| 摘要 |
<p>A method of assembling sections of an earth boring bit for welding has features to assure precise bit geometry. The method includes a step of providing a hole in each bit section at the centerline of the 120 degree faces on the interiors of the sections. A triad is constructed for use in assembly and consists of three pins joined together on one end, each having an axis 120 degrees apart from the other axes of the pins. The triad is positioned in the holes in the 120 degree faces when the three sections of the bit are brought together. The shank ends of the sections have holes for receiving dowels located in the welding fixture. Once the sections are positioned and pinned against movement at the shank ends and at the triad, the sections are clamped, then welded.</p> |
