Page 188 of 561
TINBRO-341
Unitor TINBRO-341 is a tin-bronze elec Cunifer trode for DC welding, positive polarity. Small parts should be brazed with AGAreas of application include joining of 60 and AG-60/45 Flux-252 PF. Larger dimensions should be TIG welded brass and tin-bronze as well as joinwith Icuni 30 329. ing these to steel and cast iron. Clean the welding area thoroughly to remove any oily deposits, oxidation, etc. Machine or grind off fatigued material. When making joints, a 3 mm gap should be used. When material thickness is more that 4 mm, make an 80° welding groove with V or X profile. It is recommended that larger copper alloy parts should be pre-heated to 300–500°C. This will facilitate welding, and welding current can be reduced. Use a short arc and hold the electrode almost at right angles to the work. On parts requiring thin surfacing, weave the electrode from side to side, covering an area of up to three times the electrode diameter.
3.01
Parts not be overheated, or where minimum fusion with the base material is required, welding should be carried out at 80–110 Amps.
The electrodes must be stored in a dry place and must be handled carefully to avoid damage of the coating. TINBRO-341 is not recommended for welding Yorcalbro (aluminium-brass) or Cunifer (copper-nickel, cupro-nickel). For welding these materials, the following processes should be used:
Yorcalbro
For dimensions up to approx. 4", braze with AG-60 and Albro Flux 263 PF. For larger dimensions, use TIG welding with Ialbro 237 MF.
187