Хонинговальные головки

Due to strain, steels destined for roller bearings have a high level of hardness (52 — 65 HRC), a high degree of purity, an even structural configuration and high resis­tance to wear. Chemical composition, melting and heat treatment are decisive for the obtainable structure and thus for the necessary properties of roller bearing steels. In […]

In the grinding process, all the components involved — the grain material (includ­ing the bond) as the body, the workpiece material as the counter-body, cooling lu­bricant as the intermediate substance and air as the environmental medium — form a tribological system (Fig. 5-1). Thus, in order to optimise the cooling/lubrication system, all components involved as […]

Working with materials that are hard to machine generally causes problems with respect to the lifetimes of the grinding wheels used and thus with respect to the performance of the grinding process. Large amounts of grinding wheel stress lead to increased grain breakaway, especially in the case of conventional grinding wheels. Grinding wheel wear, which […]

Among cylindrical grinding techniques, centreless methods have an exceptional position with respect to their process structure and area of application. Centreless grinding’s main area of use is in large batch and mass production. While the workpiece is led during grinding between centres in its rotation axis, its position in centreless grinding is determined by a […]

Knowledge of the basic principles of a machining method is an essential prerequi­site for the full realisation of its potential. Yet research into the essential features of material removal with geometrically undefined cutting edges is beset with great difficulties. The determination of the cutting edges used in the procedure is ham­pered by the extremely complex […]

The resin bond consists of a synthetic resin or synthetic resin combination with or without fillers. For particular grinding wheel types, applications or different fabri­cation methods, there are many resins available. In the case of the dry mix method, phenol resol is used for the grit wetting as well as a phenol resin powder based […]

The production process in the manufacture of abrasive tools starts with the back­ing material. This is furnished with a corresponding base binding, and, after apply­ing the abrasive grits, the top bonding layer is laid on. Backing Material Depending on the expected thermal and mechanical strains, paper, fabric, vulcan­ized fibre or combinations of these materials are […]

Tool steels are generally subdivided into • unalloyed tool steels and • alloyed tool steels. These are utilised for varied purposes. Therefore tool steels are further differen­tiated into the particular application groupings of cold working steels, hot working steels and high speed steels. The assignment of any steel to a tool steel group re­sults only […]

The properties of cooling lubricants and the demands placed on them are manifold (Fig. 5-2). Not only technical performance, but also economical, ecological as well as safety and health concerns play a role. One of the most important physical properties of cooling lubricants is viscosity. This describes internal resistance of a fluid to deformation. Viscosity […]

A special case of dressing is crushing. The operating principle of crushing is based on the crushing of bond bridge when a certain force level on the grinding wheel coating is exceeded [DENN02]. This is achieved by pressing rollers on the grind­ing wheel layer without relative velocity (dressing speed ratio qd = 1). The crushing, […]