Study on Effect of Some Parameters on Drilling

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International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 tudy on Effect of ome Parameters on rilling K Usha ani Academic Consultant eptof Mechanical Engineering

1 International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 tudy on Effect of ome Parameters on rilling K Usha ani Academic Consultant eptof Mechanical Engineering chool of Engg & Tech ri Padmavathi Mahila University,TIrupathi Chittor ist,andhra Pradesh India ABTACT This project work entitled tudy on effect of some parameters on drilling is carried out in the machine tool laboratory, epartment of Mechanical Engineering rilling process is one of the important process in Engineering Industries particularly in metal cutting area, hence great emphasis should be given to this process Guide: Areenivasulueddy AsstProfessor ept of Mechanical Engineering VU College of engg, Tirupati,Chittor(ist,Andhra Pradesh India drill may produce one as much as 05 mm oversize The rotary motion is called cutting or main motion The drill is moved in a straight line towards the fixed work piece This movement is called feed and it controls the thickness of the chips In the present work, effects of parameters such as speed, feed, point angle of drill tool, during drilling of mild steel with H drill bit are studied From this, the parameters such as thrust force, torque, power, temperature and chip thickness are calculated Finally, the combined effects of machining parameters are studied and their optimal levels are recommended ITUCTI rilling is the operation of producing a cylindrical hole by removing metal by the rotating edge of a cutting tool called the drill The drilling is one of the simplest methods of producing a hole Before drilling the centre of the hole is located on the work piece by drawing two lines at right angles to each other and then a centre punch is used to produce an indentation at the centre The drill point is pressed at this centre point to produce the required hole rilling does not produce an accurate hole in a work piece and the hole so generated by drilling becomes rough and the hole is always slightly oversize than the drill used due to the vibration of the spindle and the drill A 12 mm drill may produce a hole as much as 0125 mm oversize and a 22 mm rilling action on drill machine (a Cutting motion (b feed motion Base: The base of a radial drilling machine is a large rectangular casting that is finished on its top to support a column on its one end and to hold the work table at the other end In some machines T- slots are provided on the base for clamping work when it serves as a table Column: The column is a cylindrical casting that is mounted vertically at one end of the base I: Page 7

International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 It supports the radial arm which may slide up or down on its face adial arm: The radial arm that is mounted

2 International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 It supports the radial arm which may slide up or down on its face adial arm: The radial arm that is mounted on the column extends horizontally over the base It is a massive casting with its front vertical face accurately machined to provide guide ways on which the drill he may be made to slide The arm may be swung round the column In son machines this movement is controlled by a separate motor rill head: The drill head is mounted on the radial arm and drives tile drill spindle It encloses all the mechanism for driving the drill at multiple^ speed and at different feed All the mechanisms and controls are house within a small drill head which may be made to slide on the guide ways of the arm for adjusting the position of drill spindle with respect to the work pindle drive and feed mechanism: There are two common methods of driving the spindle A constant speed motor is mounted at the extreme end of the radial arm which balances partially the weight of the overhanging arm The motor drives a horizontal spindle which runs along the length of the arm and the motion is transmitted to the drill head through bevel gears By train of gearing within the drill head, the speed of the spindle may be varied Through another train of gearing within the drill head, different feeds of the spindle are obtained EXPIMETA ETUP Watt Meter ( watts Thrust Force and Torque -m meter Temperature Gun (centigrade Micrometer peed variable/s Feed ev Experiment procedure: A new tool (H of Addison Company was used for experimental work, it had point angle of Table Properties of H: 1 ensity kg/m 3 2 Poisson s 027 atio 3 Young s MPA Modulus 4 Coefficient of thermal expansion 117*10-05 /C 5 pecific heat *10 08 capacity mm 2 /sec 2 Thermal /sec C conductivity The process is performed by keeping any one of speed or feed kept constant and other parameter varied The process carried out under various point angles such as 100 o, 110 o, 118 o, 100 o The following observations were made TABE 1: F IFFET TIG PE Point angle=100,drill bit size=18mm,cutting feed=03mev were kept constant and then I: Page 8

3 International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 TIG PEE (rpm U T f kgm PW P AT ( 0 c KE m TABE 2: F IFFET FE Point angle=100,drill bit size=18mm,cutting peed=300rpm were kept constant and then FEE ev T kgm P WE (watt s P AT ( 0 c KE m TABE 3: F IFFET TIG PE Point angle=110,drill bit size=18mm,cutting feed=03mev were kept constant and then TI G PE (rpm T kgm PW P ( 0 c KE m TABE 4: F IFFET FE Point angle=110,drill bit size=18mm,cutting peed=300rpm were kept constant and then FE ev T kgm PW P AT ( 0 c KE m TABE 5: F IFFET TIG PE Point angle=130,drill bit size=18mm,cutting feed=03mev were kept constant and then CU TTI G PE (rp m T kgm PW P ( 0 c KE m TABE : F IFFET FE Point angle=130,drill bit size=18mm,cutting peed=300rpm were kept constant and then I: Page 9

4 International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 FE ev T kgm PW P ( 0 c KE m TABE 7: F IFFET TIG PE Point angle=118 0,drill bit size=18mm,cutting feed=03mev were kept constant and then FEE m/ rev T f kgm PW (watt s P ( 0 c KE m TI G PE (rpm T f kgm PWE P AT ( 0 c KE m TABE 8: F IFFET FE Point angle=118,drill bit size=18mm,cutting peed=300rpm were kept constant and then Thrust force, Torque, Power vs feed UT The output parameters of Thrust force, Torque and Power varied linearly with both the parameters feed and speed Thrust force, Torque and Power increases if speed or feed increases Thrust force, Torque and Power decreases if speed or feed decreases 1The graph between Thrust force, Torque, Power and feed keeping speed= 300 rpm and Point angle=118 o 2The graph between Thrust force, Torque, Power and speed keeping feed= 03mm and Point angle=118 o Thrust force, Torque, Power vs speed I: Page 10

5 International Journal of Engineering Trends and Technology (IJETT Volume 15 umber 1 ep 2014 CCUI From the results, it is observed that thrust force, torque and power linearly varies with the speed and feed The optimum point angle for High peed teel (H is 118 o as it is the angle at which Power consumed, temperature of the chip are minimum 3The graph between Power consumed and Point angle is drawn with keeping constants at speed=300rpm and feed=03mm Power consumed and Point angle Further, the best optimum point angle is for H drill bits, which consumes minimum power It is also found that temperature is minimum at point angle FECE: 1AM(1999AMhand book,vol1:machiningam,ua,pp Kim J,ornfeldd A (2002evelopment of an analytical model for drilling burr formation on ductile materialstrans AME 124: Ko,Chang JE, YangGE(2003Burr minimising scheme in sdrillingj Mater Process Technical 140: Gillespie K( 1994 Process control for burrs and deburring3international conference on precision surface finishing and burr 5Montgomery C( 1991 esign and analysis of experiments,3 rd ednarizona state university,newyork 4The graph between temperature at cutting and point angle is drawn with keeping constants at speed=300rpm and feed=03mm PetropoulosG, TZIATZIA I,anghel C( 2005 Temperature at cutting and point angle I: Page 11

ROOP LAL Unit-6 Drilling & Boring Mechanical Engineering Department

ROOP LAL Unit-6 Drilling & Boring Mechanical Engineering Department Lecture 4 Notes : Drilling Basic Mechanical Engineering ( Part B ) 1 Introduction: The process of drilling means making a hole in a solid metal piece by using a rotating tool called drill. In the olden