Reciprocating Pump with Air vessel presentation

24

Click here to load reader

Transcript of Reciprocating Pump with Air vessel presentation

Page 1: Reciprocating Pump with Air vessel presentation

WELCOME

Page 2: Reciprocating Pump with Air vessel presentation

V B POLYTECHNIC NAME: PATIL KRUNAL R.

EN.NO: 106550319004

SEMESTER: 3rd

BRANCH: MECHANICAL/101

SUB. NAME: FMHM

SENINAR TOPIC: A seminar on Heat Pump

GUIDED BY: HIREN PATEL (L.M.E.)

Page 3: Reciprocating Pump with Air vessel presentation

A seminar on RECIPROCATING PUMP

WITH AIR VESSEL

Page 4: Reciprocating Pump with Air vessel presentation

Introduction

Page 5: Reciprocating Pump with Air vessel presentation

Reciprocating pump is one kind of the positive displacement pumps and it known (positive displacement pump) because in it liquid is pushed out of the cylinder by the actual displacement of the piston or plunger.

Page 6: Reciprocating Pump with Air vessel presentation

MAIN PARTS OF RECIPROCATING PUMP

Page 7: Reciprocating Pump with Air vessel presentation

(1)Cylinder : It is made of cast iron or steel alloy. The piston reciprocates inside the cylinder. The movement of piston is obtained by a connecting rod which connects piston and rotating crank.

(2)Suction pipe: It connects the source of water and cylinder, the water is sucked.

(3)Delivery pipe: Water sucked by pump is discharged into delivery pipe.

(4)Suction valve: It adjusts the flow from the suction pipe into delivery pipe.

(5)Delivery valve: It admits the flow from the cylinder in to delivery pipe.

(6)Air vessel: It is a cast iron closed chamber having an opening at its pass through which the water flows into vessel.

Page 8: Reciprocating Pump with Air vessel presentation

WORKING

FIGURE 2

Page 9: Reciprocating Pump with Air vessel presentation

During the suction stroke the piston moves left thus creating vacuum in the Cylinder.

This vacuum causes the suction valve to open and water enters the Cylinder.

During the delivery stroke the piston moves towards right. This increasing pressure in the cylinder causes the suction valve to close and delivery to open and water is forced in the delivery pipe.

The air vessel is used to get uniform discharge.

Page 10: Reciprocating Pump with Air vessel presentation

PURPOSE OF AIR VESSELS To obtain liquid at uniform discharge. Due to air vessel acceleration head and

friction head decreases The work required to overcome the

friction resistance in suction and delivery pipe decreases.

Reciprocating pump can run at high speed without flow separation.

Page 11: Reciprocating Pump with Air vessel presentation

HEADS OF RECIPROCATING PUMP

1. Suction head (Hs)2. Delivery head (Hd)3. Frictional head (Hf)4. Total head (H)

Page 12: Reciprocating Pump with Air vessel presentation

(1) Suction head: it is a vertical height from the surface of liquid in sump to the center of pump as shown in fig 1 & 2.

(2) Delivery head: it is the height to which the liquid is lifted above the center of cylinder.

(3) Frictional head: it is defined as the losses of head due to frictional resistance.

Suction pipe frictional head losses:

Page 13: Reciprocating Pump with Air vessel presentation

Delivery pipe frictional head losses:

Where, f= frictional factorl= length of pipe (ls & ld)V= velocity of liquid (Vs & Vd)d= diameter of pipe (ds & dd)

(4) Total head: theoretically, total head is sum of the suction head, delivery head and frictional head losses in pipe.

Total head, h= + + +

Page 14: Reciprocating Pump with Air vessel presentation

TYPES OF RECIPROCATING PUMP

There are main two types:1. Single acting2. Double acting They can also be classified as under:1. Simplex (one cylinder)2. Duplex (two cylinder)3. Triplex (three cylinder)4. Quadruplex (four cylinder)

Page 15: Reciprocating Pump with Air vessel presentation

Single acting pump

In a single acting pump, the backward stroke of the piston causes a suction which pulls in liquid through the inlet valve. (The same suction action keeps the discharge valve closed). On the forward stroke, the increase in pressure generated by the piston, closes the inlet valve and opens the discharge valve. The liquid is displaced into the discharge system.

Page 16: Reciprocating Pump with Air vessel presentation

Double acting pump

This type of pump operates in exactly the same way as the single acting with respect to its action. The difference is, that the cylinder has inlet and outlet ports at EACH END OF THE CYLINDER. As the piston moves forward, liquid is being drawn into the cylinder at the back end while, at the front end, liquid is being discharged. When the piston direction is reversed, the sequence is reversed.

Page 17: Reciprocating Pump with Air vessel presentation

AIR VESSEL:

Page 18: Reciprocating Pump with Air vessel presentation

The air vessel is a closed vessel as shown in fig.

The top half contains compressed air and lower half contains fluid being pumped.

Air and water are separated by a flexible diaphragm which is movable as per difference of pressure between two fluids.

Air vessel is connected very near to the pump at nearly pump level.

Without air vessel frictional head increases and reaches a maximum value at mid stroke and decreases to zero.

With air vessel frictional head is constant throughout the stroke.

Page 19: Reciprocating Pump with Air vessel presentation

The advantages of installing air vessels are: The flow fluctuation is reduced and a

uniform flow is obtained. The friction work is reduced. The acceleration head is reduced

considerably. Enables the use of higher speeds.

Page 20: Reciprocating Pump with Air vessel presentation

Flow into and out of Air vessel

Single acting pump: the flow into delivery side is only during a half revolution. This amount has to flow during full revolution.

the average velocity in the pipe = * Double acting pump: there are two

discharge per revolution.The average velocity in pipe = *

Page 21: Reciprocating Pump with Air vessel presentation

FRICTIONAL HEAD

Page 22: Reciprocating Pump with Air vessel presentation

EQUETIONS: Single acting pump:• The flow from cylinder, Q = A ωr sinθ• With air vessel average velocity = * • Flow through pipe = a . *

=• Flow into or out of the air vessel with =

0 – 360 = A ωr

Page 23: Reciprocating Pump with Air vessel presentation

Double acting pump:• Flow through pipe =

• At any point of time flow of cylinder = A ωr sinθ

• Flow into air vessel = A ωr

Page 24: Reciprocating Pump with Air vessel presentation

THANK YOU