Objective: To study about sawing machine
6.1 Introduction
Sawing is an important first operation carried out in a workshop for producing bar stocks for subsequent machining operations. Although sawing operation is often carried out on machine tools, but their application is restricted to small pieces to a limited extent. Special purpose machines are needed for the mass production of miscellaneous workpieces.
6.2 Parts of a hacksaw machine
- Bed : The bed is available as a single piece casting. it has wide rigid casting for the collection of coolant, Swarf and also houses the v-belt device.
- Saw Frame : The rigid saw frame ensures a square & parallel cut & the cut takes place on the backward pull stroke.
- The Drive : The drive is attached through v-pulleys with provision to adjust the complete tension of the v-belts.
Fig. 6.1 Power hacksaw machine
- Feed Saw : Two levers are provided to hydraulically control the feed saw at the dash spot. One control the rate of feed and the other enables the bow slide to be raised or lowered and after the completion of the cut, the motor gets automatically switched off.
- Vice : The vice is rigid construction. It has two jaws, one jaw remains fixed and the other is adjusted accordingly to the size of material to be cut.
- Coolant : A coolant tank is enclosed within the base of machines with constant speed to supply continuous cooling to the saw blade.
- Electricals : A Push Button Starter is fitted with an adjustable trip mechanism that helps in stopping the machine soon when the blade is clear from the work at extra cost.
6.3 Blade specifications
A power saw blade is specified by the
- Material of the blade
- Length of the blade
- Width of the blade
- Thickness of the blade
- Pitch of the teeth
6.4 Specification of Power Saws
A power saw machine is usually designated by the size of the bar stock that can be cut on it. It is mainly specified by the
- Length of the blade to be fitted on the machine
- Stroke length
- Number of strokes per minute
- Type of drive
- Power required for the machine drive
The specification of hacksaw machine manufactured by Kohinoor Engineering Works, Rajkot, India, is given below:
Table 6.1 – Specification of hacksaw machine manufactured by KEW
|
Description |
Dimension |
|
Cutting capacity |
170 mm |
|
Saw blade |
14 inch |
|
Motor |
1 H.P. |
|
V – belt |
B – 54 × A – 32 |
|
weight |
190 Kg |
ACTUAL JOB PHOTOGRAPHS