This invention relates to methods and materials for slip ring grinding of a generator rotor, without the need of dismounting the slip ring from the rotor of the generator, and allowing the grinding process to be performed whilst the generator is on full-load operation. As such the methods and materials of the present invention differs from current solution. Whilst allowing on-line grinding of the slip ring, the current solutions require low-speed rotations and accordingly operational shutdown of the generator. Allowing on-load grinding, the present invention greatly shortens the downtime of the generator and to perform maintenance on the slip ring beyond the provided standard maintenance schedule.

A pipe coating material removal apparatus, comprising a support frame, a subframe, and one or more coating material removal members. The subframe is supported by the support frame and is configured to rotate relative to the support frame at least partially around a subframe rotation axis. The subframe rotation axis is configured to be substantially coaxial with a longitudinal axis of a pipe to which the apparatus may be applied in use. The, or each, coating material removal member is rotatably mounted to the subframe to remove part of an exterior coating of a pipe. The apparatus is configured such that the one or more coating material removal members enable the removal of pipe coating material at orientations substantially parallel to, and inclined with respect to, the longitudinal axis of the pipe.

Embodiments of the present invention relate to roll polishers that may be utilized with rollers in rolling stands that have restrictive space requirements. The roll polisher of the present invention comprises a tube with pivot actuators used to engage and disengage a rolling pad on the surface of a roller. Transverse actuators may be located at least partially within the tube, or in other embodiments located outside of the tube, and used to move the tube, and thus, the rolling pad, transversely back and forth across the surface of the roller. The roll polisher may operate apply a force to the pad engaging the rolling surface to remove defects and smooth the surface of the polisher.

A pipeline pig for wetting the top inner surface of a pipeline comprising a pig body, one or more circular brushes attached to the pig body, and means for rotating the one or more circular brushes as the pig moves through the pipeline.

A device used for cutting a pipe from an inside. The device has a spindle arranged to be rotated. The device further has protrusions fastened to the spindle and arranged to position the device or a part of the device inside the pipe. The protrusions have at least one blade arranged to machine material off the inner surface of the pipe to cut the pipe while the spindle is being rotated.