WHIPSTOCK

摘要

A whipstock (1) comprises a concave (2) which comprises a tapered support member (3) which accommodates a plurality of spacers (7). The spacers (7) can be moved from an inoperative position to an operative position in which they project outwardly from the tapered support member (3) to support the tapered support member (3). The spacers (7) are shaped and disposed so that when they are moved to project outwardly from the support member (3) they project by different distances from the support member (3).