FABRICATION OF SHELL FABRICATION OF SHELL AND TUBE HEAT AND TUBE HEAT

EXCHANGER TO COOL EXCHANGER TO COOL HYDRAULIC OILHYDRAULIC OIL

M.S. MOHAMED M.S. MOHAMED SHUJAHATHULLASHUJAHATHULLA

V.NARENDHRAKUMARV.NARENDHRAKUMAR R.PRAVEENKUMARR.PRAVEENKUMAR

Internal guide: Antony Aroul RajInternal guide: Antony Aroul Raj

A heat exchanger is defined as equipment which A heat exchanger is defined as equipment which transfers the heat from a hot fluid to a cold fluid.transfers the heat from a hot fluid to a cold fluid.

A A heat exchangerheat exchanger is a device built for efficient is a device built for efficient heat transfer from one medium to another, whether heat transfer from one medium to another, whether the media are separated by a solid wall so that they the media are separated by a solid wall so that they never mix, or the media are in direct contact. never mix, or the media are in direct contact.

They are widely used in space heating, They are widely used in space heating, refrigeration, air conditioning, power plants, refrigeration, air conditioning, power plants, chemical plants, petrochemical plants, petroleum chemical plants, petrochemical plants, petroleum refineries, and natural gas processing. One refineries, and natural gas processing. One common example of a heat exchanger is the common example of a heat exchanger is the radiator in a car, in which a hot engine-cooling radiator in a car, in which a hot engine-cooling fluid, like fluid, like antifreezeantifreeze, transfers heat to air flowing , transfers heat to air flowing through the radiator. through the radiator.

TYPES OF HEAT TYPES OF HEAT EXCHANGERSEXCHANGERS

Nature of heat exchange processNature of heat exchange process Relative direction of fluid motionRelative direction of fluid motion Design and constructional featuresDesign and constructional features Physical state of fluids Physical state of fluids

Nature of heat exchange Nature of heat exchange processprocess

Direct contact heat exchangers or Direct contact heat exchangers or Open heat exchangersOpen heat exchangers

Indirect contact heat exchangers.Indirect contact heat exchangers. RegeneratorsRegenerators Recuperators or Surface heat exchangersRecuperators or Surface heat exchangers

Relative direction of fluid Relative direction of fluid motionmotion

Parallel flow heat exchangerParallel flow heat exchanger Counter flow heat exchangerCounter flow heat exchanger Cross flow heat exchangerCross flow heat exchanger

Design and constructional Design and constructional featuresfeatures

Concentric tubesConcentric tubes Shell and tubeShell and tube Multiple shell and tube passesMultiple shell and tube passes Compact heat exchangerCompact heat exchanger

Physical state of fluidsPhysical state of fluids

CondensersCondensers EvaporatorsEvaporators

The main considerations taken into The main considerations taken into account in the design of heat account in the design of heat exchanger for a particular application exchanger for a particular application are thermal analysis, mechanical are thermal analysis, mechanical design, minimum pressure drop, design, minimum pressure drop, design for manufacture and cost.design for manufacture and cost.

COMPONENTSCOMPONENTS

TubeTube BaffleBaffle Tube SheetTube Sheet ShellShell End CoversEnd Covers O-RingO-Ring Compressed Asbestos Fibre (CAF) Compressed Asbestos Fibre (CAF)

GasketGasket

SHELL AND TUBE HEAT SHELL AND TUBE HEAT EXCHANGER TO COOL HYDRAULIC EXCHANGER TO COOL HYDRAULIC

OILOIL The aim of the project is to design and fabricate a The aim of the project is to design and fabricate a

heat exchanger of 5 lpm capacity to cool the heat exchanger of 5 lpm capacity to cool the hydraulic oil coming from power pack. hydraulic oil coming from power pack.

Hydraulic oil is used in power pack to actuate Hydraulic oil is used in power pack to actuate hydraulic cylinders to carryout various functions. hydraulic cylinders to carryout various functions. Once the oil is pumped from hydraulic pump to the Once the oil is pumped from hydraulic pump to the cylinder, after the actuation, the oil gets heated up cylinder, after the actuation, the oil gets heated up and returns to the oil sump. and returns to the oil sump.

