Abstract: An apparatus comprises a body having V-shaped two-arm levers mounted thereon. Around the periphery of the body there are mounted cutting tool holders pivoted each to one arm of each of the levers. Secured to the body are drives for turning the levers and each connected with the other arm of each of the levers. On the front and rear ends of the cutting tool holders there are mounted rollers in contact with the inside surface of the pipe. Rigidly attached to the cutting tool holders are cutting tools.

Abstract: A nonconsumable electrode comprises a hollow cylindrical body, a hollow detachable tip made in the form of a body of revolution coaxial with the hollow cylindrical body, a solenoid for generating a magnetic field, and a partition. The tip is secured to one of the ends of the body and has lateral cylindrical non-arcing portion and a convex arcing end portion. The lower end of the solenoid is disposed in the tip cavity defined by the cylindrical non-arcing portion of the tip. The partition is coaxially mounted in the cavity of the body and of the tip so that between said partition and the walls of the body and of the tip there is formed a passageway for the flow of a coolant.

Abstract: A tank furnace comprises a first container containing a molten flux and connected with a hoisting mechanism, and a second container containing a molten coating metal. The second container is stationary mounted so as to be placed inside the first container when in its upper position. The mechanism for advancing articles into the coating zone is connected with a device for controlling the depth of immersion of the articles being coated. The first container is fitted with electrodes.