Determinação do intervalo de máxima eficiência na usinagem de tambores de freio fundido cinzento SAE J431 G3500 com ferramentas de CBN

Abstract

This dissertation aims to identify the range of maximum efficiency in the machining of brake drums made from gray cast iron SAE J431 G3500. For this determination, distinct groups of brake drums were machined with cutting speeds of 800, 900, 1.000, 1.100, and 1.200 meters per minute. After the end of the tests, the wear that each CBN insert presented was identified, relating the number of machined brake drums with the cutting speed used, the time used, and the cost associated with the machining process. As a result, the economic machining condition could be determined when the cutting speed of 800 meters per minute is used, presenting a machining cost of $ 9,18 per machined drum. The maximum production condition was identified using a speed of 900 meters per minute, where it was possible to machine 29 brake drums per hour. With cutting speeds of 800 to 900 meters per minute, productive strategies must be used within this range to obtain maximum efficiency in the machining process of brake drums manufactured from gray cast iron, when using inserts of CBN. [resumo fornecido pelo autor]