THE EFFECT OF NOZZLE TYPE AND ITS POSITIONING ON SURFACE INTEGRITY OF VP100 STEEL AFTER GRINDING
Rosemar Batista da Silva1; Cleudes Guimaraes1; José Renato Santos do Amaral Cardoso1; Armando Marques2; Antonio Vitor de Mello1; Raphael Lima de Paiva3
1 Universidade Federal de Uberlandia; 2 Federal Institute of Espirito Santo; 3 Federal University of Uberlandia
doi:10.20906/CPS/COB-2015-2459
Resumo
Grinding is a final machining process employed when smooth surfaces and closer geometric tolerances are required. Among the various parameters that can affect grinding performance, the cutting fluid and its delivery to the cutting zone play an important role because, depending on the wheel-workpiece system combination, it can represent up to 13% of the total cost of the process. Thus, in order to achieve the best benefit-cost relation for any specific case, it is important to investigate, in addition to the cooling delivery technique, how variation in nozzle geometry and its positioning in relation to wheel-workpiece interface can contribute to improve the grinding efficiency. Into this context, this paper presents a study on grinding of ABNT VP100 mold steel employing two types of nozzles (metal shoe geometry and plastic adjustable magnetic kit) and their positioning (jet tangential to the wheel and jet directly applied at the wheel. Experimental trials were carried out in a peripheral surface grinder. Three depth of cut values (20, 40 and 60 micrometers) were tested. Ra, Rq and Rz surface roughness were the output parameters analyzed. Results show that the lowest Ra values were obtained after grinding with the combination of metal shoe nozzle and jet directly applied at the wheel. This positioning was found to be more effective in cleaning of the abrasive wheel, therefore contributing to improve finishing. All surface roughness values increased with depth of cut, as expected.
Palavras-chave: grinding; nozzle type; nozzle positioning; surface roughness; cutting fluid