| 摘要 |
A method for testing durability of blades for mandrel tools, especially drills, applied in such a way that a tool is secured in grips and made subject to a simultaneous action of a torsional force and a compressive force. The method is distinctive in that the torsional force exerted is preferably one and a half time stronger than that occurring during cutting and the compressive force exerted is preferably one and a half time stronger than that occurring during cutting; both forces build up for 30 seconds at a rate no faster than 1 kg per second until the final value is reached; in conditions so set the tool is held for at least 30 seconds and then, the forces still being exerted, an angle of torsion is measured (γ degrees) within the limits of material elasticity and durability determined according to the formula<IMAGE>
|
