Correct cut with CARB^®

Using its toroidal roller bearing CARB, SKF has redesigned the spindles of a type of high–precision wire saw machine. These machines are used to cut mono–crystal material into wafers with a thickness down to 15 microns. The machines have a grid of fine wires running around three or four spindles, and the spindles must run smoothly to get the required precision.

   The original spindle design featured a cylindrical roller bearing in the non–locating position. This bearing often failed because of excessive edge load on the rollers, due to misalignment. In cooperation with the manufacturer of the silicon wafers, Czech company Trimex Tesla, SKF redesigned the spindle to include a CARB toroidal roller bearing in the non–locating position.

   Major improvements were noted when the redesigned wire saw machines were put in operation again. The reject rate decreased by more than 50 percent, bearing service life virtually doubled and maintenance costs decreased.