Unit - 5

Drilling

Q1) What is drilling machine?

A1)

• Drilling is an operation in which a circular hole is made by removing some volume of metal from the job by cutting tool called drill.
• Drilling Machine is the simplest, moderate, and most accurate machine tool used in almost all the production shops and tool rooms. Drilling is basically a single purpose machine tool as its main purpose is to make holes in the work piece.
• A machine consists of a spindle that provides rotary motion to the drilling tool, which finally makes the hole in the job (work piece).
• A drilling machine is a type of machine in which the holes are being made on the work piece by making use of a rotating tool called drill bit or the twist drill. Drilling is basically a technology of creating holes.
• Drilling operation can also be performed on Lathe Machine. In the lathe machine, the work piece rotates and the drilling tool is held stationary in the tailstock.
• Boring: When we talk about drilling, boring is mostly discussed.
• Basically, Boring is a process in which the holes are enlarged that is already being drilled or cored. To perform boring action by a machine a special holder for the boring tool is required.

Q2) Describe construction of drilling machine.

A2)

• In a drilling machine, the drill is rotated and fed along its axis of rotation in the stationary work piece. Different parts of a drilling machine are illustrated in Fig. 1 and are discussed below:
• The head containing electric motor, V-belt which transmits rotary motion to the drill spindle at a number of speeds and V-pulleys.
• Spindle is made of alloy steel. Spindle rotates as well as moves up and down in a sleeve. A pinion engages a rack fixed onto the sleeve in order to provide vertical up and down motion of the spindle and hence the drill, so that the same can be fed into the work piece while drilling. Spindle speed or the drill speed can be changed with the help of V-belt and V-step-pulleys. Larger drilling machines are having gear boxes for the said purpose.
• Drill chuck is held at the end of the drill spindle which in turn holds the drill bit.
• An Adjustable work piece table is supported on the column of the drilling machine which can be moved both vertically and horizontally. These tables are having slots so that the vise or the work piece can be securely held on it.
• Base table is a made of heavy casting and it supports the drill press structure. The base supports the column which in turn, supports the table and the head.
• Column is a box section or vertical round which rests on the base and supports the head and the table. The round column have rack teeth cut on it so that the table can be raised or lowered depending upon the work piece requirements.
• It consists of following parts

1. Base

2. Pillar

3. Main drive

4. Drill spindle

5. Feed handle

6. Work table

Q3) What are the tolls used for drilling?

A3)

As mentioned, there are numerous styles of drilling gear. No rely which device you use, ensure to constantly put on protecting glasses, gloves, and a dirt mask. Of course, you need to constantly use good-first-rate gear.

So, let’s see what the maximum not unusual place styles of drills are.

Hand Drill

A hand drill is the most effective shape of drills. They are perfect for pre drilling holes earlier than placing the screws inside. Simply flip the drill left and proper till the top receives with inside the timber.

Then, maintain turning the drill to the proper till you attain the desired depth. These gear are awesome when you consider that they require no energy and are very clean to apply.

Hand Drill and Brace

Even eleven though we stay with inside the twenty first century, human beings nevertheless use those gear. They are a good deal quieter than electric powered drills and will let you make specific holes.

You can use them for timber and tender materials, however even in that case, it can’t make deep holes. There also are bits created specifically for this kind of drilling gear, which permit stepped forward precision.

Standard Electric Drill

These drills are awesome for maximum solving jobs. They will let you restoration heavier items through making holes and the usage of screws.

There are styles of electric powered drills: battery-powered drills, and those which might be powered through cable.

The first ones are exceptional due to the fact you don’t should be close to the energy deliver all of the time. Also, there aren't any any cables entering into your way. On the alternative hand, the drills powered through cable are typically a good deal extra powerful.

Hammer Drill

Hammer drills are just like general fashions however have an additional “hammering” feature. They are exquisite for drilling into difficult materials, which include concrete and stone. Many fashions will let you transfer among hammering and rotating, or maybe use each on the equal time.

Bench top Drill Press

These devices are a chunk hard to apply for novices however may be valuable to a expert DIYs. The fundamental gain of those drills is they will let you make very correct holes. Besides, they typically produce masses of energy and may be used for diverse materials.

