Figure 15.56 shows a traverse diamond roll unit with a small double-barrel stepper motor infeed and a dc motor cross-slide and DFW-HTG spindle. This carrier is designed for traverse dressing of CBN and engineered ceramic wheels. 15.18.9 Plunge-Roll Infeed System for a Creep-Feed Grinder Figure 15.57 shows a plunge roll infeed system for a Brown […]
Рубрика: Handbook of Machining with Grinding Wheels
Creep Feed Grinding with CBN
Creep feed grinding with CBN can be divided quite definitively between plated CBN and vitrified CBN in terms of distinct machine conditions, coolant, and operating parameters. TABLE 16.8 Example of Removal Rates in the Viper Process for Grinding Turbine Blade Root Forms Pass Wheel Speed Table Speed Depth of Cut Dressing Depth Q’w (m/s) (mm/min) […]
External Cylindrical Grinding
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 […]
Impact on Grind Configuration
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 […]
Specific Energy
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 […]
Process Limits
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 Basic Equation for Rounding
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 […]
PROCESS CONTROL
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 […]
Wear of the abrasive grains
9.3.1 Types of Grain Wear Overlap between the above-mentioned wear mechanisms leads to changes in the abrasive grain. These wear types are depicted in Figure 9.2. They basically can be divided into [3] Process Tool Single grain force Grain holding force Load impulse Toughness of the bond Load direction // Flattening Heat conductance Contact zone […]
Through-the-Wheel Supply
A slightly different concept of lubricant distribution is the supply of cooling lubricant from the interior of the grinding wheel or the grinding layer. The fluid is fed into a chamber of the wheel body allowing the centrifugal force to distribute it through radial channels to the grinding layer. Through pores or gaps in the […]