Abstract: An adjustable clamp for welding together pipes, the adjustable clamp having a first axis perpendicular to the pipes and a second axis parallel to the pipes. The adjustable clamp includes four clamp corners, four transverse bolts, two parallel bolts, two threaded inserts, and four spaces. Each clamp corner includes a first transverse aperture, a second transverse aperture, and a third parallel aperture. The first and second apertures are transverse relative to the first axis and the third aperture is parallel relative to the first axis. Each transverse bolt is securable within the first and second transverse apertures of the four clamp corners. Each parallel bolt is securable within the third apertures of the four clamp corners. Each threaded insert is placeable within the third apertures of the four clamp corners and each threaded insert is mated with a respective parallel bolt. Each spacer surrounds a portion of each transverse bolt.

Abstract: A safety tether is provided for securing a heavy work tool. The safety tether includes one or more springs that serve to carry some of the weight of the work tool. A safety chain is provided in parallel connection with the springs. The length of the chain is less than the extended length of a spring at its maximum rated load, thus precluding extension of the springs to that link, greatly reducing any likelihood that the springs will break. In the event of spring breakage, the chain serves as a safety chain, stopping the tool from falling.

Abstract: A system is disclosed to use a first rotary milling head to break or cut the bond of a heat transfer fin base to a boiler tube, thereby removing the heat transfer fins from the boiler tube, and a second rotary milling head to bevel the exposed end of the boiler tube, thereby facilitating the more efficient repair of the boiler tube.