Рубрика: Manufacturing Processes 2

Kinematic Principles

The principles of the honing process will be explained using the example of short — stroke honing. The movement between tool and workpiece can be divided into three orthogonal speed components (Fig. 7-1): • two components parallel to the workpiece surface (axial feed rate vfa, tangential feed rate vft) • one component perpendicular to the […]

Lapping and Polishing

8.1 Lapping Lapping is a mainly room-bound process with geometrically undefined cutting edges. It is a production and finishing process, respectively, defined as chipping with loose grains distributed in a fluid or paste (lapping slurry) which are guided with a usually shape-transferring counterpart (lapping tool) featuring ideally undi­rected cutting paths of the individual grains [DIN78a]. […]

Polishing Fluid

The spectrum of tasks the polishing fluid must fulfil comprises supporting possi­ble chemical reactions, regulating heat, reducing the adhesion of the active part­ners involved in the process, and finally the distribution and transport of the abra­sive. Chemical-mechanical polishing processes are strongly dependent of the pH value of the polishing fluid. When polishing copper, for example, […]

Collision Monitoring

In the case of collision between the grinding wheel and the workpiece or other machine components, the motor current and acoustic emission increase to levels that are usually more than three times the amplitude of rough grinding processes. What must be evaluated is the acoustic emission or the effective current of the grinding wheel drive. […]

Honing Tools and their Preparation

Honing tools must be prepared prior to their first use. This operational step is a key determinant of the machining process and of a tool’s technological and eco­nomic performance. 7.2.1 Honing Stones with Corundum or Silicon Carbide Honing tools with conventional abrasive grains receive their desired form through mechanical material removal. Since narrow honing stones […]

Fundamentals

In lapping, the work surface rubs against the workpiece surface to be processed. Machining is achieved by means of the insertion of a lapping slurry (lapping grains and fluid) into the working gap between the machining disc (the tool) and the workpiece. In the process, loose grains (cutting edges) are added either con­tinually or intermittently. […]

Special Methods

9.1 Abrasive Blast Cutting According to DIN8589 [DIN78a] abrasive blast cutting is to be classified with the group machining with geometrically undefined cutting edges. In contrast to other methods in that category such as grinding, honing and lapping, it is used for a tar­geted influence of the surface layer. From this angle, it has gained […]

Dressing Monitoring

The dressing process creates the grinding wheel shape and topography required for the respective machining task. Fluctuations of the actual depth of dressing cut, temperature drift of the machine axes relative to each other and further sources of disturbance cause dressing errors and thus fluctuations in workpiece quality as well. In order to guarantee a […]

Gear Honing

Gear honing is a finishing method for gears which was originally employed after grinding in order to produce surface structures on the tooth flanks favourable to noise emission. Small stock allowances of about 15 pm would be removed from the flanks. As the process developed further, it was able to be utilized directly af­ter hardening, […]