A pipe is only as strong as its weakest link. However, an effective backing ring can support and enhance the o-ring, flange adapter, or other fitting it’s paired with. Our pipe fitting design is focused on the big picture: how each piece aligns, how they rely on and support each other to create a reliable, resilient infrastructure. That’s how we got into the custom fittings business. No matter what the ring is backing up, we can custom select the size, shape, and material to get the job done.
Backing Ring Materials
This hearty alloy is rich in graphite, making it more resistant to pressure and impact than other grades of cast iron. In the casting process, the graphite forms into spherical nodules, creating a crack-resistant structure.
Ductile iron is the most affordable and most machinable material we suggest for backing rings. We coat each iron fitting in either epoxy or primer to shield against corrosion, though it’s still more vulnerable to moisture than steel.
It is generally more friction-resistance than steel due to the high graphite content, though this varies depending on the quality of the friction. Consult an expert to determine which material is best for your situation.
The second-most affordable backing ring option is steel protected from corrosion with a thick zinc coating. If the coating wears away, it still rusts slower than iron. However, galvanized steel doesn’t offer the same level of corrosion resistance as stainless steel. In low-moisture, low-pressure settings, galvanized steel is the best fit.
The most corrosion-resistant iron alloy is formed by introducing chromium to molten steel. It’s well suited for transporting liquids, even salt water and certain acid contents. However, chlorinated water is the enemy of stainless steel and leads to rust.
This in-demand material requires the greatest cost investment but lasts longer in humid conditions.
Pro tip: If two stainless steel fittings are held together under friction, they will eventually weld into one piece. This is something to bear in mind in the long term, as it can complicate repairs.
Don’t see your material on the list? We fabricate and mold new fittings every day. We would love to accept your custom order. Get a quote on your pipe fittings order.