View Full Version : Cast Iron to PVC
topcat6
Jul 31, 2009, 10:21 AM
What is the best method for a hoizontal replacemant? Should I just snap cut the cast and use a Fernco banded conector, remove the lead and okum joint in the hub and use a hub connector, or install a PVC cast to pvc hub connector and use okum and plastic shield in the hub? What is the BEST way for this?:confused:
massplumber2008
Jul 31, 2009, 01:22 PM
Hi Topcat...
Best bet here is to cut the cast iron pipe in two places using a sawzall and bimetal cutting blades and then use two shielded clamps (see image) to connect pipe in between. If, say, you cut 12.5" out of the cast iron you will cut the PVC pipe about 12" long and install that in between the clamps... the two clamps each have RIBS that will fill in the 1/2" void. Here, you would slide the clamps onto the pipes and then FLIP the rubber sleeves back on themselves and then drop the pipe in between the sleeves and FLIP the sleeves back onto the pipe. Slide the clamps and all set, etc.
If replacing cast iron with PVC then you will need cast iron to PVC shielded clamps.
Do NOT use the all rubber clamps with 2 SS bands... these are really just for underground applications.
Finally, when cutting cast iron pipe be sure to support the pipe and/or vertical load before cutting into the pipes. I cannot emphasize that enough!! Let us know if you need info. on this... ;)
Let us know if you have more questions...
MARK
topcat6
Aug 1, 2009, 02:32 PM
Thank you for a 1st rate instruction with diagrams included, I understand the easy method of using a banded clamp and have conquered that job previously. What is the best method of joining these two materials that will outlast the other and hold stronger? Hub conector, banded clamp, pvc to cast hub with okum and plastic seal?
massplumber2008
Aug 1, 2009, 03:55 PM
Hi Topcat:
In this case, the BEST method is ABSOLUTELY to use the banded shielded clamp. In your case a cast iron x PVC shielded clamp (see 1st image) is the way to go. Here, these shielded clamps are actually transition clamps that make up for the size differences between the two different pipe types (pvc/cast iron). These are used commercially and residentially for all similar applications.
DO NOT use the all rubber type of coupling with 2 SS clamps (see 2nd image). These are not correct for your application.
MARK