# reciprocating compressor and pumps

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• ThermodynamicsThermodynamics is the study of the effects of work, heat, and energy on a system.Thermodynamics is only concerned with macroscopic (large-scale)&microscopic changes and observations

• The Laws of Thermodynamics: SummaryZeroth LawIf two systems are each in thermal equilibrium with a third, they are also in thermal equilibrium with each other.

First Law The increase in internal energy of a closed system is equal to the difference of the heat supplied to the system and the work done by it: U = Q - W

Second Law Heat cannot spontaneously flow from a colder location to a hotter location.Third Law The entropy of all systems and of all states of a system is smallest at absolute zero*

• Thermodynamic Systems *

• Thermodynamic Processes Isobaric process : the pressure is constant.Isochoric process : the volume is constant.Isothermal process :the temperature is constant.

Adiabatic process : no heat enters or leaves the system; i.e. Q = 0.Isentropic process : the entropy is constant. It is also known as reversible adiabatic process.Isenthalpic Process: occurs at a constantEnthalpy

*

• The Ideal Gas LawIdeal gas law : PV = mRT or Pv = RT, where m is the no. of kmoles, v is the volume per kmole, T is the absolute temperature in K, and the gas constant R = 8.314 x 103 J/(K.kmol).For a constant quantity of gas, P1V1/T1 = P2V2/T2.Avogadro's law : For a given mass of anideal gas, the volume and amount (moles n) of the gas are directly proportional if thetemperature and pressureare constant. V is proportional to moles n v/n=k

PPVVT increasingTTV increasingP increasing

• The energy balance for a steady-flow device (nozzle, compressor, turbine and pump) with one inlet and one exit is:

• Fluid Moving Equipment

Fluids are moved through flow systems using compressors, pumps, fans and blowers. Such devices increase the mechanical energy of the fluid. The additional energy can be used to increaseVelocity (flow rate)PressureElevation

• CASCOMPONENT Intake Air Filters : Prevent dust and atmospheric impurities from entering compressor. Dust causes sticking valves, scored cylinders, excessive wear etc.Compressor : Pressurizes the air Inter-stage Coolers : Reduce the temperature of the air (gas) before it enters the next stage to reduce the work of compression and increase efficiency. They can be water-or air-cooled.After Coolers : Reduce the temperature of the discharge air, and thereby reduce the moisture carrying capacity of air.Air-dryers : Air dryers are used to remove moisture, as air for instrument and pneumatic equipment needs to be relatively free of any moisture. The moisture is removed by suing adsorbents or refrigerant dryers, or state of the art heatless dryers.Moisture Traps : Air traps are used for removal of moisture in the compressed air distribution lines. They resemble steam traps wherein the air is trapped and moisture is removed.Receivers : Depending on the system requirements, one or more air receivers are generally provided to reduce output pulsations and pressure variations.

• Parts of reciprocating Compressor

• COMPRESSORWhat is Compressor? A compressor is a device that pressurize a working fluid, one of the basic aim of compressor is to compress the fluid and deliver it to a pressure which is higher than its original pressure. PURPOSE To provide air for combustion To transport process fluid through pipeline To provide compressed air for diving pneumatic tools To circulate process fluid through certain process

• Types of compressor

• Compressor selection

• Capacity of compressorCapacity of Compressor basically indicated by following two parameterPressureFAD

• What is FAD- Capacity of a Compressor? The FAD is the volume of air drawn into a compressor from the atmosphere. After compression and cooling the air is returned to the original temperature but it is at high pressureSuppose atmospheric condition are Pa Ta and Va(the FAD) and the compressed condition are p , V and T

• Some definationsBore = Cylinder diameter.Stroke = Distance through which the piston moves.The two extreme positions of the piston are known as head-end and crank-end dead centers.Clearance Volume (Cl) : Volume occupied by the fluid when the piston isat head-end dead centre.Piston Displacement (PD) : Volume, a piston sweeps through.Compression Ratio (rv) : Ratio of cylinder volume with the piston at crank-end dead centre to the cylinder volume with the piston at head-end dead centre.Mechanical Efficiency : which gives an indication of the

losses occurring between the piston and driving shaft.

