DECLARATION
We are carried out project on “360 DEGREE FLEXIBLE DRILLING MACHINE ” here by declared that the matter included in this project is genuine work done by as and has not been submitted either to SBTET , A.P or any another university/Institute for fulfillment of the requirement of the degree.
Project Members: 15613-M-027 15613-M-016 15613-M-017 15613-M-022 15613-M-039 15613-M-003
K. VIJAY KUMAR J. VENKATA REDDY K. PAVAN K. NARESH N. CHETAN A. L N SWAMY
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Amrita Sai Institute of Science & Technology Approved by AICTE, Affiliated to SBTET, A.P Accredited by NAAC NAAC with with ‘A’ Grade Paritala, Kanchikacherla (MD), Krishna Dt. AP, India – 521 521 180 www.amritasai.edu.in
CERTIFICATE “360 DEGREE FLEXIBLE DRILLING This is to certify that the project entitled MACHINE” this report entitled is the bonafide record of wo rk done by
15613-M-027 15613-M-016 15613-M-017 15613-M-022 15613-M-039 15613-M-003
K. VIJAY KUMAR J. VENKATA REDDY K. PAVAN K. NARESH N. CHETAN A. L N SWAMY
In the Department of Diploma Mechanical Engineering by SBTET, A.P During the academic year 2015-2018.
Internal Guide
HOD
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External
ACKNOWLEDGMENT We would like to express our sincere thanks to our college “Amrita Sai Institute of Science & Technology ” for providing us with an opportunity to undergo to do project work.
I would like to thank to our guide Mr. K.SATHISH PRAKASH
M.tech
for his
encouragement and motivation about our project. It gives us immense pleasure to thank our HOD Dr. J. SAMPATH SURESH , Associate Professor, Department of Mechanical Engineering for being a source of constant inspiration,
precious guidance and generous assistance during the industrial Training. We deem it as a privilege to have worked under his able guidance. Without his close monitoring and valuable suggestions this work wouldn’t have taken this shape. We feel that his help is invaluable and unforgettable. We are also thankful to honorable principal Dr. M.SASI DHAR MCMS, FIE
B.TECH, M.E, PH.D, MISTE,
and we express our sincere gratitude and deep sense of respect for making us available
with all the required assistance and for his support and inspiration to carry our project in the Institute. We are also thankful to Chief Executive officer Dr. K. SAI MANOJ , B.Tech, M.Tech, Ph.d, Ceng, MCTSM, MIE, MCSI
and we express our sincere gratitude and deep sense of respect for making
us available with all the required assistance and for his support and inspiration to carry out project in the Institute. We are thankful to the teaching and non-teaching staff of Diploma Mechanical department for their direct as well as indirect help in our project. We are elated to avail ourselves to this opportunity to express our deep sense of gratitude to our parents.
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ABSTRACT Directional drilling machine which can be used based on drilling holes in various location and movement and easily operation done with high accuracy. Productivity can be improved by reducing total machining time and reduced human effort and reduced manufacturing cycle time. In this present age the application of micromachining operations continues to grow. These operations are required to fabricate the products required for sectors like medical science, automobile industries and electronics manufacturing etc. which deals with miniature trends. Drilling process is one of the machining processes which is used to drill micro holes not only in micro products but also in relatively larger work pieces which require ultra-small features which can be accomplished only by drilling process
K ey words: Drilling machine, Performance, Movement, Material, Operation etc.
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CONTENTS CHAPTER
1
TITLE
PAGE
STUDENT DECLARATION
1
CERTIFICATE
2
ACKNOWLEDGEMENT
3
ABSTRACT
4
CONTENTS
5
INTRODUCTION
6
1.1
7
General Aspects of Drilling Machine
2
DRILLING PROCESS
8
3
LITARATURE SURVEY
10
4
DEVELOPMENT OF DRILLING MACHINE
12
5
MOVEMENTS IN FLEXIBLE DRILLING MACHINE
13
5.1
14
Setup procedure
6
WORKING PROCEDURE
15
7
METHODOLOGY
15
8
COMPONENT & SPECIFICATION
20
9
FUTURE SCOPE
20
10
CONCLUSION & SUMMARY
21
5
INTRODUCTION Around 35,000 BCE, Homo sapiens discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earliest perforated artifacts such as bone, ivory, shells and antlers found, are from the Upper Paleolithic era.
