---
title: "Classification and main parts of centre lathe"
subject: "Workshop Technology"
chapter: 6
key: "semester_2/workshop_technology:lathe-classification-main-parts"
source: https://www.bctengineer.com/q/semester_2/workshop_technology/lathe-classification-main-parts
site: BCT Engineering
---

# Classification and main parts of centre lathe

Workshop Technology · Chapter 6: General Machining Processes “Chip-forming”

- Asked in: year not given, 3+5 marks
- Video: [Lathe Machine: Parts, Function, Working, Operations & Types of Lathe Machine](https://www.youtube.com/watch?v=oUmzSB9TVgY) — The Engineers Post
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_2/workshop_technology/lathe-classification-main-parts
- Whole chapter: https://www.bctengineer.com/md/semester_2/workshop_technology/chapter-6

## Question

(a) Classify lathes. (b) With a neat sketch, name the main parts of a centre (engine) lathe and state the function of each.

## Short answer

Lathes are classified as speed, engine, bench, toolroom, capstan/turret, automatic, and special purpose. Main parts: bed (supports all), headstock (spindle and speeds), tailstock (support and drilling), carriage with cross-slide, compound rest, tool post, apron, feed rod and lead screw for turning and threading.

## Answer

#### (a) Classification of lathes
- Speed lathe: simple, 3 or 4 speeds, no feed or carriage; for wood turning, polishing, centring.
- Centre or engine lathe: general purpose, power feed, lead screw; most common in workshops.
- Bench lathe: small engine lathe mounted on a bench for light precision work.
- Tool room lathe: precision engine lathe with a wide speed range and many attachments.
- Capstan and turret lathes: hexagonal turret holds many tools for repetitive production of small parts.
- Automatic lathes: loading, feeding and tool change are automatic (cams); for mass production.
- Special-purpose lathes: wheel lathe, gap-bed lathe, T lathe, CNC lathe.

#### (b) Main parts of an engine lathe
```text
 headstock           tailstock
 +------+  chuck       __ quill
 |gear  |==[O]--job--<|__|
 +------+   tool post      
 =====[ carriage ]============ bed (ways)
  legs   apron   lead screw & feed rod
```
- Bed: heavy cast iron base with precisely machined ways on which carriage and tailstock slide; supports all parts.
- Headstock: fixed at the left end; houses the spindle, gear box giving different speeds, and carries the chuck or face plate.
- Tailstock: on the right; supports long jobs with a dead centre and holds a drill or reamer; its body can be set over to turn a taper.
- Carriage: slides along the bed; consists of saddle, cross slide, compound rest, tool post and apron.
- Apron: attached to the carriage; holds the gears and clutch for hand and power feed and the half-nut for thread cutting.
- Feed rod and lead screw: the feed rod gives power feed for turning; the lead screw (Acme thread) moves the carriage for thread cutting.
- Cross slide and compound rest: cross slide moves the tool at right angles to the axis (facing, depth of cut); the compound rest swivels for taper turning.
- Tool post: clamps the cutting tool.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. A lathe with only 3 or 4 speeds and no carriage or feed, used for wood turning and polishing, is a
   A. Speed lathe
   B. Engine lathe
   C. Capstan lathe
   D. Automatic lathe
   Answer: A. The speed lathe is the simple type with no power feed or carriage. (Key point: Speed lathe)

2. What is the main advantage of capstan and turret lathes?
   A. They are the cheapest lathes
   B. A hexagonal turret holds many tools for repetitive production of small parts
   C. They need no operator
   D. They cut only wood
   Answer: B. The turret carries several tools in sequence, suiting repetitive production. (Key point: Capstan and turret)

3. The headstock of an engine lathe
   A. Slides along the ways with the tool
   B. Houses the spindle and gear box and carries the chuck
   C. Supports long jobs with a dead centre
   D. Holds the cutting tool
   Answer: B. The headstock at the left end holds the spindle and speed gearing, and carries the chuck or face plate. (Key point: Function of the headstock)

4. Which statement is correct?
   A. The feed rod cuts threads, the lead screw gives power feed
   B. The feed rod gives power feed for turning, the lead screw moves the carriage for thread cutting
   C. Both do thread cutting
   D. Both are used for the tailstock
   Answer: B. Feed rod for turning feed; the Acme-threaded lead screw with the half-nut for threading. (Key point: Lead screw vs feed rod)

## Related in Workshop Technology

- [Work holding and tool mounting on lathe](https://www.bctengineer.com/question.md?key=semester_2%2Fworkshop_technology%3Alathe-work-tool-holding) — Workshop Technology, chapter 6
- [Thread cutting on lathe and change gears](https://www.bctengineer.com/question.md?key=semester_2%2Fworkshop_technology%3Alathe-thread-cutting-change-gears) — Workshop Technology, chapter 6

## Related in other subjects

- [Turbomachine: definition, parts and classification](https://www.bctengineer.com/question.md?key=semester_7%2Fturbo_machines%3Aturbomachine-definition-classification) — Turbo Machines, chapter 1
- [Significance of main() function](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Asignificance-of-main) — Computer Programming, chapter 6
- [Lathe operations, taper turning and turning calculations](https://www.bctengineer.com/question.md?key=semester_4%2Fmanufacturing_and_production_processes%3Alathe-operations-taper-turning-numerical) — Manufacturing and Production Processes, chapter 7
- [Alignment tests on a lathe](https://www.bctengineer.com/question.md?key=semester_3%2Fmetrology%3Amachine-tool-geometric-tests) — Metrology, chapter 13