Boring Bars
An asymmetric line boring bar
Automaker BMW challenged the Kennametal Inc. to develop a tool that accentuates the advantages of reaming and line boring while virtually eliminating the disadvantages. Kennametal accepted the task and developed its asymmetric line boring bar, which has two guide pads positioned so they only contact the last journal. This enables the boring bar to be quickly fed in and out of the multijournal bore without touching the workpiece. This geometry allows the bar to be fed through the raw, or unfinished, bores on an eccentric path.