| 摘要 |
There is disclosed an improved expandable centraliser ( 20;120;220;320 ), which may optionally also be adjustable, and a related downhole assembly and a method of completing a well. Previous art has suffered from a number of problems and essentially attempted to mitigate the effect of pipe expansion, i.e. using tension caused in the centraliser body. The centraliser ( 20;120;220;320 ) of the invention uses the expansion of the tubing to cause compressive forces, which are exerted over known distances to energise blades of the centraliser by using relative motion caused by said expansion. The expandable centraliser ( 20;120;220;320 ) comprises at least one first member ( 30;130;230;330 ), and at least one second member ( 35;135;235;335 ), wherein, in use, relative circumferential motion of the at least one first and second members ( 30,35;130,135;230,235;330,335 ) causes radial motion of at least one portion ( 40;140;240;340 ) of the expandable centraliser ( 20;120;220;320 ).
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