Pumps

Pumps

Prepared By Rohit G. Sorte M.Tech

Pumps Amechanical device using suction or pressure to raise or move liquids, compress gases, or force air into inflatable objects.

Force (liquid, gas, etc.) to move in a specified direction by or as if by means of a pump

pumps fall into two main categories.

I. NONPOSITIVE DISPLACEMENT PUMPS II. POSITIVE DISPLACEMENT PUMPS

NONPOSITIVE DISPLACEMENT PUMPSA pump produces a force on the liquid that is constant for each particular speed of the pump. Resistance in a discharge line produces a force in the opposite directionWhen these forces are equal, a liquid is in a state of equilibrium and does not flow.If the outlet of a nonpositive-displacement pump is completely closed, the discharge pressure will rise to the maximum for a pump operating at a maximum speed.

NONPOSITIVE DISPLACEMENT PUMPS

POSITIVE DISPLACEMENT PUMPSThis pump, a definite volume of liquid is delivered for each cycle of pump operation, regardless of resistance, as long as the capacity of the power unit driving a pump is not exceeded.If an outlet is completely closed, either the unit driving a pump will stall or something will breakTherefore, a positive-displacement-type pump requires a pressure regulator or pressure-relief valve in the system.

POSITIVE DISPLACEMENT PUMPS

PARTS of a CENTRIFUGAL PUMP

A centrifugal pump is built up of TWO MAIN PARTS :THE ROTOR (or Rotating Element).THE CASING (or Housing or Body).

THE ROTORTheir two parts THE IMPELLERTHE SHAFT THE IMPELLER:-The rotating part of a compressor or other machine designed to move a fluid by rotation.THE SHAFT:- A long, narrow part or section forming the handle of a tool or club or the body of a spear or arrow

Impeller

Shaft

THE CASING (or Housing or Body).

This is the stationary part of the pump and includes the :Suction Nozzle.Discharge Nozzle.Seals.Bearings

Suction Nozzle.

The act or process of suckingThe force or condition produced by a pressure difference, as the force holding a suction cap onto a surfaceThe act or process of producing such a force or condition

Discharge NozzleDischargepressure describes the pressure of a liquid as it leaves a pump.

Higherdischarge pressures equal greater force behind the release while lower pressure means less. A pumps dischargepressure is influenced.

Seals

Pumps are devices that move fluid volume by mechanical or physical action. Pumps use a particular kind of seal in order to prevent leakage.

Bearings

Bearing is used For reducing friction & driver torque. For not getting leak also.

Centrifugal pumpsCentrifugal pumps, are a sub-class of dynamic axisymmetric work-absorbingturbomachineryCentrifugal pumps are used to transport liquids/fluids by the conversion of the rotational kinetic energy to the hydro dynamics energy of the liquid flow. The rotational energy typically comes from an engine or electric motor or turbine. In the typical simple case, the fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or(volute)chamber (casing), from where it exits.

Centrifugal pumps

Gear pumpA gear pumps which is used as a meshing gears, to pump the fluid by displacement. The Gear pumps are also widely used in chemical installations to pump fluid with a certain Gear pumps are positive displacement (orfixed displacement), meaning they pump a constant amount of fluid for each revolution.

Gear pumps

Liquid ring pumpAliquid ring/Nash pumpis a rotating positive displacement pump. They are typically used as avacuum pumpbut can also be used as agas compressor. The function of a liquid ring pump is similar to arotary vane pumpthe difference being that the vanes are an integral part of the rotor and churn a rotating ring of liquid to form the compression chamber seal. They are an inherently low friction design, with the rotor being the only moving part. Sliding friction is limited to the shaft seals. Liquid ring pumps are typically powered by an induction motor.

Liquid ring pump

Submersible pumpThe submersible pumps are multistage centrifugal pumps operating in a vertical position.Roduced liquids, after being subjected to great centrifugal forces caused by the high rotational speed of the impeller, lose their kinetic energy in the diffuser where a conversion of kinetic to pressure energy takes place.

Submersible pump

Screw pumpA pump that raises water by means of helical impellers in the pump casing.a hydraulic machine whose working member is a screw; used for pumping liquids, including high-viscosity fluids. Screw pumps, also referred to as worm pumps, are a type of rotary pump. The screw pump housing contains a driving screw and one or two driven screws. The points of engagement of the screws travel longitudinally along the shaft during rotation, thus forcing out the volume of liquid contained between the turns. It is potential energy that for the most part is transmitted to the liquids, as a result of which there is a considerable increase in pressure within it.

Screw pump

Multistage pumpA centrifugal pump containing two or more impellers is called a multistage centrifugal pump. The impellers may be mounted on the same shaft or on different shafts.For higher pressures at the outlet impellers can be connected in series.For higher flow output impellers can be connected in parallel.All energy transferred to the fluid are derived from the mechanical energy driving the impeller.

Multistage pump

Piston pumpA type of hydraulic pump that uses cam lobe action against pistons to generate hydraulic fluidA piston pump is a type ofpositive displacement pumps where the high-pressure seal reciprocates with the piston.Piston pumps can be used to moveliquidsor compressgases.

Piston pump

Hydraulic pumpThe mechanical device that is used to convert mechanical power into hydraulic energy is known as a hydraulic pump. The load that is responsible for the pressure is overcome with this device by creating sufficient power and generating a flow.The hydraulic pump has two functions to perform during operation, allowing atmospheric pressure to push liquid into the inlet line from the reservoir to the pump by the mechanical action created vacuum at the pump. The other function it performs is that the pumps mechanical action supplies the liquid to the pump outlet and then forced into the hydraulic system.

The following graphs address some of the problems that could occur when a pump is operating:

a. Overloading :- One risk of overloading is the danger of excess torque on a drive shaft.(You may need a larger pump)

b. Excess Speed :- Running a pump at too high a speed causes loss of lubrication, which can cause early failure.Excess speed also runs a risk of damage from cavitation. (use a higher displacement pump)

Pump Operation

Thank you ByRohit G. Sorte M.Tech