Pipe tee forming machine - GIF

[Frank S]

Ok, so the real question is how do you fix that ball on the shaft? The rest I think I understand. Die to form the exterior is simple enough. That interior swage has to be the correct pipe I.D. but not necessarily a true sphere.

Mark

There would be predrilled or punched hole in the pipe the ball would be pushed in from one end then secured to the pull shaft by any of a number of means, it could be secured by rotating the pull shaft to make the connection possibly a 1/4 turn like bolt of a rifle locking a breach. or threaded. or the shaft could be hollow and split on the ends with a tapered draw rod inside making it an internal collet lock. but my vote would a the 1/4 turn or internal collet lock as being the most time expedient.