Хонинговальные головки

17.1 THE BASIC PROCESS 17.1.1 Introduction External cylindrical grinding refers to the grinding of an outer surface of a workpiece around an axis of rotation with the part held between centers. The surface may be a simple straight diameter or stepped, tapered, threaded, or profiled [Marinescu et al. 2004]. The grinder may be configured for […]

The selection of grain type has a significant impact on wheel length. Specifying of the length of an alox or ceramic wheel is based on the recognition that there is a significant level of wheel wear for each part that is ground. The length of the wheel is, therefore, kept short and the wheel oscillates […]

The grinding energy to remove a volume of material is a measure of the efficiency of material removal. The specific energy is given by P ec = Q (19.11) Specific energy is a measure of the difficulty of grinding a work material under particular grinding conditions. Hard materials give rise to higher specific energy than […]

The process limits define the permissible range of speed conditions for stable grinding. Typical process limits are shown in Figure 19.23. Two examples are illustrated for a 75-kW centerless grinding machine. The gray cast iron is an easy-to-grind work material and specific material removal rates were achieved in excess of 40 mm[10] [11]/s. When grinding […]

The true depth of cut at any position в is the difference in workpiece radius at that position and the value of radius at the same position one revolution earlier. ae (в) = r (в) — r (в — 2n) (19.54) Similarly, the set depth of cut is the difference between the set reduction in […]

For the manufacturer producing components by the thousand and the millions, process control assumes great importance. In this situation, it is essential to produce components rapidly and be assured of good quality. It can be wasteful if the process goes out of tolerance, particularly if the situation is not quickly detected. The process control system […]

The strength of the grain wear process is related to the magnitude of the stress impulses of the abrasive interactions. As an example, Figure 9.4 shows the abrasive grains of a D126 St50 grinding wheel with a concentration of C90 during grinding silicon carbide. In the left part of the image, the wear is typified […]

10.10.1 Conventional Grinding In comparison to dry grinding and grinding with emulsions, lower temperatures were measured in grinding with oil [Dederichs 1972]. The capacity of the cooling lubricant to discharge heat from the contact zone can be affected by the occurrence of film boiling of the fluid in the contact zone, leading to an abrupt […]

In almost all grinding processes, coolants are used to reduce heat and to provide sufficient lubri­cation. These are the main functions of any coolant supply. Furthermore, the removal of chips and process residues from the workspace of the machine tool, the protection of surfaces, and human compatibility should be provided. Modern coolant compositions also try […]

14.2.1 History The word ceramic can be traced back to the Greek term keramos, meaning “a potter” or “pottery.” Keramos, in turn, is related to an older Sanskrit root meaning “to burn.” Thus, the early Greeks used the term to mean, “burned stuff” or “burned earth” when referring to products obtained through the action of […]