Due to the accumulation of heat in the hydraulic oil, Due to the accumulation of heat in the hydraulic oil, the temperature of oil goes up and thus there is a the temperature of oil goes up and thus there is a decrease in the viscosity of hydraulic oil. Thus it is decrease in the viscosity of hydraulic oil. Thus it is necessary to cool the oil to bring down the necessary to cool the oil to bring down the temperature temperature

Specification:Specification:

Oil side inlet temperature Oil side inlet temperature = 48= 48cc Oil side outlet temperature Oil side outlet temperature = 40= 40cc Water side inlet temperature Water side inlet temperature = 32= 32c c Water side outlet temperature Water side outlet temperature = 38= 38cc Oil flow rate Oil flow rate = 5 lpm or = 5 lpm or

3m3/hr3m3/hr Velocity of oil flow Velocity of oil flow = =

8.65*10-3m/s8.65*10-3m/s Velocity of water flow Velocity of water flow = 0.6 m/s= 0.6 m/s Specific heat of cold water Specific heat of cold water = 4184 = 4184

J/Kg KJ/Kg K

MATERIAL SELECTIONMATERIAL SELECTION Tube materialTube material - Copper - high thermal - Copper - high thermal

conductivity . Therefore the heat is conducted conductivity . Therefore the heat is conducted more effectively.more effectively.

Fixed (Big):Fixed (Big): padded with SS304 of 3mm for cost padded with SS304 of 3mm for cost economy - SS padding to increase rust and economy - SS padding to increase rust and corrosion resistance.corrosion resistance.

Floating tube sheet (Small):Floating tube sheet (Small): made of SS304 made of SS304 material.material.

Baffle material: Baffle material: made of mild steel – no made of mild steel – no possibility of corrison since oil is in contact with possibility of corrison since oil is in contact with the baffles.the baffles.

Shell material:Shell material: I) made of mild steel of I) made of mild steel of IS1239 grade. IS1239 grade.

ii)The inlet and outlet socket ii)The inlet and outlet socket IS2062 IS2062 grade. grade.

iii)The flanges welded on the iii)The flanges welded on the two sides two sides of shell made of IS 2062 of shell made of IS 2062 grade mild grade mild steel. steel.

End Cover Material:End Cover Material: made of cast iron. made of cast iron. Sealing Material: i)Sealing Material: i)CAF gasket on fixed tube CAF gasket on fixed tube

sheet side sheet side ii)nitrile rubber ‘O’ring on the ii)nitrile rubber ‘O’ring on the

floating floating tube sheet tube sheet

FABRICATIONFABRICATION

TUBE SHEET TUBE SHEET FABRICATION :FABRICATION :

Machining of MS plate with SS304 padding is done in Machining of MS plate with SS304 padding is done in centre lathecentre lathe

fixed tube sheet is manufactured in the lathe machine of fixed tube sheet is manufactured in the lathe machine of 110mm outer diameter & 11mm thickness for fixed head.110mm outer diameter & 11mm thickness for fixed head.

Floating head 89mm outer diameter & 15mm thick is Floating head 89mm outer diameter & 15mm thick is also made. also made.

On the tube sheet face a undercut of 3mm is made to On the tube sheet face a undercut of 3mm is made to house a 4mm thick SS304 padding. house a 4mm thick SS304 padding.

The tube sheet with padding is kept on the hydraulic The tube sheet with padding is kept on the hydraulic press, then tag welded with a combination welding rod press, then tag welded with a combination welding rod of grade. of grade.

A centre hole of 3mm diameter is made on the padding A centre hole of 3mm diameter is made on the padding plate.plate.

Pad is welded with tube sheet .Pad is welded with tube sheet . The welded tube sheet with padding plate is machined to The welded tube sheet with padding plate is machined to

the required size in the lathe machine.the required size in the lathe machine.

Three baffles are cut and kept aside.Three baffles are cut and kept aside. On the drilling machine the centre hole of 6.35 mm On the drilling machine the centre hole of 6.35 mm

diameter is made on this tube sheet.diameter is made on this tube sheet. Then all the tube sheet and baffles are bolted in Then all the tube sheet and baffles are bolted in

bottom together. bottom together. one drill of 6.35mm diameter is drilled and locked to one drill of 6.35mm diameter is drilled and locked to

avoid of turning of platesavoid of turning of plates All the holes are drilled initially with the pilot drill of All the holes are drilled initially with the pilot drill of

size 6.35mm diameter and finally drilled to the size 6.35mm diameter and finally drilled to the required size of 9.54mm diameter.required size of 9.54mm diameter.

