pedal reciprocating piston_pump[1]

Pedal Reciprocating Piston Powered Pump

Instructor: Ms.Mastewal

Group Member: ID

Wondie Chanie………………….…………..0502760

Tsegaye Chemere ………................................0502706

Wako Abduba………………………………..0502737

Tibebu Dagnew ………………………………0502647

Wondimagegn Wassie……………………..…0502764

Contact:

Mobile: +251932270893

E-mail: [email protected]

INTRODUCTION In our country Ethiopia there is a lot of natural resources like, lakes but we didn't develop our agricultural process in an appropriate way. So we are going to design and develop Manually Operated Pedal Reciprocating Piston Powered Pump.

OBJECTIVE

General Objective: Design manually operated pedal powered pump to demonstrate a functional reciprocating pump in rural people of Ethiopia. To facilitate the local people by providing water for various purposes and to optimize the use of natural resources.

Specific Objective: To design chain and sprocket To design cylinder To design piston and rubber cup To design structure To design shaft Bearing selection

PROBLEM STATEMENT

The introduction of pedal powered reciprocating piston pump must be essential for all rural communities in which electric power is not available. In most rural communities there is no an electric power, so the uses of motor powered pumps are not applicable and fuel powered pumps also not economical for lower level farmers.

APPLICATION AREA Our application area is in south gonder, gumara river near woreta city. And it uses for the irrigation purpose for their agricultural process. And in addition it can operate in all irrigation purpose for any place.

The main components of pedal powered reciprocating piston pump

1. Cylinder 2. Piston

3.Connecting rode 4.Valves

5.Pedal 6. Chain

7. Seal 8. Crank

9. Manifold

WORKING PRINCIPLE

DESIGN ANALYSIS

Design of chain and sprocket: we assume: The driver sprocket rotates at N1 =60rev/min and the driven sprocket rotates at N2 =200rev/min

Then the speed ratio =N2/ N1 =200/60=3 we find that for the roller chain, the number of teeth on the smaller sprocket or pinion (T1) for a velocity ratio of 3 are 25.Number of teeth on the larger sprocket or gear, T2=T1*N2/ N1 =25*(200/60) =83

Design of chain and sprocket con…

From table we find that corresponding to a pinion speed of 200rpm the power transmitted for chain No. 08 is kW per strand. Therefore, a chain No.08 with two strands can be used to transmit the required power. Pitch, p=12.7mm Roller diameter, d=8.51mm Minimum width of roller, w=7.75mm Breaking load =17.8KN

D1=p cosec (180/T) D1 =12.7cosec (180/25) D1 =100mm

D2 =p cosec(180/T1) D2 =12.7 cosec (180/83)

D2 =335mm

L=1514.5mm=1.5145m

K=119 L=K*P=119*12.7 L=1514.5mm=1.5145m

Centre distance between the sprockets,=30p=30*12.7=381mm

In order to accommodate initial sag in the chain, the value of centre distance is reduced by 2 to 5mm

Therefore Correct centre distance x=381-3=378mm We know that the number of chain links

DESIGN OF THE CYLINDER

Material selection: cold rolled stainless steel

Design Specification: Outside cylinder diameter=115mm Cylinder length=200mm Design verification Pressure developed (p)=force on the piston/cross

sectional area of the cylinder Discharge(v)=

(Volume of the cylinder/stroke)*(number of strokes/second)

Output specifications:

Pressure developed=108.24kpa Discharge(Q)=2.07lit/sec

Design of cylinder con…

DESIGN OF PISTON AND RUBBER CUP

Objective: continuous forth and back movement of pistons throughout the cylinders with much better sealing.

Sealing material=rubber cup

The length of the piston must same extent larger than length of the cylinder. Overall height=240mm and the diameter of the piston rod is 20mm taking the clearance as the seal thickness 3mm Piston diameter=112mm

DESIGN OF SHAFT

The diameter of the shaft is determined from the equation: The material for shaft is selected as mild steel its allowable shear stress is: 42Mpa

Design of shaft con…

We get: T=18.9Nm

Then: T=Fr we get F=189N

T=𝜋

16*𝜏*d3 for solid shaft

Calculated value : d=12.8mm

So it is preferable to use diameters greater than this value, let us take standard shaft diameter 15mm

Using this formula: P=2𝜋𝑁𝑇

60

DISIGN OF STRUCTURE

To manufacture the structure first the overall external force and dimensions of all supporting structures must be specified.

We can assume that the operator weight as approximately 60kg and the force applied by the operator by his/her legs 1082 N

α β

Design of structure con…

The free body diagram is shown below

D

C

B

A

For ergonomic comfortability the angle of the seating is α=750 from the horizontal.


Then finally calculating all the force in each members of the structure, these all dimensions which calculating by this method is further important for calculating the dimensions such as diameters.

ΣM=0

ΣF=0

To calculate the force of each members of the structure.

According to American Society of Mechanical Engineers (ASME) code for the design of a fixed load supporting and shaft ,the maximum permissible working stress in tension or compression a hallow steel rod may be taken 84Mpa with allowance.


To calculate the diameters of each members of the structure.

max=𝐹𝑚𝑎𝑥

𝐴

SELECTION OF BEARING

A bearing is a machine element that constrains relative motion between moving parts to only the desired motion. The design of the bearing may, for instance provide for free linear movement of the moving part or for free rotation around a fixed axis or it may prevent a motion by controlling the vectors of load to be supported.

The thrust ball bearings are used for carrying thrust loads exclusively and at speeds below 2000rpm, the load on the bearing is only axial or thrust load, there is no radial load is applied.

fig.0.0 Thrust ball bearing

Selection of bearings con…

Then the total load is given by W=YWA

W=1.3*1313.2N W=1707.16N

In order to select a most suitable ball bearing, first of all, the basic dynamic axial load is calculated. Then it is multiplied by the service factor (KS) to get the design basic dynamic axial load capacity. The service factor is 1.5. Therefore the design dynamic equivalent load should

W=1707.16*1.5 W=2560.74N

We find that for a single thrust ball bearing number 202, the basic dynamic capacity, C=6.30KN =6300N We know that rating life of the bearing in revolutions, L=(c/w)^k*10^6 =(6300/2570.7)^3 =14.7 ∗ 10^6 Revolution …(k=3, for ball bearings) We select life of bearing, in hours, LH=4000 The relationship between the life in revolutions (L) and the life in working hours (LH) is given by N=L/(70*LH)=(14.7*10^6)/(70*4000) N=61.25rpm

CONCLUSION

This project focused on the construction and operation of the reciprocating piston pump. Our achievement is something we term a moderate success. Our project is easy to operate and cost effective (2763.68 birr). By the use of this manually pedal powered pump we can save money and we supply water in irrigation and other agricultural uses.

It is clearly seen that the overall cost for the pump can be using energy efficiency. Therefore we recommend that the over all design should be manufactured and distribute for our agricultural process.

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