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 ?
We kept experiencing vibration which would cause the boring bar to break," explains Jamison.
The new boring bars offer the ability to quickly convert an endmill holder to an adjustable boring bar, and are available in four shank sizes: 5/8", 3/4", 1", and 1-1/4" diameter for both triangular and 80[degrees] diamond inserts.
Tenders are invited for Set Of Extra Long Finish Boring Bar
Included in the standard package are 10 different sizes of OD turning VM 63 tools, four different sizes of grooving and cutoff tools, nine different end mill adapters, eight different turning adapters, four different ID boring VM63 tools, five different boring bar adapters, three different shell mill adapters, eight different collet chuck adapters, two different tap adapters, two hydraulic chuck adapters, one extension, and three different reducers, and a complete supply of carbide cutting tool inserts.
boring bar of iso designation s16r sclcl 09 f3 or equivalent.
Tenders are invited for Supply Of Solid Carbide Boring Bar
Using a conventional boring bar saved money and allowed the finished product to be delivered within a short amount of time.
Limited Tenders are invited for Tool Holder Boring Bar Spares
The barrel is placed in a boring machine specially built for rigidity to prevent vibration while a long boring bar and special boring head are used.
Sharma et al [3], simulate the boring bar as a cantilever Euler-Bernoulli beam considering its first mode of vibration.