Jack with two masts

A jack for raising a ring segment of a cylindrical structure on a foundation pad, comprising:

• (a) a pair of generally identical upright masts, each mast extending from a lower end to an upper end, each mast presenting a plurality of evenly spaced holes,
• (b) a mast base operable for receiving the lower ends of the masts and securing the lower ends of the masts to the foundation pad in a side by side spaced apart relationship,
• (c) a mast cap operable for receiving the upper ends of the masts and securing the upper ends of the masts in a side by side, spaced apart relationship,
• (d) a hydraulic ram having a lower end and an upper end, the hydraulic ram operable for movement between a retracted position and an extended position, when in the extended position, the distance between the lower end and the upper end of the hydraulic ram being greater by a stroke distance than the distance between the lower and upper ends of the hydraulic ram when in the retracted, the stroke distance being substantially less than the length of the masts,
• (e) a back strut operable for connecting between the mast cap and a support location which is spaced away from the mast base,
• (f) a bottom bracket which connects between the masts and which is adapted to be removably pinned to corresponding pairs of the evenly spaced holes of each mast, the bottom bracket operable to receive and support the lower end of the hydraulic ram such that the lower end of the hydraulic ram is positioned generally between the masts, the bottom bracket also operable for sliding vertically when the bottom bracket is not pinned to the masts,
• (g) a shuttle which connects between the masts and which is adapted to be removably pinned to corresponding pairs of the evenly spaced holes of each mast, the shuttle operable to receive the upper end of the hydraulic ram such that the upper end of the hydraulic ram is positioned generally between the masts, the shuttle also operable for sliding vertically when the shuttle is not pinned to the masts, the shuttle having features for connecting to a segment of a structure, the shuttle presenting a king pin,
• (c) an indexing bolt bracket which is connected to a ring segment of the cylindrical structure, the indexing bolt bracket having a slot suitable for receiving the king pin and the base pin, the slot including an upright portion, a lower slanted exit portion and an upper inclined portion having a slanted upper edge, the slot of the indexing bolt bracket arranged such that during a first lift of the shuttle, the king pin and the base pin are both initially received by the upright portion of the slot and such that, as the shuttle is raised, the king pin comes into contact with the slanted upper edge of the upper inclined portion of the slot as the ring segment is lifted off the foundation pad and as the base pin enters the slanted lower exit portion of the slot, and such that as the king pin further engages the slanted upper edge of the upper inclined portion of the slot and is further received by the upper inclined portion of the slot, the ring segment incrementally rotates in proportion to the lateral movement of the king pin within the upper inclined portion of the slot to an incrementally rotated position, the base pin exiting from the lower exit portion slot as the shuttle, the indexing bolt bracket and the ring segment continue to be lifted, and such that subsequent lift operations of the shuttle are conducted with the king pin being received by the upper end of the upper inclined portion of the slot as the ring segment is lifted in the incrementally rotated position
• whereby when the bottom bracket is secured to the masts and the shuttle is not pinned to the masts, a ring segment of structure connected to the shuttle can be raised by extending the hydraulic ram from the retracted position toward the extended position, and whereby, when the raised shuttle is pinned to the masts and the bottom bracket is unpinned, the bottom bracket can be lifted toward the shuttle by contracting the hydraulic ram toward the retracted position, and whereby, after pinning the lifted bottom bracket to the masts and unpinning the shuttle, the shuttle and the segment of structure attached to the shuttle may be raised again by again extending the hydraulic ram toward the extended position, and whereby these steps may be repeated until the shuttle has reached the top of the masts.