Table 3.

Summary of results obtained by the visual inspection.

			Traverse Speed (cm/min)
			20			30
	Rotation Speed (RPM)	500	R1T1	Weld Pitch	R2T1	R1T4	Weld Pitch	R2T4
Internal void			absent	0.40	absent	absent	0.60	absent
Surface defect			absent		absent	absent		absent
Lack of penetration			absent		absent	absent		absent
Excessive flash			absent		absent	absent		absent
		700	R1T3	Weld Pitch	R2T3	R1T2	Weld Pitch	R2T2
Internal void			absent	0.29	present Type: “tunnel”	present Type: “tunnel”	0.43	present Type: “tunnel”
Surface defect			absent		present	present probably formed during the transitional phase		present probably formed during the transitional phase
Lack of penetration			absent		absent	absent		absent
Excessive flash			absent		present on Advancing Side	present on both sides of the joint		present formed more on Advancing Side