Q4) Explain Drill Driver.

A4)

• A drill motive force is through some distance the maximum famous form of drill among homeowners – and the purpose in the back of this is pretty easy.
• Drill drivers are a truly flexible form of strength device that assist customers carry out a number of extraordinary duties.
• This consists of drilling holes and using screws into tough surfaces like wooden and metallic.
• A drill motive force is normally powered via a battery.
• Since those drills double up as a motive force, it manner that you could effortlessly tighten or loosen screws of various sizes and thickness the usage of this strength device directly.
• If you're seeking out an easy and complicated electric powered system on the way to are available on hand on numerous small-scale domestic projects, then a drill motive force might be all you want.
• For example, a drill motive force is a really perfect device in case you need to put in a shelf for your domestic. It can even show to be of notable gain while assembling store-bought, flat percent fixtures items, along with the ones offered at IKEA.
• It will assist you results easily drill via the fixtures if required, irrespective of whether or not it’s crafted from wood or iron.

Q5) What is hammer drill?

A5)

• It seems quite plenty similar to a drill motive force however an extra superior operation has.
• For this purpose, a hammer drill is likewise normally known as a hammer drill motive force.
• A true hammer drill will come up with the choice to pick among ordinary drilling, hammer drilling, or using automatically with the clutch.
• If you need to carry out screw-using duties, all you want to do is transfer to traditional drill settings.
• Therefore, in case you are seeking out a multipurpose strength device, going for a hammer drill is possibly your fine bet.
• Hammer drills are on occasion additionally known as percussion drills because of their ‘percussive’ mechanism.
• They supply brief however effective hammer thrusts in fast succession to interrupt via the cloth with extensively much less attempt than required otherwise.

Q6) What are general description for twist drill?

A6)

Twist drill bits are the maximum not unusual place form of drill bit and are used for regular drilling in all forms of fabric. They also are the maximum complicated because of the sheer wide variety of size, tip, and fabric specifications.

Length Designations:

The period of a twist drill has tons to do with its rigidity - a shorter bit can be more potent and much less probable to wander or smash however won't have the attain wanted for all jobs.

Twist drill bits to be used in automatic equipment have an real period specification (e.g. 4-1/2") at the same time as maximum (now no longer all) twist drills to be used in transportable drills are graduated period and use a call to specify the period range:

Jobber Length:

These are the maximum not unusual place twist drills and are a very good compromise among period and power. Jobber drills range in period in step with their diameter and commonly have a flute period of 9-14 instances the slicing diameter, i.e. a 1/2" jobber drill has a flute period of 4-1/2" (9 instances the diameter) with smaller drills having a bigger ratio.

Mechanics Length:

Shorter than jobber drills, mechanics period drills are named as such due to the fact they match into tighter areas and are much less probable to interrupt at the same time as nevertheless permitting an affordable flute period.

Screw Machine Length:

Also called "stubby period", those are the shortest not unusual place drill bits. Originally designed for screw machines, many humans decide upon those because of their excessive power and brought running clearance.

Extra Length:

These are more lengthy drill bits (as much as 18") with flutes extending the whole period of the bit. Extra period drills may be very fragile and without problems damaged so it is normally nice to drill as deep as viable with a jobber or shorter bit earlier than switching to a further period drill bit.

Aircraft Extension:

Similar in period to more period bits, plane extension drill bits emphasize attain over slicing intensity and feature a shorter flute period (approximately similar to a jobber drill). This makes the bit tons more potent and much less liable to bending and breaking.

Silver and Deming:

More than a period specification, Silver and Deming drill bits are 6" lengthy with a 3" flute period and a 1/2" diameter shank. All Silver and Deming bits are over 1/2" slicing diameter, starting from 33/64" to 1-1/2", and are in the main meant to be used in a drill press.

Q7) What is split drill point?

A7)

• This is a complicated drill factor that forestalls on foot and gives stepped forward penetration with much less effort.
• Available in 118 or one hundred thirty five diploma angles, break up factor drill bits are higher for drilling in curved surfaces or in alloy steels.
• They are extra highly-priced and extra tough to re-sharpen than widespread drill factors.
• V-Point Drill-Point:
• This is a unique excessive perspective tip used on drill bits for computerized wooden dull machines.
• V-factor drills are used to create thru-holes in sheet inventory for dowels or different meeting hardware.

