Cutting and welding pipes from the inner part of a tube is an application well fitted to the laser technology. We have realized an optical head, which has to be inserted inside a 30-mm diameter internal tube with a 400-mm length, in order to cut and assemble tubes of 30 and 100 mm diameter.
A 3.5 kW diode pumped laser (HPDPL), with a 400 microns fiber is used for this application. Optical fiber and gas connecting part, motorization, on line control are located outside of the tube. A dedicated welding and cutting head is realized for each diameter to be cut and welded. This specialized tool is adaptable to the common part assuming beam transportation, connection and on line control. Particular attention is brought to the 100-mm cutting diameter for which a retractable nozzle has to be realized. On line monitoring with CCD video camera gives information about the process quality as well as for cutting or welding process.