| 摘要 |
A hydraulic bolt tensioner for tensioning a threaded bolt (2) extending from a fixed component (4) comprises a cylinder (10) adapted to react against the component (4), a piston (12) slidably mounted in the cylinder (10) and having an axial bore (14) therein through which the bolt (2) extends, the piston (12) reacting against a reaction member (52) threaded on the bolt (2), and a source of hydraulic fluid (46). Defined within the cylinder (10) are a first chamber (36) the supply of fluid under pressure to which effects powered extension of the piston (12) within the cylinder (10), and a second chamber (34) the supply of fluid under pressure to which effects powered retraction of the piston (12) within the cylinder (10). |
