| 摘要 |
PROBLEM TO BE SOLVED: To arrange that attaching and detaching works of an insert tip to water passage fitting are facilitated, and that heat removal reliability and stability of the tip are promoted.SOLUTION: A plasma torch includes the insert tip 5, having a nozzle 51 at the center of the tip to eject plasma and having a male screw 53 at the rear end cylindrical part; the water-passage fitting 6, which has an inner hole 61 in the center, on its outside there is a cooling water passage and in which there is a female screw hole 68 on the tip part of the inner hole 61 into which a male screw 53 of the tip 5 is screwed; an electrode rod 8, which advances into the inner hole 61 and the tip of which opposes to the nozzle 51; a stone 9 that is in the tip 5 and supports the electrode rod 8 at the center axis position of the nozzle; a torch body 1, having a housing space to receive the water-passage fitting 6 from its rear-end side; and an inhibiting means 65, 11/66, 12 for inhibiting the rotation of the water-passage fitting 6 in the torch body. The female screw 53 is tilted at an angle of 10° or more and 30° or less on the front side of the cross-section perpendicular to the screw axis on the valley bottom side, at an angle of 20° or more and 35° or less on the rear side, and at an angle of 20° or more and 45° or less on the peak side with respect to the face in parallel with the screw axis. |
