A machining process is an interaction of geometric, kinematic and dynamic, physical, chemical, and tribological phenomena. It is not necessary to fully understand all these interactions to achieve a satisfactory process, but it is necessary to be aware of the factors that can influence the outcome and seek to determine best practice for each part […]
Рубрика: Handbook of Machining with Grinding Wheels
Increasing the Number of Active Grits
The main route to increasing removal involves increasing the number of abrasive grains that remove material within the grinding period. The number of active grits can be increased by: • Increased grinding wheel diameter • Increased grinding wheel width • Increased grinding wheel speed A larger number of active grits means more material can be […]
Workpiece Movements
This discussion deals only with the case of plunge feed, although the analysis has significance also for through-feed. Figure 19.34 defines position on the workpiece. A line of origin OX can be considered to rotate with the workpiece. Positions on the workpiece surface are defined by the angle from the line of origin. The position […]
Selection of Dresser Speed
The modern practice in precision grinding particularly when using superabrasive grinding wheels is to employ a motorized rotary dressing tool. The tool usually consists of a diamond-faced disc with a narrow cutting edge. A rotary disc is far more durable than a single-point diamond and a precision disc allows excellent rotational accuracy for precision dressing. […]
Adhesive Wheel Wear
Adhesion wear is based on an atomic bond at a microcontact surface between the active partners of the wear process through microwelding. This bond is very strong, which means that shearing through the relative movement of the active parts takes place at a different place than that of the original microcontact surface. Chemical adhesion is […]
The Jet Nozzle
At present, the most common type of cooling lubricant nozzle is the free jet nozzle aimed at flooding the entire contact zone. Being rather simple in design, this nozzle type is oriented in the tangential direction to the grinding wheel. In addition, the nozzle outlet should be positioned very close to contact zone. By varying […]
Noncontact-Based Workpiece Sensors
All the mentioned restrictions of contacting sensor systems on the workpiece surface gave a significant push to develop noncontact sensors. As for grinding wheels again, optical systems seem to have a high potential. In Figure 11.22, different optical systems as well as two other noncontacting sensor principles are introduced. A laser-scanner is shown as a […]
Grinding of Ceramics
14.1 INTRODUCTION This chapter discusses factors affecting the grinding of the new generation of hard engineering ceramics. Particular attention is drawn to effects on predressing time and surface quality. Electrolytic in-Process Dressing (ELID) grinding is introduced as an exciting new process used for machining a range of very hard materials and, in particular, for machining […]
SLIDEWAY CONFIGURATIONS 15.4.1 Introduction
Slideways traditionally refer to a range of linear sliding contact guideways based on square, T, or flat and V cross sections. In recent decades, the advent of NC and CNC machines has led to rolling element slideways for ease of positional control. Table way Hand-s V and fl Base cast FIGURE 15.6 […]
Hydrostatic Spindle Bearings for Large Wheels
For applications demanding the greatest stiffness, damping, and power handling requirements with minimal runout, many machine tool builders choose hydrostatic bearings. A hybrid hydrostatic bearing can provide greater load support than many hydrodynamic bearings of the same diameter and can withstand crashes better than other bearing types; a significant issue when using steel — cored […]