An end product and system for connecting large aluminum tubular pipe segments into an Isolated Phase Bus comprising reducing the diameter (or increasing the same) of one end of a tubular segment and sliding it into (or over) the untreated end of an adjacent pipe or tubular segment, followed by a tubular and circumferential welding of the same. The outside or inside circumference of the connected segments are uniform from distal to proximal end of the overall length of the connected tubular segments. A structural integral, axially aligned, simplified set of connectable tubular segments allows for a grounded connection between power generators and step transformers. Preferably, the overall diameter change of the necked down flange (or outwardly flared flange) of one tubular segment is less than or only slightly greater than twice the material wall thickness of the tubular segment's initial pre-rolled flat aluminum sheet material.