Bow drill (strap-drills) are the first machine drills, as they convert a back-and forth motion to a rotary motion, and they can be traced back to around 10,000 years ago. It was discovered that tying a cord around a stick, and then attaching the ends of the string to the ends of a stick(a bow), allowed a user to drill quicker and more efficiently. Mainly used to create fire, bow-drills were also used in ancient woodwork, stonework and dentistry. Archeologist discovered a Neolithic grave yard in Mehrgrath, Pakistan dating from the time of the Harappans, around 7,500-9,000 years ago, containing 9 adult bodies with a total of 11 teeth that had been drilled. There are hieroglyphs depicting Egyptian carpenters and bead makers in a tomb at Thebes using bow-drills. The earliest evidence of these tools being used in Egypt dates back to around 2500 BCE. The usage of bow-drills was widely spread through Europe, Africa, Asia and North America, during ancient times and is still used today. Over the years many slight variations of bow and strap drills have developed for the various uses of either boring through materials or lighting fires. We had chosen the user defined project (UDP) for our final year project. We are decided our topic to develop the automatic multi-operational portable machine say like tapping, drilling, grinding, reaming, and other relative operation. This will make use of compressed air (pneumatic mechanism) for its operation. We will trying to develop the portable machine which will easily handle and cover a maximum working area from one station and make it more flexible to working easily. As a small industries the machine and operation method use for drilling, tapping and other similar process is not economically and eco friendly. As we know that drilling machine use the electricity as there power source these ma chine have many limitation like it is not flexible and not moveable, consume more floor area and main problem is that it need continuous electricity which increase the cost of production. The tapping operations are performed by use of convention tap or hand tap. during operation it is necessary with a hand tap to periodically
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reverse rotation to break the chip formed during the cutting process, thus preventing effect called crowding that may cause defect. In convention method, main problem causes during the tapping operation for big job industries and complex job these causes are created defect on tap tool, increasing operational lead time, inaccuracy of thread geometry, more production cost and more labour cost.
1.1
General Aspects of Drilling Machine:
Drilling is the operation of producing circular hole in the work-piece by using a rotating cutter called DRILL. The machine used for drilling is called drilling machine. The drilling operation can also be accomplished in lathe, in which the drill is held in tailstock and the work is held by the chuck. The most common drill used is the twist drill. It is the simplest and accurate machine used in production shop. The work piece is held stationary i.e. Clamped in position and the drill rotates to make a hole. Drilling machine is kind of machine rotating cutting tool which direction the drill feeds only on the machine axis(workmanship perforation). Drilling is operating while producing round holes in the piece work by using a rotating cutter called DRILL. A Drill is a tool fitted with a cutting tool attachment or driving tool attachment, usually a drill bit or driver bit, used for boring holes in various materials or fastening various materials together with the use of fasteners. The attachment is gripped by a chuck at one end of the drill and rotated while pressed against the target material. The tip, and sometimes edges, of the cutting tool does the work of cutting into the target material. This may be slicing off thin shavings grinding off small particles crushing and removing pieces of the work piece, countersinking, counter boring, or other operations. Drills are commonly used in woodworking, metalworking, construction and do-ityourself projects. Drills are available with a wide variety of performance characteristics, such as power and capacity. Drill machines have been the heart of every industry. Drilling holes in parts, sheets and structures is a regular industrial work. Perfect and well aligned drilling needs fixed and strong drills. Some parts cannot be drilled using fixed drills due to low space between drill bit and drill bed. We need to use hand drills in such cases but hand drills have alignment problems while drilling. So here we propose a 360 degree flexible drill that can be mounted on a table or wall and can be used to drill holes horizontally, vertically or even upside down. So this makes it possible for easy drilling in even complicated parts and surfaces. Thus we use rotating hinges 7
and connectors with motor mount and supporting structure to design and fabricate a mini 360 degree drill for easy drilling operations.
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DRILLING PROCESS Drilling is the method of making holes in a work piece with metal cutting tools. Drilling is associated with machining operations such as trepanning, counter boring, reaming and boring. A main rotating movement is common to all these processes combined with a linear feed. There is a clear distinction
between short hole and deep hole drilling. The drilling process can in some respects be compared with turning and milling but the demands on chip breaking and the evacuation of chips is critical in drilling. Machining is restricted by the hole dimensions, the greater the hole depth, the more demanding it is to control the process and to remove the chips. Short holes occur frequently on many components and high material removal rate is a growing priority along with quality and reliability.
Solid drilling is the most common drilling method, where the hole is drilled in
solid material to a predetermined diameter and in a single operation.
Trepanning is principally used for larger hole diameters since this method is
not so power- consuming as solid drilling. The trepanning never machines the whole diameter, only a ring at the periphery. Instead of all the material being removed in the form of chips, a core is left round the center of the hole.
Counter boring is the enlargement of an existing hole with a specifically
designed tool. This machines away a substantial amount of material at the periphery of the hole.
Reaming is the finishing of an existing hole. This method involves small
working allowances to achieve high surface finish and close tolerances.
The cutting speed, or surface speed (vc) in for drilling is determined by the periphery speed and can be calculated from the spindle speed (n) which is 8
expressed in number of revolutions per minute. During one revolution, the periphery of the drill will describe a circle with a circumference of π x Dc, where Dc is the tool diameter. The cutting speed also varies depending upon which cutting edge across the drill-face is being considered. A machining challenge for drilling tools is that from the periphery to the center of the drill, the cutting speed declines in value, to be zero at the center. Recommended cutting speeds are for the highest speed at the periphery. The feed per revolution (ƒn) in mm/rev expresses the axial movement of the tool during one revolution and is used to calculate the penetration rate and to express the feed capability of the drill. The penetration rate or feed speed (vf ) in mm/min is the feed of the tool in relation to the work piece expressed in length per unit time. This is known as the machine feed or table feed. The product of feed per revolution and spindle speed gives the rate at which the drill penetrates the work piece. The hole depth (L) is an important factor in drilling as is the radial cutting depth (a p) and feed per tooth (f z) for calculations.
Machining holes
Holes are either made or finish machined. Most work pieces have at least one hole and depending upon the function of the hole, it needs machining to various limitations.
The main factors that characterize A hole from the machining view point are: 9
- diameter - depth - quality - material - conditions - reliability - productivity
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LITERATURE REVIEW Micromachining operations play an important role in precision production industries. Out of the various machining processes, micro-drilling is used to produce micro holes in fuel injectors,
printed circuit board, aerospace materials etc. So in order to achieve the optimum working conditions various research were conducted by different researchers from across the globe. This report reviews some of the journal published b y them regarding optimization processes. Yogendra Tyagi,Vadansh Chaturvedi and Jyoti Vimal
have conducted an experiment on
drilling of mild steel, and applied the taguchi methods for determining the optimum parameters condition for the machining process using the taguchi methods and analysis of variance. The work piece used is mild steel (100mm×76mm×12mm) and the tool used is HSS with a point angle of 118° and diameter of 10 mm. Taguchi L9 orthogonal arrays is used here in order to plan the experiment. The input parameters are feed rate, depth of cut and spindle speed whereas the output responses are surface roughness and metal removal rate (MRR).In case of signal to noise ratio calculation, larger the better characteristics is used for calculation of S/N ratio for metal removal rate and nominal and small the better characteristics is used for the calculation of S/N ratio for surface roughness. After the analysis of the data obtained it is found that MRR is affected mostly by feed. Confirmation experiment was conducted using the data obtained from S/N ratio graphs and it confirmed with the results of taguchi methodology. In case of surface roughness analysis same procedure was followed where the significant parameter was found to be the spindle speed. Here too the confirmation experiment was conducted and this confirms the successful implementation of taguchi methods.
Timur Canel,A. Ugur Kaya,Bekir Celik studied the laser drilling on PVC material in order to increase the quality of the cavity. Taguchi optimization methods was used to obtain the optimum parameters. The material used in the experimental setup is PVC samples with 10
dimensions of 5mm×85mm×4.5mm. Surelite Continuum Laser is used to form the cavities. The input parameters are wavelength, fluence and frequency and the output response are aspect ratio, circularity and heat affected zone. Taguchi L9 orthogonal array is used to find the signal to noise ratio. Smaller the better characteristics is used for HAZ, larger the better characteristic is used for aspect ratioand nominal the better characteristic is used for circularity. Variance analysis is performed usingthe calculated S/N ratio to conclude optimum stage. It is found that most effective parameter for aspect ratio is frequency, second is wavelength and last is fluence. For circularity it is found that the most effective parameter is wavelength, fluence and frequency. For HAZ it is found that the most effective parameter is wavelength, second is frequency and last is fluence. The experimental results are compatible with Taguchi method with 93% rate.
Thiren G. Pokar,Prof. V. D. Patel used grey based taguchi method to determine the optimum micro drilling process parameters. hivapragash, K.Chandrasekaran, C.Parthasarathy, M.Samuel have tried to optimize the drilling process involving metal matrix composites(MMC) in order to minimize the damage done to it during the process by using taguchi and grey rational analysis. The work piece used is Al- TiBr 2(MMCs),with dimension of 100mm × 170mm × 15mm.The tool material is HSS with diameter of 0.6 mm. The input parameter are spindle speed, depth of cut and feed rate whereas the output parameter are MRR and surface roughness. For finding out the optimal combination of cutting parameters the results are converted into S/N ratios and higher the better type characteristics is used for MMR, and smaller the better characteristics is used for surface roughness.
Wen Jialing and Wen Pengfei used an orthogonal experimental design in order to find out the optimum process parameters for injection molding of aspheric plastic lens, to reduce volumetric shrinkage and volumetric shrinkage variation. Six input parameters were taken, each with 5 levels(Fill Time/sec, holding pressure/Mpa, holding pressure/times, cooling time/s, 6 melt temperature/°C, mold temperature/°C.L25(5 ) orthogonal array is used to plan the above
experiment. The parameters affecting both volumetric shrinkage and volumetric shrinkage variation are identified in order.
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4
DEVELOPMENT OF DRILLING MACHINE
A. Equipments used for the Experiment as shown:
Base plate
Vertical arm
Hrizontal arm
Suspension spring
Rollar bearing
Motor
Drill bit
Copper wire
Switch board
Guider
Fig. 1: Experimental Setup Diagram
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5
MOVEMENTS IN FLEXIBLE DRILLING MACHINE
This drilling machine possesses a radial arm which along with the drilling head can swing and move vertically up and down as can be seen in Fig. The radial, vertical and horizontal arm movement of the drilling head enables locating the drill spindle at any point within a very large space required by large and odd shaped jobs.
The tubular column on that the radial arm which moves up and down manually or it can powered movement then the drilling head here this is called drilling head which holds the drill spindle here in which the drill is mounted and is subjected to rotation. The entire head is mounted on the radial arm and this can move inward and outward from the drill axis. Also the horizontal arm can slide linearly on vertical arm. Not only that, as this along with this radial arm the drilling head moves upward and downward to have large gap between the to drill and job or there is a stoke length. Not only that further this radial arm can be rotated about the column rotated about the column, say about 360 degree.
The main movements in the machine are:
360 degrees rotation of arm joint.
