TABLE OF CONTENTS Creep-feed grinding utilizes very slow (creep) workpiece velocities and extremely large depths of cut. Straight surface grinding under creep feed conditions allows for much faster removal rates than can be reached with regular shallow cut grinding without causing thermal damage to the workpiece, even though creep-feed grinding generally requires much bigger specific energies. For creep-feed grinding of steels, the specific energy may substantially exceed the threshold value for workpiece burn as obtained for regular grinding in Chapter 6, but with no evidence of any thermal damage.
It has been suggested that the improved thermal situation in creep-feed grinding can be attributed to the extremely large depths of cut, such that much of the heat input to the workpiece is removed together with the grinding chips before it can be conducted out of the path of the advancing wheel [2]. This is somewhat analogous to the thermal situation with abrasive cut-off as described in the previous chapter. In order to evaluate this effect for creep feed grinding, the heat transfer analysis (section 6.2) was modified to take into account the large depth of cut by using an inclined heat source as illustrated in Figure 7-1 [3]. For this thermal analysis, the circular arc of the grinding zone was approximated by a chord AB oriented at an angle ? to the direction of workpiece motion. The heat flux was considered to be uniformly distributed over the source length AB, with the material from the workpiece crossing AB being removed...
