessel is a vital component of the Hydram pump and is visually its main characteristic. Without it, the
water coming through the delivery valve would have a great velocity and too much head losses would be
created. With the air vessel, the water is slowed down because the air inside the air vessel acts like a spring.
The volume of the air vessel, manufactured by BMEIA, ranges between 0.5 m3
and 2 m3
depending on the
water source and water requirements. The air vessel is axially symmetric about the vertical axis, as shown in
Figure 2 (b). The top section is an elliptical sphere with a flange and the bottom section is a cylinder with
amounted connecting parts. Figure 2 (a) and (b) shows a section view of the air vessel and the approximated
inside profile respectively. The basic design parameter used to determine the inside volume is shown in Figure
2 (b) and detail dimension of the air vessel is given in Appendix A.
The inside volume of air vessel needs to be estimated during the preliminary design stage since it determines
the amount of water that can be pumped per unit time. BMEIA engineers used CAD software to compute the
volume and amount of material required as part of their design process. After developing the 3D model a
Mass Properties dialog box, similar to Appendix B, displays all geometric details of the given 3D model,
including its volume. However, this method is a time consuming process since the designer needs to develop a
CAD model to determine these parameters. In the following exercise calculate the volume of the air vessel
shown in Fig. 2 using a triple integral in circular cylinder coordinates evaluated using MathCAD. Compare
your results with the value from the SolidWorks® model shown in Appendix B.
esten
(a) (b)
Figure 2:- Hydram pump air vessel (a) section view (b) inverted air vessel inside profile and design parameters

3. BMEIA Hydram Pump DesignWCDE-00088-06
References
[1] David Effa and Dr. Abiy Awoke, “BMEIA Hydram Pump Design”, WCDE 00089-01, Waterloo Cases in
Design Engineering, April 2010
[2] David Effa and Dr. Abiy Awoke, “BMEIA Hydram Pump Design”, WCDE 00089-02, Waterloo Cases in
Design Engineering, April 2010
[3] Lorenz, H.: Theorie des hydraulischen Widders. Z. VDI Vol. 54 (1910) pp. 88/90.

4. 4
WCDE-00088-06
Appendix A - Air Vessel Detail Design

5. 5
WCDE-00088-06 BMEIA HYDRAM WATER PUMP DESIGN
Appendix B - SolidWork Air Vessel 3D model Mass Properties Dialog Box