A COUNTER ROTATING PIN AND SHOULDER TOOL ARRANGEMENT FOR FRICTION STIR WELD SYSTEM.

摘要

The present invention relates to a counter rotating pin and shoulder tool arrangement for friction stir weld system involving a self powered variable speed counter rotating shoulder set-up. Importantly, the system and method for friction stir welding enable shoulder rotation in opposite direction to the pin with different speeds. No additional power supply has been provided for the variation of speed of the shoulder. The pin and shoulder are powered from a single source i.e. spindle of the machine, involving selective geared combination among a primary shaft, an intermediate shaft and a driven shaft. This counter rotation facility helps to minimize the thermal imbalance between advancing side and retreating side which helps to improve the weld strength. The weld strength and corrosion resistance of weld regions of FSW is improved. The speed of the shoulder can be controlled for welding of low melting point materials such as aluminium, magnesium, HDPE etc.