Up & down movement of the horizontal arm on vertical arm.
Linear slide movement of horizontal arm.
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5.1
Setup Procedure
1) Base:
The base acts a support for the whole machine. It’s made of a mild steel. The base of the drilling machine supports the entire machine and when bolted to the floor, provides for vibration-free operation and best machining accuracy. The top of the base is similar to the worktable and may be equipped with t- slot for mounting work too larger for the table.
2) Arm:
There are two arms:
Vertical arm
Horizontal arm
The primary arm holds the secondary arm and it is with the help of this arm the 360° of rotation is transferred from the t plate to the secondar y arm in order to move the drill head at angles. They are made up of stainless steel.
3) Cross Slide:
We have used a hand drilling machine to be fixed on the cross slide. Our drilling machine can drill holes on concrete, wood and metal. The drill bit can be rotated both clockwise and anticlockwise direction
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6
WORKING PROCEDURE
Pneumatic multi-operation machine make use of compressed air obtained from compressor passes through pressure regulator & then passes through pneumatic gun. In pneumatic gun air exerts a axial spinning force on the spindle located inside the tool head which causes the drill tool to rotate inside the work piece with required RPM.
Fig. 2: Concept Design 7
METHODOLOGY
Step 1: Part collection
After some survey from market finally we bought pneumatic gun, pressure regulator, pipes, wheels for table & adaptor at the reasonable price.
Fig 3: Pneumatic Gun
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Fig 4: Pressure Regulato
Fig 5: Connecting pipe
Step 2: Define Joints
We defined joints which are used for relative motion of arms & also to rotate gun in 360 degree.
We designed mainly three types of joints such as ball joints, pin joints & rotational top head.
We can switch to an automation by using servo motor in the defined joints for future scope.
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Fig 6: Joints
Step 3: Design arms or linkages
We made arms or linkages having material of mild steel with help of fabricator.
We can use telescopic arms to extend the work envelope of pneumatic drilling machine for future scope.
Step 4: Fabrication of table
We made supporting table to sustain the load of pneumatic drilling machine by mounting it on the table.
We provide wheels to the table to provide the portability to the machine
Fig 7: Supporting table 17
Step 5: Assembling of component
After collection & designing of all parts we go for the final assemble to give the final touch to our machine.
Finally we assembled all the components in the one single unit and made universal drilling machine to justify our project title “DESIGN & DEVELOPMENT OF UNIVERSAL PNEUMATIC DRILLNG MACHINE”.
Fig 8: Partial Assembling
Fig 9: Final assembly
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Step 6: Fabrication of table
We did some experiment by drilling the material as wood, aluminium & cast iron using the appropriate tool & air pressure.
The experiments in the image shows the drilling of the workpiece. The other operation such as tapping, boring, grinding, thread cutting can also Performed by our machine.
Fig 10(a): Experiment 1
Fig 10(b): Experiment 2
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8
COMPONENT & SPECIFICATION
Fig 11: Component & specification (All dimensions are in mm)
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FUTURE SCOPE
We can use servo motor in our machine to provide the automation by giving auto feed.
We can use telescoping arm to increase the working envelope of the machine to reach in any direction easily.
We can use hydraulic system or hydraulic lubrication to operate the machine in smooth manner without including the less fatigue of man power .
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CONCLUSION & SUMMARY
Due to the various problems faced by conventional operation processes such as Poor thread finish, more time consumption, frequent tool breakage and many more. So, we have decided to design the machine which will make use of compressed air as a power source.
Above is the Future model of pneumatic machine on which the tapping ,drilling, boring etc operation is achieved by Pneumatic system and it eliminates all the problem faced by conventional operation process.
This pneumatic multi-operation Machine is to be presented for increasing their productivity as well as quality of job. It also gives the detailed description of machine mechanism and their different main parts of machine. In this we are defining different process parameters like spindle speed (rpm), cutting feed rate, cutting force, torque and power for their efficient working of operation.
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