Friction stir welding, a solid state joining technique, is widely being used for joining Al alloys for aerospace, marine automotive and many other applications of commercial importance. FSW trials were carried out using a drilling machine on Al 6063 alloy. The tool rotational speeds 485, 710, 910, 1120 and 1400 rpm with a traverse speed 4 mm/min were applied. The Mechanical properties of welded joints were investigated using different mechanical tests including destructive test (tensile test, hardness and microstructure). Based on the stir welding experiments conducted in this The resultant microstructure was characterized using optical microscopy This paper presents the optimization of friction stir welding for pipe and also highlights the influence of microstructure and mechanical properties of FSW 6063 Al alloy.