• Compressor Efficiency Definitions

Isothermal Efficiency

Isothermal power(kW) =P1 x Q1 x loger/36.7

P1=Absolute intake pressure kg/ cm2

Q1=Free air delivered m3/hr.

r=Pressure ratio P2/P1

_1124700618.unknown

• Compressor Efficiency Definitions

Volumetric Efficiency

Compressor Displacement

=( x D2 x L x S x ( x n

4

D

=Cylinder bore, metre

L

=Cylinder stroke, metre

S

=Compressor speed rpm

(

=1 for single acting and

2 for double acting cylinders

n

=No. of cylinders

_1124701132.unknown

• Reciprocating CompressorsTypes 1. Single acting The working fluid compressed at only one side of the piston2. Double acting The working fluid compressed alternately on both sides of the piston.

• Frame HN2T - 150NP

1Frame Assly.2Inner Head Assly. (LP)3Cylinder Assly. (LP)4Outer Head Assly. (LP)5Inner Head Assly. (HP)6Cylinder Assly. (HP)7Outer Head Assly. (HP)

• Frame, Cross Slide, Crank shaft and Connecting rod assembly1. Breather22. Crosshead23. Cross Head Nut35. Connecting Rod40.Big End Bearing36. Connecting rod Bolt28,29. Stud,Nut

• Breather: A vent or valve to release pressure or to allow air to move freely aroundsomething.

Crosshead: Is a mechanism used in large and reciprocating compressors to eliminate sideways pressure on the piston.Connecting Rod: connects thepiston to thecrank or crankshaft. Together with the crank, they form a simple mechanism that converts reciprocating motion into rotating motion.

• Crank Case42. Belt wheel13.Oil Seal Ring18. Gasket for Cover Flywheel end34. Crank Shaft25. Internal Circlip24. Cross Head Pin26.Cross Head Pin43. Oil Cooler8. Cover for Oil Pump end41. Oil Pump Assembly44.Oil filter12.Thrust washer

• Oil Seal Ring :It prevent the oil the oil to flow furtherGasket: is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while undercompression.Circlip: It is a type of fastenerorretaining ring consisting of a semiflexible metal ring with open ends which can be snapped into place, into amachinedgrooveon adowel pin or other part to permitrotationbut to prevent lateralmovement. There are two basic types: Internal and external, referring to whether they are fitted into a bore or over a shaft.

• Cross Head Pin : It connects thepistonto the connecting rod and provides a bearing for the connecting rod to pivot upon as the piston moves.

Thrust washer: Thrust washers are long-wearing flat bearings in the shape of a washer that transmit and resolve axial forces in rotating mechanisms to keep components aligned along a shaft. Crank Pin/Gudgeon Pin: Connects the pistonto the connecting rod and provides a bearing for the connecting rod to pivot upon as the piston moves

• Piston Parts1.Piston Assembly2.Rider Ring3.Piston Ring4.Sleeve for piston

• Piston Ring: Piston rings, mounted on the pistons of lubricated or non-lube (oil free) compressors, are designed to ensure that the gas is compressed and to provide a seal between the piston and the cylinder.Rider Ring:The function of rider rings, used mainly in oil free or mini-lube compressors, is to support or guide the piston and rod assembly and prevent contact between the piston and the cylinder (risk of seizure).

• Working:Reciprocating compressors generally, employ piston-cylinder arrangement where displacement of piston in cylinder causes rise in pressure.

• Sequence of operation

• Ideal indicator diagram

• The total work interaction per cycle :

• Chicago Pneumatic: For over a century Chicago Pneumatic has represented tough tools designed to make tough jobs easier.

Way back in 1889 John W. Duntley realized that construction workers in particular had a need for many tools that werent yet available. He founded Chicago Pneumatic Tool Company and set out on a lifelong mission to provide all types of industries and companies the tools necessary for their success.Over the years Duntley grew the company through product innovation, always insisting on product quality and reliability.Manufactures of air & gas compressors & pneumatic portable tools like grinders demolition tools, pumps vibrators, rammers hammers, etc.

Decades of innovation1901Chicago Pneumatic Tool Company is incorporated, after Duntley persuades youngsteel magnate Charles M. Schwabto invest in the company

• 1925CP seals an agreement to manufacture theBenz diesel engine, used in various racing cars in Europe at the time.1930sChicago Pneumatic construction and mining equipment is used in the building of the Lincoln Tunnel, New YorkTriborough Bridge, New YorkChicago subway systemBoulder Dam, ArizonaGrand Coulee Dam, WashingtonEight dams comprising the Tennessee Valley Authority flood control and power generation projectGolden Gate susp