MT ( Light ) Shop , Lathe Section , Milling Section, Grinding Section, Jig section ,

We find the five Sections in light machine shop. There are-

1. Shaper Section

2. Lathe Section

3. Milling Section

4. Grinding Section

5. Jig Section

Shaper Section:

There are two types of shaper machine-

1.Vertical shaper machine or slotting machine

2. Horizontal or hydraulic shaper machine

Figure: Shapper machine

1) Vertical shaper machine or slotting machine : Vertical shaper machine situated vertically. Here job move clockwise. Mainly it is used for finishing. The table is fixed. It is also used for internal gear cutting. It is produce key way , warm gear.

# Origin : RUSSIA

# Length : 25-200 mm

# Stroke : 40-163

2) Horizontal or hydraulic shaper machine : Here job is fixed and ram moving to and fro motion. It is used for metal cutting.

Lathe Section

Lathe is one of the most important machines in any workshop. The initial objective of using a lathe was to remove material.

Principal parts of a lathe machine :

(1) (1) Bed

(2)(2) Headstock

(3) (3)Tailstock

(4) (4) Carriage

(5) Feed mechanism

(6) Thread-cutting mechanism

(7) Tool post

(8) Live centre

(9) Dead centre

(10) Spindle

In BITAC there are 23 pieces lathe machine in the light machine shop. There has some types-

1. Capstan lathe machine

2. Center lathe machine

3. Copping lathe machine

1) Capstan lathe also called production lathe because it hold 6 job at a time and cutting comperativly. Less time is required in making a desired shape of job. Maximum 8 tools used in this lathe. It has no extra lead screw but it can cutting thread.

2) Center lathe machine : The center lathe machine used to turn and cut metal. A few of the common operations are facing, straight turning, taper turning, thread cutting, parting, necking, knurling and forming.There are two type center lathe machine – BECO

CL 250, BECO CL 160.

3) Copping lathe machine : It is very important type lathe machine because it can copy the design. Here the lead and pitch is same. It’s step 0.25, 0.5, 0.75,1 inch. It can carry about 1 ton weight.

Milling Section

A milling machine is one that is designed to remove metal and other materials from a piece of work with a revolving cutter as the work is fed against it.

Principal parts of a milling machine :

(1) Column, (2) Knee, (3) Table, (4) Spindle, (5) Over-arm

In BITAC there are three types of milling machine. Such as-

1.Vertical milling machine

2. Horizontal milling machine

3. Gear hob machine

Vertical milling machine :

In vertical milling machine the spindle and table are similarly located. The spindle has the vertical movement and the table has vertical, longitudinal and transverse movement.

Operations : Boring, Facing, Drilling, Key cutting, Angular cutting.

Horizontal milling machine :

In horizontal milling machine is one which the longitudinal travel of the table is fixed at right angels to the spindle.

Gear hob machine :

Gear hob machine cut only gear. Such as Spur gear, Helical gear and Warm gear. In this machine when spindle move 12 times then the table move only one time.

Grinding Section

A grinding machine is a machine which employs a grinding wheel for producing cylindrical, conical, or plane surface accurately and economically, and to the proper shape, size and finish.

Types of Grinding Machine :

1. Cutter grinding machine

2. Cylindrical grinding machine ( External )

3. Surface grinding machine

4.Internal grinding machine

5.Center grinding machine

1) Cutter Grinding Machine : A cutter grinding machine is a machine that holds the cutter while a rotating abrasive wheel is applied to the edges for the purpose of sharpening it. Main parts of this machine are work head, work head spindle, longitudinal slide, wheel head, wheel head spindle and vertical slide.

2) Cylindrical Grinding Machine (External) :

External grinding, as commonly thought of, is the act of grinding the outside diameter of a piece of work while it is revolving on its axis for the purpose of reducing it to size, and leaving a fine finish. However, external grinders are also used to produce external cams, eccentrics and special forms on the outside diameter of work.

Capacity: Bed size – 42 inches, Max. diameter – 10 inches, Max. length – 6 ft.

Operation: Grinding the outside diameter of a piece of work, producing external cams, eccentrics, and special forms on the outside diameter of work.

3) Surface Grinding Machine: Surface grinding is the act of producing and finishing flat surfaces by means of a grinding machine employing a revolving abrasive head.

Limitation: Only flat jobs can be machined, the cylindrical shaped job can not be machined by this grinding machine.

4) Internal Grinding Machine: Internal grinding is the operation of grinding straight-cylindrical, tapered or formed holes to accurate size.

Capacity: Max. length – 2.5 ft., max. diameter -5 inches

5) Center Grinding Machine :

In center grinding machine headstock and tailstock are not included.

Capacity: Max. diameter - 8 inches.

Advantages: It can be used for large production.

Limitation: The job must not involve more than step.

Jig section

In BITAC jig section two type of jig machine is situated.

1.Jig boring machine

2. Jig grinding machine

1)Jig boring machine : Jig boring machine is used for boring. Hard metal can not be cut by this machine. In this machine it is possible to boring center to center 100% accurately. It is also produce 100% accurate diameter. It has possible to drill only 0.3 mm. Spindle is moving. It can boring 0.125-6.5 inch diameter.

5 degree F( 3 degree C) = 0.0001 inch( 0.0025 mm)

# Speed : 2500 rpm

2) Jig grinding machine : It can be operated for hard and soft metals. It is used for most accurate grinding. The spindle head can moving 1.5 degree angle. It is operate electric and air compressor mechanism.

5 degree FAHR change = 0.0001 inch

Main parts: Grinding wheel, grinding head and air compressor

Comments

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Why a dc generator fails to build up voltage?

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what is the difference between long shunt and short shunt dc generator?

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Various Methods of Drawing Flow Nets

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Which type of Battery connection Series or Parallel Connection is used for Diesel Generator?

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“Equalizer connection is needed in lap winding armature but not in wave winding “ why ?

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