| 摘要 |
FIELD: oil and gas production. ^ SUBSTANCE: drilling three-roller bit comprises support brackets with inclined pivot shafts and rolling cutters mounted thereon by a retaining bearing with their base and inverse cones reinforced by hard-alloy teeth and rotating rock cutting elements respectively. Each rock cutting element on the inverse cone of the rolling cutter is provided with a stepped flushing hole wherein there is a reciprocal clamp rigidly connected to the body of the rolling cutter. Within a cavity of the step of greater diametre of the flushing hole of each rock cutting element, there is a diamond-set hard metal alloy plate. This plate is rigidly connected with the rock cutting element. The cavities between the rock cutting element and the clamp on one side and walls of the hole on the other side are filled with a hydrolayer and sealing. ^ EFFECT: longer operational life of the rock cutting elements and the whole boring cutter, higher drilling feed range and speed. ^ 3 cl, 3 dwg |
