| 摘要 |
The present invention relates to a wiper apparatus (1) for cleaning the inside of a drill string of drilling mud or other well fluids during drilling operations, wherein the apparatus (1) is made to float on a liquid surface of the drilling mud in the drill string (20) or be suspended from a landing seat (10), wherein the landing seat is arranged in a landing sub (21), wherein the apparatus (1) comprises a landing member (2), at least one buoyancy body (3), at least one centering element (4), and at least one wiper member (5, 6, 7). The wiper apparatus (1) comprises a spacer (9) between an upper (30) and lower (31) portion of the apparatus (1), wherein the spacer (9) has such a length that the buoyancy body (3) and the centering element (4) will not be located in the landing sub or tool joint when the wiper apparatus (1) is suspended from or rests against the landing seat, the buoyancy body (3) and the centering element (4) being arranged in a lower portion (31) of the apparatus (1) and the landing member (2) being arranged in an upper portion (30) of the apparatus (1). |
