MU IV — Open Orbital Welding Head for Tubes Ø8–195 mm

Technical specifications

Specifications are taken from the manufacturer’s technical documentation. Updated 11/06/2026.

Description

The torch with a ceramic nozzle and a gas lens rotates around the pipe through a planetary drive, and a motor with an angular gearbox reduces the axial size. The welding speed is held in a closed loop, an encoder runs the program by the electrode position, and a mechanical sensor maintains a constant distance to the workpiece. The clamp comes in two systems. C shells are matched to a specific diameter and have water cooling for preheated tubes, while the P chuck adjusts over the whole range. The wire is fed by a built-in mechanism with a 1.5 kg spool or an external POLYFIL with a 15 kg spool, and the wire position is adjustable along two axes. In the AVC/OSC version the arc voltage and torch oscillation are motorized for multi-pass welds of medium and large thickness. According to users' experience, an operator makes 30 % more welds per day than by hand. It works with the sources P4 at 170 A, P6 at 300 A, the previously produced PS 164-2 and Polyfil mechanisms.

How to choose

The size is chosen by the diameter range. Clamp C covers 14–128 mm in five sizes (14/38, 30/58, 30/80, 50/115, 50/128), and clamp P covers 8/38, 14/38, 19/80, 25/115, 25/128 and 76/195. The AVC/OSC version is available as 14/38 (from 8 mm), 30/51, 30/64, 30/80 and 50/128. For diameters of 76–195 mm with hot wire there is a separate MU IV 195 HW. For frequent diameter changes clamp P is more convenient, and for series production clamp C. If the tubes are thin and ultra-high purity is needed, see the enclosed UHP heads.