2.1 Centre Lathe

Play an AI-generated podcast conversation about this lesson

What is the main function of a lathe machine?

To measure the dimensions of the work piece

To shape metal using heat treatment

To remove material from a work piece to produce the required shape and size (correct)

To weld pieces together

Who is credited with designing the first screw cutting lathe?

Isaac Newton

Leonardo da Vinci

Henry Maudslay (correct)

Alexander Graham Bell

Which type of lathe occupies less floor space?

Horizontal lathe

Facing lathe

Vertical lathe (correct)

Roll turning lathe

What does a single purpose lathe typically do?

Perform only one type of operation on limited ranges of size and material of jobs Signup and view all the answers

What was the significance of Egyptian tree lathes in the history of lathes?

They were the earliest known form of lathes Signup and view all the answers

Why is a single point cutting tool generally used in lathes?

To efficiently remove material during turning operations Signup and view all the answers

What is the primary function of the headstock in a centre lathe?

Transmit power and rotation to the job Signup and view all the answers

In a centre lathe, what is the function of the tailstock?

Support the workpiece with a center Signup and view all the answers

Which lathe type is suitable for fast and mass production of small size and simple shaped jobs?

Multi-spindle lathe Signup and view all the answers

What distinguishes flexible automation lathes from fixed automation lathes?

Type of automation Signup and view all the answers

Which part of a centre lathe supports the cross slide, compound rest, and tool post?

Saddle Signup and view all the answers

What is the primary function of the carriage in a centre lathe?

Give various movements to the tool Signup and view all the answers

Which type of lathe is suitable for holding slender rod-like jobs in collets?

Bar type lathe Signup and view all the answers

What distinguishes semi-automatic lathes from non-automatic lathes?

'Degree of automation' Signup and view all the answers

Which part in a centre lathe can be moved by hand or given power feed through apron mechanism?

Cross-slide Signup and view all the answers

What distinguishes precision lathes from ordinary lathes?

According to precision Signup and view all the answers

What is the term used for the lower part of the carriage that contains gears, clutches, and levers?

Apron Signup and view all the answers

In a lathe, what is the term for the movement of the tool relative to the work piece?

Feed Signup and view all the answers

Which feed type involves the tool moving parallel to the axis of the lathe?

Longitudinal feed Signup and view all the answers

What mechanism is used to move the carriage or cross-slide for various operations except thread cutting?

Feed rod Signup and view all the answers

When is the lead screw brought into operation in a lathe?

Only for thread cutting Signup and view all the answers

Which motion in lathes is attained by rotating the job?

Cutting motion Signup and view all the answers

How does the cutting tool derive its automatic feed motion in a lathe?

From spindle rotation via gear quadrant Signup and view all the answers

Which mechanism is used to change the feed rate in a lathe as needed?

Norton gear and Meander drive systems Signup and view all the answers

What type of headstock driving mechanism is used to reduce spindle speed for thread cutting?

Back geared headstock Signup and view all the answers

What is used to positively cause travel of the carriage during screw threading in a lathe?

Half nut engagement Signup and view all the answers

What is the purpose of the quick-change gearbox in the lathe?

To provide various power feeds Signup and view all the answers

How many different speeds can Shaft C receive in the quick-change gearbox?

36 Signup and view all the answers

In the tumbler gear quick-change gearbox, how are various speeds obtained?

By sliding the sliding gear to different positions and engaging the tumbler gear Signup and view all the answers

What is the function of the apron mechanism in the lathe?

To provide automatic feeds through the feed rod Signup and view all the answers

How does the splined shaft in the apron mechanism function?

To engage gears F and G with H and K Signup and view all the answers

What happens when the feed check knob 'E' is in a neutral position?

Gears F and G have no connection with H and K Signup and view all the answers

In what direction does the lead screw rotate in relation to the spindle?

In the opposite direction Signup and view all the answers

What is connected to Shaft C in the quick-change gearbox?

