Tech Talk
What is “Speed-Feed Grinding”?
Speed-feed grinding is a most under-utilized process. It is a reciprocating grinding process, however, instead of the table running on at the end of each stroke, the table position end-stops are very carefully controlled, so that every table reversal takes place at precisely the same point. One of the main disadvantages of reciprocating form grinding is that the impact of the grinding wheel and the workpiece, for each stroke of the machine and for every part, severely chips away any precise form dressed onto the wheel periphery. Speed-feed grinding is an attempt to overcome that disadvantage. First, only one part is machined at any one time. The machine table is driven by a rigid toothed belt system, so that the position of the table reversals can be accurately controlled. The process is therefore set up so that the grinding wheel never leaves the surface of the workpiece and suffers no impact forces. The table oscillates at a very fast rate, down-feeding at the end of each stroke just as the wheel is about to leave the surface of the workpiece.
This is a fast process and economizes on wheel usage. The types of parts suited to this process, however, are small, low mass parts, and those which are relatively short in table travel, eg., cutting tool inserts, fuel control arms, and parts with a large depth/length of cut ration.
