Abstract: A well cleaning attachment useful as a part of a collection of tools sent down a well bore on a tubing string includes a tubular mandrel provided with a plurality of longitudinal slots in which corresponding knife carriers are inserted. Each carrier is bedded on a leaf spring for radial motion within the slot and each is provided with a spring biased blade extending pivotally to the exterior. Two collars then fix the carriers within the slots, the same collars also engaging the periphery of the mandrel.

Abstract: A water pressure cleaning assembly useful in cleaning out the perforations in a well casing includes a mandrel structure defined by an upper cylindrical segment and a lower conical segment. An upper and lower annular seal is movable respectively along the upper and lower segments to allow relative motion of the mandrel structure within the annuli thereof. This lateral motion then allows the passage of the assembly across irregularities in the casing.

Abstract: A well casing cleaning assembly includes a cylindrical mandrel in which a spiral arrangement of transverse drillings is formed each of the drillings receiving a coiled spring intermediate the bases of exteriorly projecting knife blades. A set of arcuate plate segments, provided with vertical slots at each of the drillings, is then secured to the exterior of the mandrel compressing the springs and exposing the blade ends. An upper and lower packing on the mandrel then confines pressurized cleaning fluid.

Abstract: A grip device for mounting along a horizontal line, such as a rope or cable, to prevent a load from falling when one end of the line is no longer supported in its horizontal position. The device consists of a shell in which is mounted by means of a pin, a clamping wedge arranged such that when the handle of the wedge is moved in either direction, the wedge becomes clamped against the rope or cable to prevent movement of the rope through the device, and therefore prevent falling of a person attached to the device by means of an approved belt, harness or lanyard.

Abstract: A safety device for securing a scaffold to the side of a building in order to prevent movement thereof is disclosed. Such securing of the scaffold is achieved by placing a lanyard, preferably an adjustable lanyard, around the rope supporting the scaffold and securing the lanyard to a stud on the side of a building through the use of a yoke.