摘要 |
<p>The method for obtaining expulsion tubulars where are guided the corresponding expellers used in moulds, for example injection moulds, comprises a series of operations which are carried out on a tube (1), the first operation consisting in cutting a portion of the tube (1) to the desired length, with an excess of diameter to allow for an eventual grinding. In a second phase, a reduction of diameter is carried out in an extreme region (2), in order to proceed, in a third phase, to an external pre-grinding (3), the fourth phase consisting in an internal machining of the extreme region (2) with a total concentricity. In the fifth phase, an inductive tempering is effected, and continuously, in a sixth phase, an external grinding is performed in order to obtain the desired external diameter, the seventh phase consisting in an internal grinding on the internal diameter of the area (2), and finally the eighth phase consists in a frontal facing (6), thereby obtaining an expulsion tubular (1) for moulds, in general. Optionally, a swaged head may be obtained at the posterior extremity of the tubular (1).</p> |