| 摘要 |
In the hard metal plate (1) a staged hole (11) is made, the greatest section in dia. of which extends through an essential part of the hard metal plate thickness. Its section with a smaller dia. has a greater dia. than the precision hole (2). In the larger dia. section of the staged hole a platelet (21) of drillable different material is inserted. In the platelet, the precision hole is made within the contour of the smaller dia. section. The platelet is made of a drillable metal or plastics or a plastics-bound composite material. It is adhered in the staged hole, soldered, welded or metallurgically connected with the hard metal plate by another method. |
