Resumo

COLQUE C, Alejandro; CORIA C, Alfredo; GODOY R, Juan M  e  VERGARA D, Jorge. BILL MUNDY THEORY. SPECIAL DRILLS AND TAPS TOOLS IN COPPER MACHINING. Ingeniare. Rev. chil. ing. [online]. 2008, vol.16, n.1, pp. 181-187. ISSN 0718-3305.  doi: 10.4067/S0718-33052008000100007.

Copper drilling produces plastic and continuous chip. Bill Mundy a North American engineer developed a method who allows determines experimentally the best cutting angle material machining. Drilling and threading processes has several aspects in common.  New tools design, new materials, new techniques, new lubrication and cooling improvement, involve new different cutting rate and feed, parameters that should be necessarily studied to power, and time operation reduction for increase the edge cutting life and improving the finish surface.  In this work tensile strength test was made in copper, through the results the cutting angle was found according the Bill Mundy theory. Lately new test bars were cut and were perforated with drills type H, N and W, with external refrigeration, internal refrigeration, and dry. Tap for machining tools with two or three helixes were used. For each test was registered the cutting  speed, feed, cutting forces, torsor moment and power consumption.  It was verified that in the copper drilling, that a bigger helix angle facilitates the shredded of the chip and reduces the torsor moment.  Drills with internal cooling system can work with higher cutting speeds improving surface quality than tools with externally cooling system. Drills and taps with angle near the experimentally calculated according to the Bill Mundy theory show a good behaviour in the drilled process and also small power consumption.

Palavras-chave : Copper; drilling; tools; taps and tap form.