Хонинговальные головки

In creep feed grinding, surface roughnesses are much smaller due to the engagement of a higher number of cutting edges and due to smaller feedrates than in the case of reciprocating grinding. Since the functional surface properties of a workpiece are often important, creep feed grinding has a clear advantage here. This can be traced […]

For manufacturers that choose to rough machine the part, Thielenhaus [n. d.] provides a grinder/superfinisher to microfinish the faces to create a good sealing surface. This is particularly suited for applications such as aluminum cylinder heads with hardened liners that create step problems for machining. The process uses small conventional abrasive segments in a rotating […]

Camlobe grinding has been the leading driver of high-speed grinding over the last 25 years. It is a high-cost process, making up more than 40% of total camshaft manufacturing costs [Wedeniwski 1989]. The operation is very capital-equipment intensive resulting in pressures from end users to reduce cycle times while offering machine tool builders sufficient end […]

This refers to a class of grinders that must have the flexibility to perform a range of grinding operations that may also include face and OD grinding in a broad range of parts. Multispindle (a) At load/unload position   (b) At grind position [Bryant (1995)]   FIGURE 18.22 Bryant UL2 loader for shoe centerless mode […]

A different problem can arise with heavy workpieces if there is insufficient control wheel friction to turn the workpiece on contact with the grinding wheel. Heavy workpieces are unlikely to suffer the problem of “spinning.” In fact, heavy workpieces are more likely to suffer the problem of failing to turn at all under the action […]

Direct-effect charts are the result of the experimental design described in Section 19.10.7. An example is shown in Figure 19.29. The example is for workpiece roughness in high-speed CBN grinding of AISI 52100. The results clearly show that high wheel speed reduces roughness. A chart for grinding ratio is shown in Figure 19.30 for the […]

Substituting s = jm in Equation 19.76, it is possible to solve the characteristic equation to find the unstable limit frequencies and the corresponding limits of grinding force stiffness at the threshold of instability. Noting that m = n. Q., the frequencies are given by where A and B are the real and imginary parts […]

The statement that a process can be controlled “within an acceptable range” requires some definition. A recent study by Hitchiner and McSpadden (2005) investigated the process variability of various vitrified cubic boron nitride (CBN) processes as part of a larger program to develop improved wheel technology. They showed that under “ideal” conditions repeatability of wheel […]

3.3.1 Introduction The determination of the grinding wheel topography can be divided into static, kinematic, and dynamic methods [Bruecher 1996]: • Static methods—All abrasive grains on the surface of the grinding tool are considered. The kinematics of the grinding process is not taken into account. • Dynamic methods—In this process, the number of actual abrasive […]

Chatter is visible down to displacements of 10 pin. Achieving displacements below this, even with the most sophisticated hydrostatic wheel bearings, is becoming increasingly more of a challenge as wheel speeds increase. For regular hydrodynamic or ball-bearing-based spindles, some form of dynamic balancer mounted to the machine is essential. Automatic balancers are mounted on the […]