Boring Bar

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Related to Boring Bar: Boring Head

boring bar

[′bȯr·iŋ ‚bär]
(mechanical engineering)
A rigid tool holder used to machine internal surfaces.

Boring Bar


a device for boring holes; it is in the form of a cylindrical spindle with radially placed holes, either rectangular or round, in which individual or block cutters are fastened. Boring bars usually have a shaft that is fastened to the spindle of a boring machine. If the bar is long, the opposite end is held and guided by a sleeve on an end support. If the workpiece is fastened to a fixture rather than to the machine itself, the boring bar is directed by jig bushings, and the connection of the boring bar to the spindle is made with a coupling permitting self-alignment of boring-bar axis.

Various boring bars are designed to permit radial feed of the cutters for adjustment—that is, for compensation of the dimensional wear of the cutters—or the machining of indentations and grooves. Boring bars may be equipped with vibration dampers to reduce the level of vibrations arising in the cutting process.

References in periodicals archive ?
For example, a desire of being able to perform a cutting operation into pre-drilled holes in a workpiece limits the diameter or cross-sectional size of the boring bar during boring when the vibrations are a cumbersome part of the manufacturing process [9].
The new Digital Bore Measuring Tool is designed to work with boring bars from 1.
A tool changer sits below the spindle for switching boring bar assemblies.
For example if using a 0[degrees] or -1[degrees] lead angle boring bar (common to triangular inserts) --try changing to a -5[degrees] lead boring bar (common to 80[degrees] diamond inserts).
The line boring bar moves through the bushings' inner diameter and--with the help of precision bearings--rotates without friction.
For example, rather than employing a special line boring tool--which is both expensive and requires development and delivery time--they were able to do the required machining with a standard boring bar.
Using a carbide-inserted boring bar, I took the spade-drilled holes up, and increased the surface quality and size.
We kept experiencing vibration which would cause the boring bar to break," explains Jamison.
Tenders are invited for 20 Mm Dia Anti Vibration Boring Bar Length 200 Mm (570-3C 20 200).
The Jet-Stream[TM] high-pressure air or liquid coolant-through toolholder and boring bar system features clamping that not only holds but, controls air velocity or coolant flow in the system.
5" boring bar and produced parts at a cycle time of 105 minutes or three parts per shift.