One solution to this problem is the use of Argweld® Weld Backing Tape™ from Huntingdon Fusion Techniques HFT®. This high temperature resistant glass fibre tape supports weld roots and eliminates the creation of slag, while removing contact with air to dramatically reduce the amount of oxidation.
Luke Keane, Technical Sales Manager for HFT® said: “Weld Backing Tape™ is a common material used for manual and automatic welding to achieve higher welding speeds and dramatically reduce the amount of post weld cleaning.
The HFT® glass fibre Weld Backing Tape™ has no true melting point so it works satisfactorily with TIG or MIG welding (GTAW or GMAW) where temperatures can reach up to 6,000ºC. This overcomes the concerns associated with ceramic fibre versions that have a melting point of 1,800ºC,
HFT® manufactures four grades of Weld Backing Tape™ for use up to 80, 160, 240 or 600 Amps.
Each tape comprises a 3" (75mm) wide aluminium adhesive tape, in the centre of which is a 1" (25mm) wide band of woven glass fibre. The glass fibre matting has differing thicknesses to match the welding current in use.
Once the tape is positioned with the glass fibre matting under the centre of the weld joint, the welders can start their arc. The welding torch argon flow has plenty of space to move between the pores of the matting, which allows the welding arc to stabilise and start forming the weld root.