| 摘要 |
PROBLEM TO BE SOLVED: To excellently perform blast processing on a column outer peripheral surface by moving a device main body in the lengthwise direction of a column while maintaining an attracting condition to the column outer peripheral surface after its dead weight is supported by attraction force to the column outer peripheral surface and driving force to roll wheel members and auxiliary wheels on the column outer peripheral surface. SOLUTION: Auxiliary wheels 21A and 21B are held in a vertical posture to a tangent on a column outer peripheral surface 1a, and a blast device 10 smoothly rolls on the column outer peripheral surface 1a together with wheels 11A and 11B when moving in the vertical direction along a column 1. The blast device 10 is attracted to the column outer peripheral surface 1a by reducing internal pressure of a space part 20 through a pressure reducing passage 15. In a condition where the blast device 10 is attracted to the column outer peripheral surface 1a, a grinding/polishing/cleaning material is projected toward the column outer peripheral surface 1a in the space part 20 from a grinding/ polishing/cleaning material nozzle 6. |