Q8) What is bench drilling machine?

A8)

• Portable drilling tool can be carried and used anywhere with inside the workshop.
• It is used for drilling holes on work pieces in any position, which isn't viable in a favored drilling tool.
• The entire drilling mechanism is compact and small in duration and so can be carried anywhere.
• This type of tool is appreciably tailor-made for car built-up work.
• The motor is generally famous type
• These machines can accommodate drills from 12mm to 18 mm diameter.
• Portable drilling machines are operated at higher speeds.
• The hand vice is one secure manner of protecting cloth while drilling. It has jaws which are closed through turning a wing nut. In the instance the
• Perspex is held with inside the vice and it additionally rests on scrap timber at the desk.
• The peak of the desk is ready through adjusting the peak adjuster lever.
• When drilling the desk ought to be moved pretty near the drill bit in order that the space from the drill bit to the cloth is small.
• The protect ought to usually be used.
• This is the primary line of defense if the cloth being drilled breaks or shatters.
• Wearing goggles is the second one line of defense.

Q9) Explain right drilling machine.

A9)

• Every editorial product is independently selected, eleven though we can be compensated or obtain an associate fee in case you purchase something thru our links.
• Ratings and fees are correct and gadgets are in inventory as of time of publication.
• A proper attitude drill isn’t a device you’ll see in each kit, so you will be amazed to research simply how beneficial it could be.
• Right attitude drills are a… A proper attitude drill isn’t a device you’ll see in each kit, so you will be amazed to research simply how beneficial it could be.
• Right attitude drills are lesser-recognized DIY necessities that may be a game-changer for each person who frequently has to paintings in tight or limited spaces.
• Read on for greater information on what a proper attitude drill is and on which forms of tasks you’ll need to attain for one.
• The proper attitude drill is quite flexible and may be beneficial in almost any DIY undertaking that receives you into tight spaces, along with plumbing and different production tasks.
• For example, whilst drilling or screwing among ground joists, inner a cabinet, or everywhere the screws can be tough to attain with a regular drill.
• You can use a proper attitude drill in conditions like this to keep away from running with a screwdriver or different guide device.
• A proper attitude drill also can be a high-quality match when you have hassle drilling holes efficaciously or straight-on.

Q10) What is radial drilling machine?

A10)

Working of Radial Drilling Machine: Initially, whilst an energy deliver is given, the spindle rotates, that is pushed via way of means of the motor.

• Since the radial arm can circulate up and down with inside the column, the radial arm is adjusted in keeping with the operation and peak of the work piece.
• The spindle is hooked up to the chuck, and the drill bit is located with inside the jaw of the chuck.
• The head of the drilling system is likewise adjusted in order that the device is in the appropriate function to make a hollow with inside the work piece.
• After that, an appropriate feed is given, after which the drill bit without problems actions into the work piece. The power mechanism used with inside the drilling system is the rack and pinion mechanism. In rack and pinion mechanisms, gears are used to transform rotation to linear movement.
• When the hand wheel is rotated, the pinion this is connected to the rack additionally rotates, which converts the rotation to linear movement and consequently actions in the direction of the drill bit work piece. Radial drilling machines are used to drill mediums to huge and heavy work pieces.
• Those machines are used to drill holes in a given radial distance. It is specifically used whilst the component’s length is larges in peak.
• Radial drilling machines are on the whole designed for drilling holes in heavy jobs or work pieces.
• Since heavy paintings can't circulate plenty, the radial drilling system is made in the sort of manner that the system device can circulate any a part of heavy paintings without doing plenty paintings.

Q11) What is Universal drilling machine?

A11)

Universal Drilling Machine:

The drilling device is one of the maximum essential tools. It has converted a number of complicated production strategies into quite simple tasks.

