Plumbing – Connecting PVC to a 4.5 inch ID cast iron hub

Yes, quite simple.

1. use a Scotchbrite pad to shine up the copper tube so the ferrule ring has a clean, gouge free seating area
2. slide the nut on
3. slide the ferrule ring on
4. push the copper tube into the fitting till it seats (fittings I've used have an internal stop at about 1/4" from ferrule seating area, double-check that the fitting is designed this way)
5. push the ferrule ring into place against the fitting
6. thread the nut on by hand (make sure the tube doesn't back out of the fitting and till nut is hand tight)
7. tighten the nut just till the fitting is leak-free (about 1/2 turn from hand tight)

No plumber's goop, no teflon tape on assembly, the seal is formed by compressing the ferrule ring.

Where most people go wrong is to over-tighten the nut for the ferrule ring. The ferrule ring is trapped between two conical surfaces (nut and fitting) that force the ring to bite into the soft copper which both seals and forms a mechanical connection to keep the tube from backing out. Over-tightening causes the ring to dent the tubing, causing leaks and the inability to disassemble and reassemble the fitting as all the give is taken out of the ferrule ring and it cannot compress any more to seal effectively on the next reassembly.

Re-leading the joint isn't too hard. You will need a slug of lead, a ladle, yarning iron, packing iron, caulking irons, oakum, and torch. The process goes like this:

• Safety first! Wear thick leather gloves and avoid eating lead particles.
• Clean the old lead out
• Using a yarning iron, pack the oakum around the pipe. Repeat this operation until the hub is packed to about 1” from its top. Pack the oakum with a hammer and packing iron to make a bed for the molten lead.
• Using the plumber’s ladle, carefully pour the molten lead into the joint, as shown in Figure 30. Dip enough lead to fill the joint in one pouring. Allow a minute or two for the molten lead to harden and change incolor from royal blue to a dull grey. Usually, one pound of lead is melted for each inch of pipe size.
• Caulk the joint first using the outside caulking iron and then the inside caulk ing iron. The first four blows should be struck 90 degrees apart around the joint to set the pipe. Drive the lead down on the oakum and into contact with the spigot surface on one edge and the inner surface of the hub on the other. Use firm but light hammer blows.

The process isn't really hard at all for vertical pipe, but does require some specialized tools. If you have several of these joints in your house, it might be worth the investment!

Yarning irons:

Caulking Irons:

Inside/Outside Caulking Irons:

Ladle:

Horzontal Pour: