Transverse grinding

Transverse rupture strength versus uncut chip thickness for longitudinal and transverse grinding. (From Mayer, J.E., Jr. and Fang, G.P., NIST SP 847, 205,1993. With permission.)... 

For transverse grinding, i.e., when the grinding direction is perpendicular to the applied tensile stress, the flexural strength drops off when the wheel grit depth of cut, /imax/ is increased beyond a critical value. 

PGH Heal treated after parallel grinding TG Transverse ground TGH Heat treated after transverse grinding... 

TGE ELID ground with 6000 SD-CIB wheel after transverse grinding TEH Heat treated after ELID grinding... 

At infrared wavelengths extinction by the MgO particles of Fig. 11.2, including those with radius 1 jam, which can be made by grinding, is dominated by absorption. This is why the KBr pellet technique is commonly used for infrared absorption spectroscopy of powders. A small amount of the sample dispersed in KBr powder is pressed into a pellet, the transmission spectrum of which is readily obtained. Because extinction is dominated by absorption, this transmission spectrum should follow the undulations of the intrinsic absorption spectrum—but not always. Comparison of Figs. 10.1 and 11.2 reveals an interesting discrepancy calculated peak extinction occurs at 0.075 eV, whereas absorption in bulk MgO peaks at the transverse optic mode frequency, which is about 0.05 eV. This is a large discrepancy in light of the precision of modern infrared spectroscopy and could cause serious error if the extinction peak were assumed to lie at the position of a bulk absorption band. This is the first instance we have encountered where the properties of small particles deviate appreciably from those of the bulk solid. It is the result of surface mode excitation, which is such a dominant effect in small particles of some solids that we have devoted Chapter 12 to its fuller discussion. 

The grinding conditions used for finish grinding in this research are shown in Table 4.8 and Table 4.9. Table 4.8 is for the grinding conditions for RBSN ceramic and Table 4.9 is for the almnina ceramic. The grind directions were perpendicular to the direction of the tensile stress in the subsequent flexural strength test, which is groimd transverse to the length of the bar. 

When the rolling inclinometer is used, the longitudinal and the transverse profiles of the travelled surface is determined, from which the roughness of the new pavement is quantified in terms of selective roughness index. The results are displayed by the on-board computer screen and also road roughness/smoothness and must grind areas can be reported in printed graphical and tabular report form. For more details, see ASTM E 2133 (2009). 

Corrosion damage was limited to minor pitting of the bottom head in the deaerator vessel. Inspection of deaerator vessel B revealed cracking at one weld. Tray sections were removed from the deaerator vessel, and shell welds were grit-blasted. Except for the top head-to-shell weld in the deaerator, all internal welds in both B nnits were then ground smooth and magnetic particle inspected. Three transverse cracks were found at the bottom circumferential weld in the deaerator vessel. These were removed by grinding to a depth of 1.5 mm (0.06 inch). 

The uses of rail grinding have evolved. Originally a simple removal of corrugation, the operation came to include a planned correction of transverse profile, and later a treatment of the surface condition of the rail. Now, all three aspects are dealt with simultaneously in a common rail rectification... 

The relationship between production rates and the number of grinding units is subject to incremental effects. Crucial point is the number of facets that are necessary to describe the target transverse profile. If a given machine is equipped with fewer units than the F pattern calls for, then it is not possible to finish the rail in a single pass. And the need for a second pass may depend on a marginal increment only. In practice, there are other considerations, such as the state of the rail in the longitudinal plane, so that one-pass grinding rarely takes place in Europe. 

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