Furse FS005 Silfos

• Self fluxing brazing compound used to make a permanent connection when joining copper conductors
• Used in substation earthing where space is restricted
• Silfos alloy of silver, phosphorous and copper
• Used to braze copper in air without the use of Flux

Joint Preparation

• The two conductors (copper tapes) to be jointed should overlap a distance at least equal to the width of the thinnest conductor. E.g. 50mm x 6mm to 25mm x 3mm the overlap should be at least 25mm.
• The mating faces of joints should be as flat as practicable, they should be wire brushed until the two surfaces are bright and slightly roughened. Emery paper or sand blasting does not provide a suitable surface.
• The preferred heat source is Oxy-acetylene, if unavailable Propane should be used.

Jointing Procedure

• The two tapes to be jointed should be clamped together with a suitable length of Silfos Foil between the mating faces.
• The joint is rapidly heated to approximately 700 °C at which time the foil should be seen to flow. It is not good practice to keep the alloy molten for long periods.
• Unsatisfactory joints should not be reheated; such joints should be re-made from scratch.

Joint Testing

• Completed joints should be checked visually for signs of a weakness around the perimeter of the joint.