pneumatic surface grinding machine
DESCRIPTION
Pneumatic Surface Grinding Machine Project for Final year mechanical b-tech studentsTRANSCRIPT
Pneumatic Grinding Machine
Umesh Kumar Meher
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Pneumatic Grinding Machine
Pneumatic :
Grinding :
Pneumatics is a section of technology that deals with the study and application of pressurized air/gas to produce mechanical motion.
Grinding is a process carried out with a grinding wheel made up of abrasive grains for removing very fine quantities of material from the work piece surface.
Different Types of Grinding Machine
• Utility grinding machines
• Floor mounted utility grinding machine
• Bench type utility grinding machine
• Bench-type utility drill grinding machine
• Milling and grinding lathe attachment
• Surface grinding machine
Surface Grinding Machine
The surface grinding machine is used for grinding flat surfaces.
The work piece is supported on a rectangular table which moves back and forth and reciprocates beneath the grinding wheel.Reciprocating surface grinding machines generally have horizontal wheel spindles and mount straight or cylinder-type grinding abrasive wheels.
Pneumatic Grinding Machine
Important Parts
Power Input Source (Air Compressor)
Pneumatic Motor
Grinding Wheel
Work piece
Air Compresser
An air compressor is a device that converts power (usually from an electric motor, a diesel engine or a gasoline engine) into kinetic energy by compressing and pressurizing air, which, on command, can be released in quick bursts.Specification
Pneumatic Motor
A pneumatic motor or compressed air engine is a type of motor which does mechanical work by expanding compressed air.
The pneumatic motor used in our project is known as a rotary vane motor, uses air to produce rotational motion to a shaft. The rotating element is a slotted rotor which is mounted on a drive shaft. Air is pumped through the motor input which pushes on the vanes creating the rotational motion of the central shaft.
Rotation speeds can vary between 100 and 25,000 rpm depending on several factors which include the amount of air pressure at the motor inlet and the diameter of the housing.Model BVS 130
Weight 0.286/.587 kg
Dia of pneumatic turbine 70.6mmDia of rotor 67.6mm
Dia of spindle 7.93mmDia of inlet and outlet port 3.9mm
Specifications
Grinding Wheel
A grinding wheel is an expendable wheel that is composed of an abrasive compound used for various grinding (abrasive cutting) and abrasive machining operations.
Abrasive Type
Grit Size Grade Structure Bond
A 126 H 5 S
Al2O3 Fine Soft Close Pack Silicate
Grinding Wheel Specification
Grinding wheel Specification
Work pieceAbrasive material Percentage Work material Colour
Aluminium Oxide97-99% Al2O3 Hardened steel, HSS White
87-96% Al2O3Steel, cast iron Pink to brown
Silicon Carbide96-99% SiC HSS,
cemented carbides
Green
<96% SiC Aluminium , brass, brittle
materials
Black
Cubic Boron Nitrate (CBN) Tool steels, aerospace alloys
Synthetic Diamond Ceramics,
cemented carbides
Working Principle
Pneumatic Turbine
Rotation of Grinding Wheel
Grinding Operation
Air CompressorCompressed Air
The compressed air from the air compressor passed through the inlet port of the pneumatic turbine.
The high pressure and high velocity air then strike the vertical blades/slots.
This compressed air cause the blades to rotate in very high range, ranging from 1500 to 12000 rpm depending upon the supply of compressed air.
This rotor then cause the whole pneumatic circuit to rotate thus the spindle and shaft connected to it rotates.
Then the spindle rotation cause the rotation of the grinding wheel connected to it.
The compressed air once strike to the blades again comes out of the turbine by an exhaust port that present in the turbine.
AdvantagesThe grinding/grinding speed can be varied according to our needs by adjusting the timer.It is portableIt does not have any Prime mover, like electric motor related to the unit.As the air is freely available, we can utilize the air to cut the metal and hence it is economical.Simple in construction than mechanical hacksaw and grinderIt is a compact oneLess MaintenanceNo lubrication requiredNoiseless Can be rotate in both clockwise and anti-clockwise direction
Limitation
Only smaller size and soft metal can be cut
It is costlier than the conventional one
because of compressor unit.
Less efficiency when compressed to
mechanical device.
Leakage of air affects the working of the
unit.
High initial cost
References•Rao N P , Manufacturing Technology, volume-2, Metal Cutting And Machine Tools, 2nd Edition, Tata McGraw-Hill Publication, New Delhi, 2009•Mallik Kumar Asok Ghosh Amitabha, Manufacturing Science, 2nd Edition, EWP Publication, New Delhi, 2010•http://en.wikipedia.org/wiki/Pneumatic_motor•Pneumatic engines for power tools (http://www.directindustry.com/cat/motors-geared-motors-motion-control/pneumatic-motors-D-77.html)•Engineers Edge. Pneumatic actuator design and operation. Retrieved from http://www.engineersedge.com/hydraulic/pneumatic_actuator.htm•Braun, Adolphe: Luftlokomotive in "Photographische Ansichten der Gotthardbahn", Dornach im Elsass, ca.1875•http://en.wikipedia.org/wiki/Grinding_wheel•http://www.smithy.com/machining-handbook/chapter-8/page/3•http://www.vibco.com/docs/catalogs/silent-pneumatic-turbine-vibrators-catalog.pdf•http://www.durhamgeo.com/pdf/Rem-pdf/p32.pdf•http://www.iontrap.wabash.edu/publications/ajp_80_24_rohrbach_air_cannon.pdf
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