Disconnecting a lead and oakum seal on a cast iron drain pipe

Cast iron drain / waste pipes they are most often joined with a lead and Oakum seal. Oakum is a hemp material coated in tar.  It is placed into the joint to seal it.  Oakum expands when it gets wet to seal the joint. The Oakum is held in place and the pipe joint is given some strength by casting a bead of lead around the pipe inside the hub socket. In this picture the cast iron pipe hub is on the left.

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This is how the pipe joint is put together originally – Pouring Lead Joint Horizontal