Lead screw by a clutch and feed rod by a gear train Signup and view all the answers

What is attached to Shaft B (Sliding gear shaft) in both gearboxes?

A gear receiving different speeds from Shaft A by sliding gear Signup and view all the answers

How are different sizes of gears transmitted to Shaft A (Cone gear shaft) in both gearboxes?

Through a cone gear from Shaft B's sliding gear Signup and view all the answers

What is the purpose of the back gears B1 and B2 in a lathe?

To reduce the speed of the spindle when engaged Signup and view all the answers

Which statement is true about the all geared headstock in modern lathes?

It eliminates the need for belt shifting. Signup and view all the answers

In a lathe, what is the main function of feed mechanisms?

To transmit power from the spindle to the carriage Signup and view all the answers

What happens when the tumbler gear mechanism is shifted to its upward position during lathe operation?

The lead screw rotates in the same direction as the spindle. Signup and view all the answers

Which component in a lathe is responsible for power transmission from motor to spindle through a belt drive?

Splined shaft Signup and view all the answers

How are different spindle speeds achieved in an all geared headstock in modern lathes?

By shifting levers into different positions to obtain gear combinations. Signup and view all the answers

What is the advantage of using an all geared headstock compared to a cone pulley mechanism?

Wider range of spindle speeds is obtained. Signup and view all the answers

'When back gear is not engaged' in a lathe, what type of speed is obtained at the spindle?

'Direct speed' Signup and view all the answers

What mechanism is used for automatic longitudinal feed in a lathe machine?

Tumbler gear mechanism Signup and view all the answers

How is automatic cross feed achieved in a lathe machine?

Power transmission through gears F and K Signup and view all the answers

Which mechanism allows for the reversal of both longitudinal and cross feed in a lathe machine?

Bevel gear feed reversing mechanism Signup and view all the answers

What is the purpose of using a half nut lever in a lathe machine?

To engage the half nut for thread cutting Signup and view all the answers

Which chuck type is commonly used for holding non-circular bars in a lathe machine?

4 jaw independent chuck Signup and view all the answers

What provides magnetic power to the magnetic chuck in a lathe machine?

Electro-magnet Signup and view all the answers

What is the purpose of drills and reamers when used in the tailstock of a lathe machine?

Enlarging and finishing holes Signup and view all the answers

What is the purpose of using a catch plate or driving plate in a lathe?

To drive the work piece through a carrier or dog Signup and view all the answers

How are carbide, ceramic, and cermet inserts clamped in the tool post?

Mechanically clamped in the seat of steel bars Signup and view all the answers

Why are mandrels made of high carbon steel?

To avoid distortion and wear during machining Signup and view all the answers

Which type of cutting tool is mainly used for general purpose work in center lathes?

Single point cutting tool Signup and view all the answers

Which type of centre is preferably used to avoid sliding friction between the job and the centre?

Revolving centre Signup and view all the answers

How are solid tools described in terms of material and manufacturing process?

Manufactured from high carbon steel through grinding Signup and view all the answers

In a lathe, what is the purpose of a tipped centre?

To increase wear resistance Signup and view all the answers

What is the primary advantage of fastening tips mechanically to a carbon steel shank rather than brazing them?

Increased rigidity Signup and view all the answers

When holding long slender rods in between live and dead centres, what is used to transmit torque and rotation from the spindle to the job?

Lathe dog or catcher Signup and view all the answers

What is the function of a steady rest in a lathe setup?

To prevent deflection of long slender jobs due to cutting forces Signup and view all the answers

In precision boring in a center lathe, where may the boring tool be fitted for support?

Tailstock quill Signup and view all the answers

What is the main purpose of a follower rest in lathe operations?

To move along with the cutting tool during long straight turning Signup and view all the answers

Why are ball centres specifically suitable for taper turning?

They have ball shaped ends to minimize wear and strain Signup and view all the answers