Design and Fabrication of Multi Speed Centrifugal Pump
1. DESIGN AND FABRICATION OF MULTI SPEED CENTRIFUGAL PUMP
Submitted By
M. Lakshmi Narayanan (6613201016)
Rakesh Yonjan (6613201034)
N. Ramaswamy (6613201035)
Raushan Kumar Sah (6613201038)
Under the Guidance of
Mr. J. Selvamani
Assistant Professor
Department of Mechanical Engineering
FACULTY OF ENGINEERING AND TECHNOLOGY
DEPARTMENT OF MECHANICAL ENGINEERING
PRIST UNIVERSITY
THANJAVURE - 613403
12/05/2017
2. ABSTRACT
This project is about obtaining various discharges from centrifugal pump.
Here we are going to modify pulley to obtain so.
The pump and motor will be connected with round belt and cone shaped
pulley.
The belt can be moved from one dimension of the pulley to another with the
help of lead screw.
Our main focus is on obtaining variable discharge while the system is on
running condition.
The project is designed with the hope that it is very much economical and
helps to obtain variable discharge with variable speed.
3. INTRODUCTION
In this project we are using electric motor of 1440 rpm.
Round belt and cone shaped pulley system is used.
Through this mechanism we can be able to vary speed with the help of cone shaped
pulley and round belt.
Here we are going to design and fabricate the multi speed centrifugal pump for the
different discharges.
This equipment has been mainly developed for variable speed working mechanism.
This project is made with pre-planning, that it provides flexibility in operation.
This innovation is more desirable and economical.
4. LITERATURE REVIEW
MOTOR
Michael Faraday
The principle of conversion of electrical energy into mechanical energy by
electromagnetic means was demonstrated by the British scientist Michael Faraday in 1821.
Hungarian Ányos Jedlik
In 1855 Jedlik built a device using "electromagnetic self-rotors" principles that was
capable of useful work.
Zenobe Gramme
The modern DC motor was invented by accident in 1873, when Zenobe Gramme
connected the dynamo he had invented to a second similar unit, driving it as a motor.
Nikola Tesla
In 1888 Nikola Tesla invented the first practicable AC motor and with it the polyphase
power transmission system. Tesla continued his work on the AC motor in the years to follow
at the Westinghouse company.
5. CENTRIFUGAL PUMP
Reti
According to Reti, the first machine that could be characterized as a centrifugal
pump was a mud lifting machine which appeared as early as 1475 in a treatise by the
Italian Renaissance engineer Francesco di Giorgio Martini.
Denis Papin
True centrifugal pumps were not developed until the late 17th century,
when Denis Papin built one using straight vanes.
John Appold
The curved vane was introduced by British inventor John Appold in 1851.
6. PULLEY
Plutarch
• It is not recorded when or by whom the pulley was first developed.
• It is believed however that Archimides developed the first documented block and
tackle pulley system, as recorded by Plutarch.
• Putarch reported that Archimides moved an entire warship, laden with men, using
compound pulleys and his own strength.
7. Methodology Flow Chart
Data Collection
Dimensional
Analysis
Material Selection
Calculations
Designs
Analysis
Operations on raw
materials
Assembly of parts
Paint on required
parts
9. WORKING PRINCIPLE
Multi speed centrifugal pump is more specially used to reduce the power
consumption and regulate flow rate whenever required.
It is simple in construction as motor drive the centrifugal pump through round belt
and cone shaped pulley.
Here screw rod is used, whenever flow rate and pressure are required to change, it
can be changed by changing belt to various dimensions of pulley.
Therefore, Multi Speed centrifugal pump is most useful in domestic and industrial
purposes.
10. CALCULATIONS
KNOWN DIMENSIONS:
Diameter of large end of pulley 1 (d1 )= 115mm
Diameter of small end of pulley 2 (d2 )=50 mm
Center distance of the pulley (x) = 235mm
Length of the belt,lb
The length of the belt can be calculated as
Lb =
π
2
(d1 + d2 ) + 2x +
(d1
−
− d2)2
4𝑥
(Ref. from “Text Book of Machine Design”)
Lb =
π
2
(115 + 50 ) + 2(235) +
(115 −
−
50)2
4(235)
= 259.18+470+4.49
Length of the belt,lb= 733.67mm
11. Speed of second pulley connected to centrifugal pump based on change in diameter
i) When belt is on large end of pulley 2 and small end of pulley 1
D1 = 50mm (Pulley 1) D2 = 115mm (Pulley 2)
N1 = 1440/9=160 RPM N2= ?
D1/D2 = N2/N1 (Belt and Pulley velocity ratio from Text Book of M.D.)
50/115 = N2/160
N2 = 69.56RPM
Therefore pump speed will be 69.56rpm approx.
12. ii) When belt is on small end of pulley 2 and large end of pulley 1
D1 = 115mm (Pulley 1) D2 = 50mm (Pulley 2)
N1 = 160RPM N2= ?
D1/D2 = N2/N1 (Belt and Pulley velocity ratio from Text Book of M.D.)
115/50 = N2/160
N2 = 368 rpm
Therefore pump speed will be 368 rpm approx.
13. DESIGN CALCULATION FOR WATER PUMP
Diameter of discharge end of pump (D) =19.05 mm = 0.01905m
Q = discharge (m3/s)
i) When belt is on large end of pulley 2 and small end of pulley 1
We have N = 69.56x2=139.12 rpm
{Speed of shaft of pump is multiplied by 2, as gear ratio is 1:2}
So,
Velocity of shaft of Pump
V = πdN/60
= (π x 0.019 x139.12)/60
= 0.138 m/s
14. Here,
Area (a) = {(3.14/4)*(D2)}
= (.785x.0.0192)
= 2.83 x 10-4m2
Discharge Q = a x v
= 2.83 x 10-4 x0.138
Q = 3.91x10-3 m3/s
We know
1 m3/s = 3600000 lph
For, Q = 3.91x10-3 m3/s
3.91x10-3 m3/s = 140.59 lph
Lph = litres per hour
Therefore, Discharge (Q) =140.59 lph
15. ii) When belt is on small end of pulley 2 and large end of pulley 1
We have
Speed of shaft of Pump (N) = 368 rpm
So,
Velocity of shaft of Pump
V = πdN/60
= (π x 0.019 x368)/60
= 0.732 m/s
Here,
Area (a) = {(3.14/4)*(D2)}
= (.785x.0.0192)
= 2.83 x 10-4 m2
16. So,
Discharge Q = a x v
= 2.83 x 10-4 x 0.732
Q = 2.072x10-4 m3/s
We know
1 m3/s = 3600000 lph
So,
For, Q= 2.072x10-4 m3/s
2.072x10-4 m3/s = 745.76 lph
DISCHARGE (Q) = 745.76 lph
17. MERITS AND DEMERITS
MERITS
• Easy to implement
• Easy to operate
• Low cost
• Variable speed obtainable
DEMERITS
• Need proper maintenance
• Chances of belt to slip
19. CONCLUSION
• This project is made with pre planning, that it provides flexibility in operation. This
innovation has made the more desirable and economical.
• The project is designed with the hope that it is very much economical and helps to
obtain variable rate of discharge in variable speed.
• This project helped us to know the periodic steps in completing a project work. Thus
we have completed the project successfully.
• .
20. FUTURE ENHANCEMENT
• CVT method can be installed for automation.
• Impeller and casing of the pump can be changed for variable discharged.
• High rpm motor can be used.
• Belt and pulley quality can be enhanced for longer duration of operation with
minimum maintenance