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Jig Boring Machine

Introduction of the jig boring machine:
A jig boring machine, often referred to as a jig borer, is a precision machine tool used in manufacturing and
toolmaking industries for producing highly accurate bores, holes, and contours with tight tolerances.

Working Principle of jig boring machine:
The working principle of a jig boring machine involves precise positioning and machining of holes, bores, and
contours in work pieces with exceptionally tight tolerances. The machine operates on the basis of accurate guiding
mechanisms and controlled movements to achieve the desired machining outcomes.
Parts of jig boring machine:
1 Base: The base of the jig boring machine provides a stable foundation and supports the entire machine
structure. It is usually made of heavy cast iron or steel to minimize vibration and ensure rigidity during machining
operations.

2 Column: The column is a vertical structural component mounted on the base and provides support for the
other machine components, including the spindle assembly and the cross-slide. It may feature guideways or
tracks to allow vertical movement of the cross-slide along the column.
3 Cross-Slide: The cross-slide, also known as the saddle, is a movable component that travels along the
column in the vertical direction. It carries the spindle assembly and allows for precise positioning of the cutting
tool relative to the work piece. The cross-slide may be equipped with hand wheels or motorized drives for
manual or automatic control of vertical movement.

4 Spindle Assembly: The spindle assembly houses the cutting tool and provides the means for rotating it at
high speeds. It typically consists of a spindle, bearings, drive mechanism, and tool holder. The spindle may
have provisions for vertical and horizontal movement to facilitate drilling, boring, and milling operations.
5 Table: The table is a flat, horizontal surface located below the spindle assembly and serves as the work piece
support during machining. It may have T-slots, clamping fixtures, or other means for securing the work piece
in position. The table can be adjusted vertically and horizontally to align the work piece with the cutting tool.
6 Tool Holder: The tool holder is a component that holds and secures the cutting tool in place during machining
operations. It may be a collet, chuck, or tool turret, depending on the type of tool and machining requirements.
The tool holder ensures proper tool alignment and concentricity with the work piece.

7 Control Panel: The control panel contains the machine’s control interface, including switches, buttons, and
indicators for operating the machine. It may include manual controls for adjusting spindle speed, feed rate, and
axis movement, as well as digital displays or readouts for monitoring machining parameters.
8 Coolant System: A coolant system is often integrated into the jig boring machine to lubricate and cool the
cutting tool and work piece during machining. Coolant helps reduce heat generation, chip formation, and tool
wear, resulting in improved machining efficiency and surface finish.
9 Power Drive Mechanism: The power drive mechanism provides the means for driving the spindle and
moving the cross-slide and table during machining operations. It may consist of electric motors, gears, belts,
or hydraulic/pneumatic systems, depending on the machine’s design and capabilities.
10 Guideways: Guideways are precision-machined surfaces that guide the movement of the cross- slide and table
along the column and base, respectively. They ensure smooth and accurate motion of machine components
and help maintain machining accuracy and repeatability.

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