| 摘要 |
Wiper plugs or other shapes are made from shape memory foam in a size large enough to wipe or clean a tubular of a predetermined size. The plug or other shape is then reformed to a smaller dimension above its transition temperature and allowed to cool while holding that shape. The smaller shape allows delivery through a running string that is smaller than the tubular string to be wiped. Preferably before reaching the string to be wiped, the trigger is applied to get the wiper or other shape above its transition temperature where it then reverts to the prior larger dimension for effective wiping of the string that it will next pass through. The trigger can be well fluid temperature or composition, applied heat from the tubular, generated heat within the wiper or other shape, or heat released from agents introduced into the well acting alone or in conjunction with well fluids. |
