| 摘要 |
Method for the manufacture of wear bushes for a drilling device containing a frequency generator for detecting the position of the head, characterised : - in that at least one body (10) made of synthetic material is made up; - in that at least one end of the body (10) is fitted with a ring (12) made of steel having a high abrasion resistance, which projects in relation to the outer periphery (10a) of the body (10); - in that a material (15) is deposited at the periphery of the body (10), this material having a high abrasion resistance and being permeable to the position-detecting frequency, with a thickness compensating for the projection formed by the ring (12); and - in that the body (10) is fitted with means for connecting it with at least one part of a drilling head (1). <IMAGE>
|
