Tech Talk
What is "In-Process Gaging"?
Cylindrical grinding is not only very precise and very accurate but also a highly productive process. Particularly with large batch production, there is a high demand to accurately measure the workpiece without removing it from the machine. In-process gaging principles have therefore been incorporated in the design of both the grinding machine and its control system.
The electronic signals from the gage head, which has two stylii touching the workpiece periphery, are fed back to the machine control in order to produce a diameter dependent, grinding wheel in-feed control. Parts may be ground very quickly with high quality, using this size control technique. The NC gaging head shown, is a development which allows the measurement of a range of diameters to be achieved without the task of manually setting the gaging unit. Gage setting and measurement is performed under numerical control. An important feature of such an in-process gage is that it has the ability to measure both plain and interrupted diameters. The gaging head is able to measure a plain diameter as easily as the diameter of a splined shaft.
A further feature incorporated in the in-process gaging unit is the ability to measure the part position length. This is an important feature, particularly for angle approach grinding where the machined form must be related to a shoulder on the workpiece.
Such systems of in-process gaging, linked with CNC controls are making cylindicral grinding machines more versatile and economical because the easy programming and quick setup also provides a significant saving in one-off and small batch production.