An integral part of Tube Hollows International’s services lies in our ability to perform centerless grinding in-house. Often, incoming tube hollows and barstock have dimensional tolerances that require further processing using centerless grinding. This precision process brings the materials into compliance with our customer’s specifications, thereby yielding the most uniform walled parts. Tube Hollows International routinely processes barstock OD dimensions to +/- .001" or better and round within .001". See this article about centerless grinding in Modern Machine Shop Magazine.
Centerless grinding differs from other precision machining in that the part to be machined is not held by a machine head or collet. Instead, the part rests freely between two wheels and is positioned atop an angled workblade. Using liberal amounts of lubricant, the smaller, rubberized regulating wheel rotates at slower speeds, while the larger grinding wheel spins at higher speeds. Material is removed slowly and accurately from the outer diameter of the machined part by the workblade, which also acts as a guide for the operator. Operators must take care to set blade height and grinding wheel speed correctly for the metal they are grinding, and consistently true the regulating wheel.
Although the lack of a holding device and measureable center makes centerless grinding counterintuitive to some, in the hands of the experienced operators at Tube Hollows International, centerless grinding becomes an ideal process which greatly improves the outer dimensional tolerances of out-of-round workpiece blanks, and gives our customers the precise roundness, surface finish and outer diameter dimensional tolerances they require in their finished tubing products.
Tube Hollows International has experience centerless grinding a wide variety of exotic metal alloys, and our world-class machinists have the know-how to adjust centerless grinds for soft or extremely hard metals, from aluminum to nitinol to 17-7 PH stainless steel. Tube Hollows International’s staff understands the delicate balance of centerless grinding, and how best to use the process to remove material from the outer dimension of your workpiece. By ensuring the grinding wheels, workblade and tube stock work together in perfect alignment, you can be assured of a final product that meets the most exacting engineering tolerances.
If you have any questions regarding centerless grinding for a project of any size, we would be happy to answer your questions and help make your project both cost effective and highly accurate.