| 摘要 |
<p>A rock drilling rod is manufactured by placing free ends of first and second hollow rod components in abutment, and establishing relative rotation between the free ends to friction weld those free ends together. The first component comprises a thread and a clearance portion disposed adjacent the thread. The first component has a hot hardness value of at least about 170 HV1 at 600 DEG C. Prior to friction welding the components together, the thread, clearance portion and central passage of the first component are heat treated against corrosion fatigue. Then, the thread is high frequency hardened to a depth at least as great as the heat treated layer. Following the welding, the weld is cooled while keeping a core hardness of the respective portions of the first and second components disposed immediately adjacent the weld no lower than 390 HV1.</p> |
