| 摘要 |
<p>An apparatus for cleaning the surface of a bore, for example an oil pipeline, which comprises a brush (12) extending along the periphery of a coil spring (11) so as to clean the surface of a bore as the apparatus moves along inside the bore, the brush being moveable inwardly and outwardly relative to the spring (11) to cater for bores of different sizes by twisting the spring and thereby varying its diameter. The brush (12) is moveable inwardly and outwardly relative to the spring (11) by inflatable or other means. Twisting of the spring (11) may be manual or by power-operated means. The ends of the spring (11) are attached to two end assembles (13, 14) which are connected respectively to two components forming a support extending through the spring, the components having cooperating screw threads permitting relative turning of the components for twisting of the spring (11).</p> |
