B.T. INSTITUTE OF RESERCH & TECHNOLOGY SAGAR (M.P.) SEMINAR ON “LATHE MACHINE” 2010-2011 SUBMITED TO- SUBMITED BY- Jimi Sirwani Mechanical Engg.(IIIrd sem.) Roll No. - 0608ME091033 Mr.Govind Kurmi Lecturer (Mechanical Engg. dept.)

LATHE MACHINE

INTRODUCTION Lathe is one of the most important machine tools in the metal working industry. A lathe operates on the principle of a rotating workpiece and a fixed cutting tool. The cutting tool is feed into the workpiece, which rotates about its own axis, causing the workpiece to be formed to the desired shape. Lathe machine is also known as “the mother/father of the entire tool family”.

HISTORY The lathe machine is one of the oldest and most important machine tools. As early as 1569, wood lathes were in use in France. The lathe machine was adapted to metal cutting in England during the Industrial Revolution. Lathe machine also called “Engine Lathe” because the first type of lathe was driven by a steam engine.

INVENTOR OF CENTRE LATHE Henry Maudsley was born on an isolated farm near Gigghleswick in North Yorkshire and educated at University Collage London. He was an outstandingly brilliant medical student, collecting ten Gold Medals and graduating with an M.D. degree in 1857.

MAIN PARTS Lathe Machine is also known as “Centre Lathe”, because it has two centres between which the job can be held and rotated. The main parts of centre lathe are: Bed, Head stock, Tail stock, Carriage,etc

TYPES OF LATHE Engine Lathe The most common form of lathe, motor driven and comes in large variety of sizes and shapes. Bench Lathe A bench top model usually of low power used to make precision machine small work pieces. Tracer Lathe A lathe that has the ability to follow a template to copy a shape or contour.

Automatic Lathe A lathe in which the work piece is automatically fed and removed without use of an operator. It requires very less attention after the setup has been made and the machine loaded. Turret Lathe Turret lathe is the adaptation of the engine lathe where the tail stock is replaced by a turret slide(cylindrical or hexagonal). Tool post of the engine lathe is replaced by a square cross slide which can hold four tools. Computer Controlled Lathe A highly automated lathe, where both cutting, loading, tool changing, and part unloading are automatically controlled by computer coding.

ENGINE LATHE

LATHE OPERATIONS Turning: to remove material from the outside diameter of a workpiece to obtain a finished surface. Facing: to produce a flat surface at the end of the workpiece or for making face grooves.   Boring: to enlarge a hole or cylindrical cavity made by a previous process or to produce circular internal grooves. Drilling: to produce a hole on the workpiece. Reaming: to finishing the drilled hole. Threading: to produce external or internal threads on the workpiece. Knurling: to produce a regularly shaped roughness on the workpiece.

LATHE OPERATIONS

CUTTING TOOL

WORK HOLDING DEVICES (a) and (b) Schematic illustrations of a draw-in-type collets. (c) A push-out type collet. (d) Workholding of a part on a face plate.

TYPES OF CHUCK Three jaw chuck - Forholding cylindrical stock centered. - For facing/center drilling,etc. Four-Jaw Chuck - This is independent chuck generally has four jaws , which are adjusted individually on the chuck face by means of adjusting screws

Collet Chuck Collet chuck is used to hold small workpieces Thin jobs can be held by means of magnetic chucks. Magnetic Chuck Thin jobs can be held by means of magnetic chucks.

DANGERS Don’t touch cutter or chips while machine is running Make sure work is clamped tightly in chuck or collet. Be careful to stay clear of chuck jaws

SAFETY All lathe operators must be constantly aware of the safety. Handle sharp cutters, centers, and drills with care. Remove chuck keys and wrenches before operating. Always wear protective eye protection. Always stop the lathe before making adjustments. Know where the emergency stop is before operating the lathe. Correct dress is important, remove rings and watches. Do not change spindle speeds until the lathe comes to a complete stop.

CARE AND MAINTENANCE OF LATHE Lathes are highly accurate machine tools designed to operate around the clock if properly operated and maintained. Lathes must be lubricated and checked for adjustment before operation. Improper lubrication or loose nuts and bolts can cause excessive wear and dangerous operating conditions.

CONCLUSION Lathes are normally robust in construction and they will, with good care, last for many years. It is not unusual for instance to see good lathes still in uses that are 50 years old. To ensure good, accurate, trouble free use it is necessary that the correct maintenance routines are regularly carried out and that important surfaces such as slide-ways are kept well protected so as to reduce wear and thus maintain good accuracy, and the lubricants used, are all factors that require your attention.