Nadolny K., Kapłonek W., Ungureanu N. | Journal of Mechanical and Energy Engineering, Vol. 1, No. 1, 2017, pp. 1-8 7

obtained for the process realized with the conic chamfer of the abrasive tool = 0.38°. This value of c the angle corresponds to the greatest chamfer width c b = 15 mm. This means that the even distribution of the total machining allowance on a greater area of the grinding wheel conic chamfer allows for more effective operation of the rough grinding zone. As a result, the shorter cylindrical part of the grinding wheel removes a smaller volume of the material, which further guarantees lower roughness of the machined surface.

traverse internal cylindrical grinding process along with a drop in the value of the grinding wheel conic chamfer value. The even distribution of the machining allowance over a greater surface of wider conic chamfer allowed for more effective removal of the material in the rough grinding zone and despite shortening of the cylindrical part of the grinding wheel contributed to improvement of the smoothness of the grinded surfaces. Simulta- neously, modification of the chamfer parameters did not have any significant influence on the grinding power. The obtained research results form the basis for determining recommendations in terms of the suggested width of the conic chamfer performed on the abrasive tools’ active surface in such grinding processes. It may be assumed that the chamfer width should equal 90% of the rough grinding zone width b = 0.9×T. Such a value allows for maximum usage of 1 the grinding wheel zone width designed with a view to intensive removal of material and leave a margin for motion towards the end of the chamfer in the direction of the cylindrical part, caused by progressive wear of the grinding wheel. The final value of the chamfer angle will result from the chamfer width b and the c working engagement value a. e

### Acknowledgements

Part of this work was supported by the Polish Ministry of Science and Higher Education under Grant No. N503 214837. The Author wish to thank Mr. Andrzej Nowicki from Laboratory Team I for his help during experimental investigations of the grinding process, Mr. Krzysztof Maciejewski from the Laboratory of Metrology And Measurement Systems for stylus measurements as well as Mr. Ryszard Gritzman from Central Laboratory of the Institute of Technology and Education for acquisition of SEM micrographs.

### Nomenclature

Fig. 8. Effect of the grinding wheel conic chamfer angle c on the grinding power P (a) and the grinding power gain DP (b)

Symbols ae – machining allowance (working engagement), μm b – conic chamfer width, mm bw – workpiece width, mm dw – workpiece diameter, mm id – number of dressing passes nsd – grinding wheel rotational speed while dressing, rpm P – grinding power, W Qc – coolant flow rate, l/min Qd – diamond dresser mass, kt Ra – arithmetic mean deviation of the assessed profile, μm Rz – maximum height of the profile within a sampling length, μm RSm – mean width of profile elements, within a sampling length, μm Rdq – root-mean-square (RMS) slope of the profile within a sampling length, °

### 4. CONCLUSIONS

The carried out research on the influence of the value of the grinding wheel conic chamfer angle on the roughness parameters of the machined surfaces and the grinding power prove that it is possible to optimize the conditions of the realization of the given process using angle c. It must be, however, noticed that precise realization of conic chamfer in the field of low values of the angle requires application of special device. The measured parameters of the geometric structure of the machined surfaces and the grinding power indicated, without any exception, that there was an improvement in the conditions of realization of the