TPT July 2008

T echnology U pdate

Profile welding system with fully integrated sensor technology

on the welded component. In contrast to conventional TIG welding, non-contact laser welding achieves higher process speeds, and the weld seams generated are capable of withstanding high stress levels without tearing. The Profile Welding System consists of a beam guidance and sensor system together with PC-controlled linear axes. All laser system functions, such as control of process gases, monitoring of the optical safety circuit and overall monitoring of the laser system and its associated cooling system, are handled by the integrated PLC control system. A bundle type tube feeder, integrated with the machine, automatically loads tubes up to 6m in length, and up to 75mm in diameter. In the first station, the tube is cut-off and the consequent slug/blank is then indexed from station to station in order to machine the entire external and internal diameter, and also any radial operations, allowing the production of complex parts. During machining the parts may be clamped with jaws, collets or high precision self- centring chucks that are positioned on the perimeter of an indexing turret of between 4 and 20 stations. The part is completely machined internally and externally with numerous tools working simultaneously from more than one direction (opposing, transversal and inclined). At any station the semi-machined parts can be rotated, allowing machining of high precision parts as well as very long parts. The machines are suitable for the complete

The Macro Group of Rofin, Germany, has launched a new Profile Welding System designed and configured to weld tubes and profiles using fully integrated sensor technology. This technology is designed to detect the weld gap and enable seam tracking. The laser welding process for joining tube and profiles enables narrow seams with fine grain structure to be produced together with a minimum of heat affected zone. The controlled and predictable nature of the laser welding process also means that in the majority of cases, no further heat treatment or processing is required

 Rofin’s Profile Welding System

The sensors used for weld seam position recognition and seam tracking can detect the slightest discrepancies in the seam position. This adaptive system ensures that the laser beam always follows the seam, providing high process reliability and consistency. The high-speed precision linear drives used by the Profile Welding System provide positional accuracies of 20µm at production speeds of up to 60m/min. A field proven beam delivery system on the Profile Welding System provides safe operation under tough industrial conditions. The system is not sensitive to oil, dirt, dust or damp and is also virtually maintenance free, providing high uptimes and reliability. A display unit mounted on a moveable support arm provides ease of use for operators. This allows centralised monitoring and optimisation of the laser parameters and functions together with seam tracking on the workpiece. Designed with modular construction in mind, the system can be easily configured to suit specific requirements. For example, the beam guidance system can be supplied with either a beam switch unit or a beam splitter unit, the latter enabling simultaneous operation on several systems or alternatively at multiple welding points. A number of options are also available for the Profile Welding System that can be used to further customise its configuration for a specific application. These include process gas jet geometries configured for the application; a 30° rotating weld head, enabling ‘drag welding’ for higher welding speeds; and process data monitoring and storage for quality purposes. The Profile Welding System is based upon the successful range of Rofin CO 2 slab lasers. With up to 8kW of output power available and excellent beam quality

Multi-station production of complex parts Trans-Bar machines from Buffoli Transfer SpA, Italy, are multi-spindle CNC transfer machines fed with non-rotating bars or tubes of any profile and material.

 Buffoli machines can be used to machine turned parts without costly secondary operations

machining of turned parts without costly secondary operations. While the machines are quickly re-tooled, like a two-spindle CNC lathe, they offer higher productivity than a multi-spindle screw machine. Thay also allow the complete processing of parts that cannot be completely machined on lathes. Average setup times range from 30 to 90 minutes, and a wide range of quick- change accessories are available, allowing production batches of a few thousand parts. Machines with tube sizes up to 45mm are also produced in double production versions, and can reach four times the productivity of a multi-spindle lathe (up to 12,000 parts/hr). Buffoli Transfer SpA – Italy Fax : +39 030 201556 • Email : info@buffoli.it • Website : www.buffoli.it

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J uly 2008

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