The present invention is directed to methods for repairing pipes or pipe junctions. The methods include providing a launcher device having a bladder and a liner impregnated with a material capable of curing and hardening. The bladder includes a first end, a closed second end, and an opening proximal the closed second end. A portion of the bladder is positioned within the launcher device, a rope or a line is connected to the liner, and the rope or line is threaded through the opening in the bladder. The rope or the line is pulled until the liner is at least partially within the bladder, and the rope or line is removed. The pipe is repaired by positioning the liner against the wall of a pipe, and allowing a material capable of curing and hardening to cure and harden. The methods allow for the rapid reuse of the bladder.

A method for repairing bucket which saves time in maintenance operations, wherein the bucket is cut by separating it into two parts, an upper part which is maintained and repaired, and an original bottom one, which is retired replacing it once the repairs of the top are completed with a new bottom part. Repairs are made at the top which has been maintained, and once said repairs are finished the top is welded to the new bottom. The original door is removed and replaced by a new door or a previously repaired one which is kept in Stock. Accessory parts and the new door are mounted and the corresponding tests are done to obtain a new reconditioned bucket.

The present invention is an improved method and assembly for repairing a pipe or the junction of two pipes, such as sewer pipes. The assembly includes a launcher device having a launcher device body, a launcher device opening disposed on the launcher device body, and a main bladder substantially surrounding the launcher device body. The main bladder includes an opening that substantially aligns with the launcher device opening. The assembly further includes an absorbent liner and a lateral bladder having a tubular lateral bladder body portion and a flange portion. The flange portion of the lateral bladder is attached to the exterior of the launcher device body. A method of using the assembly includes impregnating the liner with resinous material; inserting at least a portion of the liner into the lateral bladder; inflating the bladders; pressing the liner against the pipe; and allowing the resinous material to cure and harden.

A repair method is a repair method of a rotor including a rotor body extending in an axial direction about an axis and a plurality of impellers arranged in the axial direction and fixed to the rotor body, the repair method including: a step of performing welding on a repair area of the rotor body to fill a damaged portion with a welded portion; a step of performing heat treatment only on the repair area in the rotor after the welding is performed; and a step of scraping a part of the welded portion after the heat treatment is performed, to form a processing surface smoothly connected to an outer surface.