CASING SCRAPER

摘要

A casing scraper comprises a plurality of blade modules (5,6,7) mounted on a mandrel (2). The blade modules (5,6,7) are identical to each other and have castellated ends which are engaged with the couplers (16,18) to prevent relative rotatio n between the modules. By manipulation of a thread protector (10) the modules can be operated in a configuration in which they are free to rotate relative to the mandrel or in a configuration in which they are rotationally fast with the mandrel. Each module comprises a housing in which a plurality of scraper blades are mounted. The scraper blades include shoulders which prevent the blades passing completely through mounting windows provided in the housing and are biased radially outwardly relative to the housing by compression springs.