• It is a crucial device this is utilized in numerous commercial and industrial operations; including construction, woodworking, metalworking etc. It is likewise normally referred to as a drill press.
• It is largely used for drilling holes of diverse sizes as in keeping with required depths on any floor area.
• Moreover it's far applied for tapping, reaming, counter boring, countersinking, spot going through etc. There are numerous classes of it including the upright, radial and unique cause drilling tools.
• Even eleven though these kind of are execute the essential drilling task; there are positive particular targets and further capabilities that may be achieved greater exactly and easily. A radial drilling device has a drilling head, that is set up to slip alongside a radial arm; and may be rotated, raised or lowered, on a vertical mast to regulate the placement of the drill above the paintings piece.

• It is used for several features that encompass drilling, reaming, boring, tapping, counter boring, lapping, screwing and see going through.
• These are able to drilling an extensive variety of substances crafted from solid iron, steel, plastic etc.
• The trendy variety consists of V belt pushed radial drill and all geared radial drill; in addition to the imported radial drill machines. These are generally categorized on the premise of the arm period and the width of the drill bit swing.
• The undeniable radial drilling usually has a vertical spindle that won't flow over the paintings piece. In the 1/2 of ordinary drilling the spindle may be swung in a single area over the paintings piece. A complete ordinary drilling device gives a wonderful quantity of flexibility. .
• It has the functionality to transport and swing in any aircraft and over any angle; without shifting the paintings piece. It is a distinctly flexible workshop device. The drilling spindle is hooked up to the cease of an arm.

Q12) Explain operations done by Drilling machine.

A12)

Though drilling is the primary operation performed in a drilling machine, a number of similar operations are also performed on holes using different tools. The different operations that can be performed in a drilling machine are:

1. Drilling
2. Reaming
3. Boring
4. Counter boring
5. Countersinking
6. Spot facing
7. Tapping

1. Drilling

Drilling is the operation of producing a cylindrical hole of required diameter and depth by removing metal by the rotating edge of a cutting tool called drill.

Drilling does not produce an accurate hole in a work piece. The internal surface of the hole generated by drilling becomes rough and the hole is always slightly oversize due to vibration of the spindle and the drill.

2. Reaming

• The size of hole made by drilling may not be accurate and the internal surface will not be smooth. Reaming is an accurate way of sizing and finishing a hole which has been previously drilled by using multi-point cutting tool known as reamer.
• The surface obtained by reaming will be smoother and the size accurate. The speed of the spindle is made half that of drilling.
• Reaming removes very small amount of metal (approx 0.375 mm). In order to finish a hole and bring it to the accurate size, the hole is drilled slightly undersize.

3. Boring

• Boring is the operation enlarging the diameter of the previously made hole. It is done for the following reasons.

a)     To enlarge a hole by means of an adjustable cutting tool. This is done when a suitable sized drill is not available or the hole diameter is so large that is cannot be ordinarily drilled.

b)    To finish a hole accurately and bring it to the required size.

c)     To machine the internal surface of the hole already produced in casting.

d)    To correct out of roundness of the hole.

e)     To correct the location of the hole as the boring tool follows independent path with respect to the hole.

4. Counter boring

• Counter-boring is the process of enlarging the existing hole to a larger diameter and making the surface at the bottom of the larger diameter flat.
• Counter boring is the operational enlarging the end of the hole cylindrically. The enlarged whole forms square shoulder with the original hole.
• This is necessary in some cases to accommodate the heads of bolts, studs and pins. The tool used for counter boring is known as counter bore.

• The counter bores are made with cutting edges which may be straight or spiral. The cutting speed for counter boring is at least 25% lesser than that of drilling.

5.  Countersinking

• Countersinking is the operation of making a cone shaped enlargement at the end of the hole. The included angle of the conical surface may be in the range of 60° to 90°.
• It is used to provide recess for a flat headed screw or a counter sunk rivet fitted into the hole. The tool used for counter sinking is known as a countersink.
• It has multiple cutting edges on its conical surface. The cutting speed for countersinking is 25% lesser than that of drilling.

6. Spot facing

• Spot facing is the process of enlarging the existing hole to a larger diameter and making the surface at the bottom of the larger diameter flat such that the depth of the enlarged hole is sufficient to provide a seat for the washer. Spot-facing is similar to the counter-boring except in spot-facing the depth of the enlarged hole is very small.
• Spot facing is the operational smoothing and squaring the surface around a hole.
• It is done to provide proper seating for a tutor the head of a screw or the washer. Counter bore or a special spot facing tool may be employed for this purpose.

