| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase the quantity of soil to be removed by devising the shape of a seal cup 3 for cleaning in a cleaning pig to improve the cleaning and wiping-out ability. SOLUTION: One or a plurality of grooves 32 formed ring-like in the peripheral direction of the seal cup and having a rectangular cross section are arranged on the outside surface of the seal cup 3 attached to the cleaning pig for cleaning a conduit and a strippable coating layer 33 is formed on the inside surface of the groove 32.</p> |