The baffle plate is cut 20% to have smooth turbulence The baffle plate is cut 20% to have smooth turbulence flow inside the shell tube holes are reamed with flow inside the shell tube holes are reamed with reamer of 9.5mm diameter on drill machine 20 %reamer of 9.5mm diameter on drill machine 20 %

MANUFACTURING OF MANUFACTURING OF SHELLSHELL

The pipe is cut and trimmed on the lathe The pipe is cut and trimmed on the lathe machine to required size.machine to required size.

Flange is machined on lathe and the PCD is Flange is machined on lathe and the PCD is marked on flanges.marked on flanges.

The holes on the flange are drilled on drilling The holes on the flange are drilled on drilling machine and finished flanges are welded on machine and finished flanges are welded on the face of the shell.the face of the shell.

Oil inlet and outlet port is drilled on shell.Oil inlet and outlet port is drilled on shell. Sockets with bsp threads are purchased and Sockets with bsp threads are purchased and

welded (3/4th inch thread) onto shell welded (3/4th inch thread) onto shell circumference.circumference.

SHELL

SHELL

END COVERS:END COVERS:

End covers are machined from cast End covers are machined from cast iron block to required on lathe.iron block to required on lathe.

The inlet and outlet, water The inlet and outlet, water connections on end covers as per the connections on end covers as per the drawing. drawing.

The PCD is also marked on end The PCD is also marked on end covers and drived to required size as covers and drived to required size as per drawing.per drawing.

End covers

END COVERS

COPPER PIPES: Copper pipe of required size are procured from market in the standard size available and cut to the required dimension.

COPPER TUBES – SIDE VIEW

COPPER TUBES – TOP VIEW

ASSEMBLYASSEMBLY

The cleaned tube bundle shell is kept on the The cleaned tube bundle shell is kept on the assembly table and the tube bundle is assembly table and the tube bundle is inserted inside the shell in between CAF inserted inside the shell in between CAF gasket and in between the inlet cover and gasket and in between the inlet cover and fixed tube sheet. fixed tube sheet.

Another gasket is provided and cover is Another gasket is provided and cover is fitted with shell with the help of bolts and fitted with shell with the help of bolts and nuts.nuts.

The required size of O ring is provided on the The required size of O ring is provided on the floating tube sheet and outlet cover is also floating tube sheet and outlet cover is also fitted fitted

TESTING OF TUBE BUNDLE:TESTING OF TUBE BUNDLE:

Water is filled on the shell side and the hydraulic Water is filled on the shell side and the hydraulic pressure pump is connected with one socket welded on pressure pump is connected with one socket welded on the shell and the other socket a valve is provided. the shell and the other socket a valve is provided.

Hydraulic pressure is created to a pressure of 1.5 Hydraulic pressure is created to a pressure of 1.5 times more than the working pressure of the heat times more than the working pressure of the heat exchanger i.e.15kg/cm exchanger i.e.15kg/cm 22 g for a operating pressure of g for a operating pressure of 10kg/cm2 g. 10kg/cm2 g.

The pressurized heat exchanger is kept for 1 hour and The pressurized heat exchanger is kept for 1 hour and checked for leaks.checked for leaks.

If there is any leak noticed the hydraulic pump is If there is any leak noticed the hydraulic pump is depressurized and further expansion carried out until depressurized and further expansion carried out until leak stops. leak stops.

end covers are also tested parallel for any leakage on end covers are also tested parallel for any leakage on the casting surface to a pressure of 7.5kg /cm2 the casting surface to a pressure of 7.5kg /cm2

CONCLUSIONCONCLUSION

The heat exchanger of capacity 5 litres The heat exchanger of capacity 5 litres per minute is designed and fabricated per minute is designed and fabricated

The heat exchanger is tested and found The heat exchanger is tested and found to be capable of maintaining the to be capable of maintaining the required inlet and outlet temperature of required inlet and outlet temperature of water and oil .water and oil .

The material selection of mild steel The material selection of mild steel which is combined with stainless steel at which is combined with stainless steel at the fixed plate is effective in cost the fixed plate is effective in cost reduction of the heat exchanger in an reduction of the heat exchanger in an economical manner. economical manner.

Temperatures maintained Temperatures maintained Oilside inlet : 48˚cOilside inlet : 48˚c Oil side outlet : 40˚cOil side outlet : 40˚c Water side outlet: 32˚cWater side outlet: 32˚c Water side outlet : 38˚cWater side outlet : 38˚c

Thank youThank you