| 摘要 |
PROBLEM TO BE SOLVED: To provide a pipe washing pig superior in washability, without causing damage by water pressure and a pipe diameter change, even if density of a pig body is reduced, while smoothly passing without increasing launcher pressure.SOLUTION: A coating film composed of silicon rubber is provided on an outer peripheral surface of the pig body composed of flexible polyurethane foam in which foam density is less than 20 kg/mand 40% compressive hardness is 110 N/314 cmor less, and hardness measured by an ASKER rubber hardness meter C type is 0-1. At this time, the 40% compressive hardness of the pig body before providing the coating film and a pig after providing the coating film, is desirably the same. |
