Sawing is one of the most important cutting operations that are performed in a manufacturing plant. Metal sawing is chiefly concerned with cutting bar stock to a convenient length or size for machining.
In sawing, the individual teeth of the saw "track" through the work, each tooth depending on the cut made by the preceding tooth in the feed direction. Either the saw or the work may be fed and, by controlling the direction of feed, either a straight or curved cut can be produced. The width of the cut is approximately equal to the width of the saw itself.
Types of Sawing Machine
Sawing machines may be classified by the motion used for the cutting action. Accordingly, the various types of sawing machines are listed below:
Reciprocating Sawing Machine
These types of sawing machines are represented by power hack saws. A power hack saw consists of a saw frame, a means for reciprocating the saw and frame, a work table and vise, a supporting base, and a source of power.
In operation, the machine devices a blade back and forth through a workpiece, pressing down on the cutting stroke and releasing the pressure on the return.
The down-feed force on the blade may be obtained from gravity or springs regulated by a ratchet mechanism, a positive feed screw, or a hydraulic device. The simplest type of feed is the gravity feed, in which the saw blade is forced into the work by the weight of the saw and frame.
A hydraulic or mechanical arrangement is also incorporated for lifting the blade on the return stroke. Many are crank-driven the large ones often are hydraulically driven.
The stock to be cut is held between the clamping saws. several pieces of bar stock can be clamped together and cut at the same time. both square and angular cuts can be made.