---
title: "Short note: Grader and dragline"
subject: "Construction Management"
chapter: 4
key: "semester_8/construction_management:grader-dragline-note"
source: https://www.bctengineer.com/q/semester_8/construction_management/grader-dragline-note
site: BCT Engineering
---

# Short note: Grader and dragline

Construction Management · Chapter 4: Familiarization with Construction Equipments

- Asked in: 2074 Bhadra, 5 marks
- Video: [DRAGLINE as Construction Equipment //](https://www.youtube.com/watch?v=aGHOkUJuI7Y) — PM Home Tuitions 
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_8/construction_management/grader-dragline-note
- Whole chapter: https://www.bctengineer.com/md/semester_8/construction_management/chapter-4

## Question

Write short notes on grader and dragline.

## Short answer

A grader is a six-wheel finishing machine with a long adjustable blade used for fine grading, spreading, ditch cutting and road maintenance; it is not for heavy digging. A dragline has a bucket hung from a boom by hoist rope and pulled by drag rope, digging below its level for soft soil, canals and dredging.

## Answer

#### Grader (motor grader)
```text
         cab
      [_______]
   (O)|=======|(O)(O)    blade (moldboard)
         \_____/       under the frame, can swing & tilt
```
A grader is a six-wheel machine with a long adjustable blade (moldboard) between the front and rear axles. The blade can be raised, lowered, tilted and angled. Uses: fine grading of sub-grade and base courses to correct levels and camber, spreading and mixing materials, cutting side drains and ditches, snow and debris removal, and maintenance of unpaved roads. It is a finishing machine; it is not suited to heavy digging.

#### Dragline
**Dragline:** an excavator whose bucket hangs from a boom by hoist rope and is pulled toward the machine by a drag rope. It digs below the machine level and works at a distance from its own tracks.

```text
        boom
         /\
        /  \   hoist rope
   cab /____\    |
  ____|______|   v
  [==tracks==]   \__bucket-->(drag rope pulls bucket in)
```
- Parts: crawler base, cab/rotating deck, long boom, hoist rope, drag rope, bucket.
- Operation: the bucket is thrown out, dragged to fill, hoisted, swung and dumped.
- Uses: soft soil, sand, wet ground, canal and drain cleaning, underwater and river dredging, long reach digging and stockpiling.

## Check yourself

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

1. What does the grader blade (moldboard) allow?
   A. Only fixed forward
   B. Rotates 360 degrees
   C. Only vertical lifting
   D. It can be raised, lowered, tilted and angled
   Answer: D. The blade can be raised, lowered, tilted and angled. (Key point: Grader blade)

2. What is a limitation of the grader?
   A. It cannot level
   B. It needs rails
   C. It is a finishing machine not suited to heavy digging
   D. It cannot move
   Answer: C. Graders are finishing machines, not heavy diggers. (Key point: Grader limit)

3. Relative to the machine, where does a dragline dig?
   A. Only underground in tunnels
   B. Below machine level, at a distance from its tracks
   C. Above machine level only
   D. Only at machine level
   Answer: B. Draglines dig below machine level and work at a distance. (Key point: Dragline level)