| 摘要 |
This invention provides a scraper cup for use with a pipeline pig, the scraper cup being generally dished or cotyloid in shape, and having generally a thicker wall to one side of its geometric centre than to the other side of its geometric centre. Thus, the centre of gravity of the scraper cup is displaced from its geometric centre, and the effect of this on the pipeline pig is to impart to the latter a tendency to seek a given horizontal orientation, in which the centre of gravity of the scraper cup is positioned directly below its geometric centre. |
