| 摘要 |
PURPOSE:To strip and remove scale by inserting an annular washer between the head part of a scraping pin and a solid cylindrical body 1 and specifying the size of the scraping pin and the annular washer to a specified size. CONSTITUTION:The scraping pin 2 implanted to the solid cylindrical body 1 is formed of a hard material softer than a pipe which is an object to be cleaned. The pin 2 is inserted with a toric washer 6 between the body 1 and the head part 5. The sizes of the pin 2 and the washer have the relations expressed by the equations (1)-(6). (In the equations, d1: the outside diameter of a base shaft 3, d2: the outside diameter of an arrowhead part 4, d3: the diagonal line length of a square collar 5, a: the projecting length of the head part 5, D2: the inside diameter of the washer 6, b: the difference between the inside and outside diameters of the washer 6). The base shaft 3 of the pin 2 is pressed to the central aperture edge of the washer 6 and the cleaning efficiency is improved particularly when the above-mentioned sizes are determined at the relation expressed by the equation(6). |