7.  Tapping

• Tapping is the operation of cutting internal threads by means of a cutting tool called ‘tap’. Tapping in a drilling machine may be performed by hand or by power.
• When the tapes screwed into the hole, it removes metal and cuts internal threads which will fit into external threads of the same size.

Q13) Derive an equation for time estimation of drilling.

A13)

Time Estimation for drilling:

Machining Time:

• Ld (mm): Drilling depth
• i: Number of holes
• n (min-1): Spindle speed
• Fr (mm/rev): Feed per revolution (feed rate)

This formula is used to calculate the machining time from the drilling depth, the number of holes, the spindle feed, and the feed per revolution.

Example of drilling into SCM430 steel:

Drilling depth (ld) = 35 mm

Number of holes (i) = 1

Spindle speed (n) = 1500 min-1

Feed per revolution (fr) = 0.1 mm/rev

In this case, the machining time (Tc) is approximately 14 seconds (0.233 mm/min).

Q14) Explain Reaming.

A14)

A reamer is a form of rotary reducing device utilized in metalworking. Precision reamers are designed to make bigger the scale of a formerly fashioned hollow through a small quantity however with an excessive diploma of accuracy to depart easy sides.

There also are non-precision reamers which might be used for extra fundamental expansion of holes or for casting off burrs.

The procedure of enlarging the hollow is referred to as reaming. There are many exceptional forms of reamer and they will be designed to be used as a hand device or in a gadget device, along with a milling gadget or drill press.

A normal reamer includes a fixed of parallel immediately or helical reducing edges alongside the period of a cylindrical body.

Each reducing aspect is floor at a moderate attitude and with a moderate undercut beneath the reducing aspect

Reamers should integrate each hardness with inside the reducing edges, for lengthy lifestyles, and toughness, in order that the device does now no longer fail beneath the everyday forces of use.

They ought to most effective be used to dispose of small quantities of cloth.

This guarantees a protracted lifestyles for the reamer and an advanced end to the hollow. The spiral can be clockwise or counter-clockwise relying on usage.

For example, a tapered hand reamer with a clockwise spiral will generally tend to self-feed as its miles used, probably main to a wedging movement and consequent breakage.

A counter-clockwise spiral is consequently desired despite the fact that the reamer remains grew to become with inside the clockwise path.

For manufacturing gadget tools, the shank kind is generally one of the following: a preferred taper (along with Morse or Brown & Sharpe), an immediately spherical shank to be held through a collet, or an immediately spherical shank with a flat for a fixed screw, to be held through a strong

For hand tools, the shank quit is mostly a rectangular drive, supposed to be used with the identical form of wrench used to show a faucet for the reducing of screw threads. Reamers take off cloth on the circumference of the cylindrical bore hollow.

This occurs whilst they're grew to become with the assist of a faucet wrench with little strain from above in clockwise path with inside the bore hollow. In doing so, lubricating and cooling dealers roust be fed.

Straight and spiral-fluted reamers cannot deliver off any chips throughout the procedure, the chips stay with inside the chip grooves filling them after a quick time.

1 - Work piece,

2 - Cutting aspect,

3 - Chips With

Spiral-fluted reamers - in comparison to the drill - the hand of the helix is contrary to the path of rotation (sole exception: the structural reamer) on the way to save you the reamer from being drawn into the bore.

Such reamers are used, if there are wallet or grooves with inside the bore (feather or oil grooves).

Q15) What are the operations performed by reamer?

A15)

• Complexity confined too directly or tapered cylindrical blind or thru holes.
• Ideally, reaming allowances ought to be 0.1mm in keeping with 5mm of diameter, i.e. for a completed reamed hollow Ø20 mm, the pilot hollow to be about Ø19.6mm.
• However, drilled holes previous to reaming ought to be trendy length, anyplace possible.
• Allowances ought to be made for reamer-give up chamfers and the moderate taper on a few reamers whilst machining blind holes, despite the fact that extra applicable to thru holes.
• Standard sizes used anyplace possible.
• Through holes desired to blind holes.
• Sizes ranging Ø3–Ø100 mm No unique machines are used for reaming.
• Reaming may be executed on drilling machines, lathes, milling machines and machining centers, or via way of means of hand.
• Basic reamer sorts include: hand (directly and tapered), machine (rose and fluted), shell, expansion, adjustable and indelible insert reamers.
• Titanium nitride coatings are on occasion used to growth device life.
• Combination drills and reamers also are available.
• An inventory wrench of suitable length for containing the reamer is used.
• The reamer need to be stored in its accurate function relative to the job. It need to be run slowly and immoderate feed need to be avoided.
• It ought to be continually be grew to become with inside the slicing direction.
• Sufficient quantity of slicing fluid ought to additionally be employed.
• When casting off the reamer, it need to be grew to become with inside the slicing direction.
• Reamers with blunt or chipped edges need to now no longer be used.

