For stationary dressers and form rollers, depth of dressing cut, aed, defines engagement depth of the dressing diamonds with the grinding tool in normal direction. For profile rollers radial dressing feed, frd, has the same implication. Grinding wheel wear and grit size define the depth of dressing cut [AVER82]. The depth of dressing cut should […]
Рубрика: Life Cycle and Sustainability of Abrasive Tools
Implications of the Track-Bound Principle
Having chosen the track-bound principle for force generation, the functional requirements arise to hold the workpiece, provide the cutting speed and feed of the grits, and reduce the mechanical impact that is not crucial for the cutting action (Fig. 7.17). The workpiece can be held by mechanical or magnetic clamping, or the centerless principle can […]
Future Prospectives
From the time we enter the world with the help of medical instruments, until our final tombstone, polished to a glittering hardness, we live in the shadow of the grinding wheel. Name the product. Somewhere there lurks an abrasive operation; this has been so since the cave man, millions of years ago sharpened his tools […]
Comparison of Sintered Corundum and Molten Corundum
The most dramatic differences in performance occur between the grinding behavior of molten and sintered corundum. The introduction of sintered corundum led to tremendous tool life enhancements. The higher wear resistance and larger material removal rates of micro crystalline corundum compared to molten corundum results not only from the higher toughness of the abrasive material […]
Chemical Processes
The abrasives are processed chemically with acids and water damp to obtain wanted size, shape, and purity. SiC is washed with alkali or acid to remove adhesions of silicon, metals, metal compounds, graphite, dust, and SiO2 [LIET08]. Diamonds undergo an etching process to roughen their surface [MARI04]. Some abrasives like white corundum undergo special treatments […]
Other Analyses
Grit hardness is usually tested by a Knoop micro indenter test [SCHT81, MENA00]. By means of an electrostatic separator, particles with conductive surfaces can be selected. Capillarity is a measure for the wettability of abrasive grits [UAMA09, SCHT81]. Capillarity gives an indication of grit cleanliness and is particularly important for aqueous glues for coated abrasive […]
Manufacturing of Vitrified Bonds
First, the bond components and abrasives are mixed and filled into a mold, either by a casting process in the case of clayey bonds or by a molding process (Fig. 3.11). Pressing compacts the material and produces the so-called “green body” which can be handled. The green body is dried and sintered. After that, the […]
Sustainability Dimensions to the Bonding System
3.6.1 Technological Dimension Bond composition and structure define the self-sharpening ability of the tool and process stability. The main bonding systems for grinding tools are resin, vitrified and metallic bonds (Table 3.2). Each type has a huge variety in its specifications, manufacturing, and ingredients. For polishing and lapping processes also different kinds of slurry or […]
Other Methods with Free Abrasives
4.7.1 Crushing In the materials processing terminology, particle size reduction by mechanical means is called grinding [HOGG01, LYNC05]. Other terms are crushing, milling, or attrition milling. The term crushing is used for bigger end size particles (e. g. about 13-19 mm in diameter); the term milling refers to low micron sizes or below. Machines used […]
Clamping and Balancing
5.2.1 Flanges Cylindrical grinding wheels are often mounted on a hub and clamped between flanges [ROWE09, p. 49]. The adapter flange consists of a fixed flange, a lose flange, and head screws [DIN06]. Standards define the flange design, e. g. BS 4581:1970, and DIN ISO 666 [DIN06]. Some flanges have special features such as a […]