steam radiator: knock apart

Maybe the sections are joined with screw nipples instead of push nipples?

MARK,

Thanks for help,

Could you describe how I would know the difference? What is a screw nipple or a push nipple.

Thanks, Frank

Frank,

I think they're just being stubborn. Use more muscle.

I may not be helping at all. I'm really taking a shot in the dark on this one. Cast iron boiler sections are put together in way similar to cast iron radiators. Most have push nipples ( short sections of pipe tapered on each end) between the sections. The tension rods pull the sections up tight and the taper makes a seal. But sometimes they have screw nipples between the sections. The holes between the sections are tapped and a nipple that has right hand thread on one end and left hand thread on the other end joins the sections. I don't know if radiators were ever made that way. If they were, the screw nipples would be accessible from the plugs on the end sections, and unscrewed with a special wrench.