Q16) What is boring?

A16)

• In machining, dull is the manner of enlarging a hollow that has already been drilled (or cast) with the aid of a single-factor reducing tool (or of a run of the mill head containing numerous such tools), along with in dull a gun barrel or an engine cylinder.
• Boring is used to reap more accuracy of the diameter of a hollow, and may be used to reduce a tapered hollow.
• Boring may be considered because the internal-diameter counterpart to turning, which cuts outside diameters.
• There are numerous sorts of dull. The dull bar can be supported on each ends (which handiest works if the present hollow is a thru hollow), or it could be supported at one end (which fits for each, thru holes and blind holes).
• Line boring (line dull, line-dull) implies the former. Back boring (again dull, again-dull) is the manner of achieving thru a current hollow after which dull on the "again" facet of the work piece (relative to the system headstock).
• Because of the restrictions on tooling layout imposed through the reality that the work piece on the whole surrounds the tool, dull is inherently particularly greater hard than turning, in phrases of reduced tool holding rigidity, multiplied clearance attitude requirements (restricting the quantity of help that may be given to the reducing edge), and trouble of inspection of the ensuing floor (size, form, floor roughness).

Q17) What are the boring machines in use?

A17)

• Line boring machines
• Tunnel boring machines
• Horizontal boring machines
• Directional boring machines
• Cylinder boring machines
• Jig boring machines
• Portable boring machines
• Vertical boring machines
• Coupling boring machines

Q18) Explain in detail horizontal drilling machine?

A18)

Which are almost not possible to maintain and rotate in an engine lathe or in a drill device. The dull device has, therefore, been growing commonly to do this.

So on this article, we can talk all of the statistics approximately the horizontal dull device.

In addition to its number one motive of dull, the variety of speeds and feeds presenting to the numerous traversing elements permit drilling, milling and going through to carry out with identical facility.

By the proper of easy attachments, using the device can make bigger nonetheless similarly to consist of screw cutting, turning, planetary grinding, or tools cutting. In kinds of dull device, the horizontal dull device is one of the maximum beneficial and crucial machines.

Let’s see the way it works. Following are the principle elements of horizontal dull device: Bed Headstock helping column End helping column Headstock Saddle and desk Boring bars

1. Bed

The mattress is that a part of the device that is becoming at the ground of the store and has a box-like casting. The mattress helps the column, tables and different elements of the device.

2. Headstock Supporting Column

The column gives aid to the headstock and publications it up and down appropriately with the aid of using the guide ways. The column which has whole homes and is closely ribbed to feature rigidity. Some columns are stationary, others can be made to slip alongside the mattress.

3. End Supporting Column

The quit helping column located at the alternative quit of the mattress homes. Bearing block is supplied for helping an extended dull bar. The column can be adjusted at the sideways of the mattress in the direction of or far from the spindle for helping the unique duration of dull bars. It can be moved at proper angles to the spindle as with inside the case of a ground kind device.

4. Headstock

The headstock mounting at the column helps, drives, and feeds the device. A spindle gives rotary motion to the device and the quill can be moved longitudinally to offer feeding motion of the dull cutter. The spindle nostril is supplied with a tapered hollow for receiving taper shanks of the dull bar or another device. A headstock can also additionally circulate up and down at the column for putting the device for unique heights of the paintings.

5. Saddle and Table

The tables aid the paintings and is, therefore, gives T-slots for containing numerous devices. The saddle lets in the paintings to be moved longitudinally at the mattress. The desk can be moved crosswise at the saddle. These moves can be sluggish or fast and are achieved with the aid of using hand or power.

