Working principles of pumps History of Reciprocating pumps

Working principles of pumps

History of Reciprocating pumps In 17 th century Egyptians in Alexandria built reciprocating fire pump and it had all the parts of today’s pump. About 1805 Newcomen (Great Britain) built a reciprocating pump using steam engine as the driver. He was the first man to use seam for driving purposes. In 1840 -50 Worthington (U. S. A) developed a steam engine driven pump. Then many developments came.

History of Centrifugal pumps The inventor ca not be name with assurance. In the 17 th century Jordan, an Italian had made some drawing of a centrifugal pumps. In the early 18 century French physicist Papin built a centrifugal pump of primitive design. In 1732 Demouir pumps was put on service in France, In 1818 Andrews ( USA) built a single stage centrifugal pump. Then many developments came in the industry. . .

History of best pump Human heart. Everybody knows Who invented.

200 meters 100 Bar M 10 kms Pumps are used to move liquids • from a lower pressure system to higher pressure • From a lower elevation to higher elevation • From one place to another place at different/same elevation and pressure.

200 meters 100 Bar M Pumps add pressure energy to over come elevation needs ( potential energy) Frictional losses Delta pressure requirements Energy needed for pumps= volumetric flow*pressure 10 kms

Power required for pumping Power = mass X dynamic head Power ( k. W)= H Q r/367000 H = Total head in meters Q=Flow M 3/H r=Density in Kg/M 3 Power ( k. W)= H Q r/35. 99 H = Total head in bar. A Q= Flow M 3/H r=Density in Kg/M 3 Pleased divide by efficiency for actual power Please refer Perry

How to give energy ? Centrifugal force (throwing) Positive displacement (physically pushing)

Centrifugal pumps

Working principles centrifugal pumps

1. Impeller 2. Casing 3. Eye 4. Seal/packing 5. Wear ring Parts of a centrifugal pump

Advantages of centrifugal pumps 1. It simple and easy to construct. Available in different materials. 2. Absence of valves. Less maintenance. 3. High rpm design. Can be coupled to a motor directly. 4. Steady delivery. 5. No damage in delivery is blocked. 6. Smaller in Size when compared to reciprocating type for the same capacity. 7. Can handle slurries.

Dis-Advantages of centrifugal pumps 1. For high pressure we need multistage pump which are complex to construct. 2. Efficiency is high only over a range. ( explain graph) 3. Usually not self priming 4. Non return valve is needed in the delivery to avoid back flow. 5. Very viscous fluid can not be handled/

Types centrifugal pumps Typical classification • Single stage • Multistage Explain why and how

Single stage

Multi stage Multistage pumps are used to limit rpm and whenever we have high DP. Example BFW pumps.

Thrust balance centrifugal pumps 1. Double suction pumps 2. Thrust balance in multistage pumps Stage arrangement 3. Thrust balance line and thrust disk and bearing

Double suction pumps Sea water

Double suction pumps 323 -J UREA

Multistage pumps Thrust balance in a multi-stage pump

Multistage BFW Pump Ammonia

Multistage pumps In Out Thrust balance in a multi-stage pump Explain the principle of balance disc Thrust balance line and caution

Multistage pump Explain thrust balance

Positive displacement pumps

Positive displacement pumps • Reciprocating • Rotary

Reciprocating Pumps • Piston type Vertical& Horizontal & double acting • Plunger type • Diaphragm pump

Reciprocating pumps Explain double acting, plunger type , vertical, horizontal, multistage

Diaphragm pumps

Diaphragm pumps

Diaphragm Reciprocating pumps Basic principle is similar to a reciprocating plunger pump/ Plunger pressurizes the hydraulic oil which when pressurized pushes the diaphragm and discharge starts. Stroke length can be adjusted and hence the dosing flow rate. No direct contact of plunger with the solution.

Diaphragm Reciprocating pumps Figure 1: The air valve directs pressurized air to the back side of diaphragm "A". The compressed air is applied directly to the liquid column separated by elastomeric diaphragms. The compressed air moves the diaphragm away from the center block of the pump. The opposite diaphragm is pulled in by the shaft connected to the pressurized diaphragm. Diaphragm "B" is now on its air exhaust stroke; air behind the diaphragm has been forced out to atmosphere through the exhaust port of the pump. The movement of diaphragm "B" toward the center block of the pump creates a vacuum within the chamber "B". Atmospheric pressure forces fluid into the inlet manifold forcing the inlet ball off its seat. Liquid is free to move past the inlet valve ball and fill the liquid chamber.

Diaphragm Reciprocating pumps Figure 2: When the pressurized diaphragm, diaphragm"A", reaches the limit of its discharge stroke, the air valve redirects pressurized air to the back side of diaphragm "B". The pressurized air forces diaphragm "B" away from the center block while pulling diaphragm "A" to the center block. Diaphragm "B" forces the inlet valve ball onto its seat due to the hydraulic forces developed. These same hydraulic forces lift the discharge valve ball, forcing fluid flow to flow through the pump discharge. The movement of diaphragm "A" to the center block of the pump creates a vacuum within liquid chamber "A". Atmospheric pressure forces fluid into the inlet manifold of the pump. The inlet valve ball is forced off its seat allowing the fluid being transferred to fill the liquid chamber.

Diaphragm Reciprocating pumps Figure 3: Upon completion of the stroke, the air valve again redirects air to the back side of diaphragm "A", and starts diaphragm "B" on its air exhaust stroke. As the pump reaches its original starting point, each diaphragm has gone through one air exhaust or one fluid discharge stroke. This constitutes one complete pumping cycle. The pump may take several cycles to become completely primed depending on the conditions of the application.

Gear and screw pumps • High pressure and viscous fluids • Used in Samd for lube and seal oil pumps air booster of ammonia, 102 -J

Gear pumps • High pressure and viscous fluids Example : lube/ seal oil pumps

See the solution is pushed out of the pump physically

Only one gear is used ( Explain)

Screw pumps • High pressure and viscous fluids Example : lube/ seal oil pumps

SCREW PUMP Talk about selection, parallel operation, reverse running etc.

SCREW PUMP

SCREW PUMP Talk about selection, parallel operation, reverse running etc.

SCREW PUMP Talk about selection, parallel operation, reverse running etc.

Sealing in pumps

Sealing in pumps Fixed sealing – Packing Centrifugal and reciprocating Rotating – Mechanical seal Centrifugal, gear pumps etc

Gland Packing

Impeller Gland packing principles Stuffing box Explain packing stuffing box , heat generation and cooling techniques. , Lantern rings , flushing , Cost and choice etc.

Packing Explain packing stuffing box , heat generation and cooling techniques. , Lantern rings , flushing , Cost and choice etc.

Packing

Mechanical seal

Stuffing box Impeller 3 2 1 Rotating Fixed Three sealing points of a mechanical seal ( 1, 2, and 3)

Mechanical seals

Mechanical seals

Mechanical seals Explain working , heat generation and cooling techniques, flushing , Cost and choice etc.

Mechanical seals Seal types

Mechanical seals

Mechanical seals

Double seals – Hazardous liquids Explain need, sealant glycol, flushing etc.

Special Magnetic seals for hazardous/ expensive / corrosive fluids

Submersible pumps Self-priming as they are inside the liquid. Lube oil consoles , sump tanks, hazardous solution pumping etc.

End of part 1