6. Boring Bars

The dull bar helps the cutter for containing operations on jobs having massive bore diameters. For quick holes, the bar can also additionally aid at the headstock spindle quit only. For lengthy paintings, the bar is supported at the spindle quit and at the column bearing block.

Q19) Explain vertical boring machine.

A19)

Vertical Boring Machine:

In this uninteresting system paintings piece rotate on a horizontal desk and device stays desk bound besides for the feed

This unique layout of the system presents sure awesome benefits over a lathe for a selected magnificence of paintings.

The benefits are:

1. Large diameter and heavy work pieces, just like chucking jobs on a lathe, can be installation greater conveniently and quick than on a lathe. It is less difficult to put a work piece down at the desk in preference to to grasp it up.

2. The desk and the paintings it consists of rotate in a horizontal plane, and there may be no overhang as with inside the case of a lathe spindle, and therefore any hazard of bending the spindle which helps the heavy work piece is eliminated.

3. The desk being horizontal, the diameter of the desk can be designed as massive as feasible to help massive work pieces.

4. Multiple tooling can be tailored with inside the case a vertical uninteresting system with its turret kind device publish growing the charge of production.

Vertical turret lathe combines the benefits of the vertical uninteresting mill and the turret lathe.

• A vertical uninteresting system of smaller length is known as a vertical turret lathe.
• It has an index able turret installed upon the move rail above the desk for a couple of tooling.
• A 4 station rectangular turret aspect head which permits facing, turning, under reducing and plenty of different operations is installed on the aspect of the lathe.
• The move rail might also additionally have vertical changes and for ease of operation its far counter balanced.
• The turret installed at the saddle can be moved crosswise with the aid of using hand or power.
• The turret will also be moved in a vertical plane.
• The aspect head additionally has up and down and from side to side changes from the middle of the desk.
• The system is appropriate for uninteresting and turning railroad wheels, piston rings, equipment blanks, etc.
• Standard vertical uninteresting system is bigger in length than vertical turret lathe and there may be no turret lathe.
• The system is supplied with vertical heads and one or aspect heads.
• The system is especially supposed for uninteresting massive cylindrical and symmetrical work piece.
• Turbine castings, locomotive tires, etc. are a number of the not unusual place examples which want vertical uninteresting system.

Q20) What is jig machine?

A20)

Jig Machine:

• The jig uninteresting system is the maximum correct of all system equipment.
• This changed into evolved with inside the 12 months 1910 in Switzerland and used as a finding system.
• The actual jig borer changed into first constructed with inside the 12 months 1917 via way of means of Pratt and Whitney.
• The jig uninteresting machines at the moment are used for manufacturing of jigs, fixtures, equipment and different precision components which require excessive diploma of accuracy.
• They characterized via way of means of provisions of maximum accuracy via rigidity, low thermal enlargement and specific spacing holes.
• The machining accuracy could be very excessive, inside variety of 0.0025 mm.
• A jig uninteresting system resembles in look to a vertical milling system, however up to now its operation and accuracy are involved there cannot be any evaluation the 2.
• The spindle and different components of the system are extraordinarily inflexible to withstand deflection and the vibration is minimum.
• The spindle runs in preloaded antifriction bearing. The spindle housings are made from invar having a completely low coefficient of linear enlargement.
• The jig uninteresting system calls for to be operated in temperature may be maintained constant. This is crucial to save you inaccuracy with inside the system with inside the paintings being synthetic because of thermal enlargement of the metal.
• Vertical milling system kind resembles in production to a vertical milling system.
• The spindle rotates on a vertical column and the horizontal desk rests at the mattress in the front of the column.
• The positioning of the paintings established at the desk can be acquired via way of means of compound moves of the desk, perpendicular and parallel to the column face.
• Planer kind includes vertical columns at the 2 sided of the desk and is established at the base.
• The desk has reciprocating motion for adjustment of the paintings. The spindle is established at the move rail bridging the 2 vertical columns.
• In a planer kind jig borer, co - ordinate moves for hollow places are supplied via way of means of the longitudinal motion of the desk and the move motion of the spindle alongside the move rail.