Dielectric Union

Dielectric Union Definition

Dielectric Union Definition

Dissimilar Metals Can Cause Problems in Plumbing

Galvanic Corrosion

Galvanic Corrosion on Water Heater

There’s a lot of plumbing around the house that normally different pipes to tap into each other; to set up a bar sink, for example, or possibly to include an additional outlet hose bib, even water heater connections fall into this category. Plumbing work frequently requires connecting one piece of metal into another. This is made possible with using the proper types of joints and unions. Understanding the correct parts and how to use them can really make the difference. When two different metals come in contact with each other, an electrolytic reaction begins, where water serves as the electrolyte. As a result the metals start to corrode. This unique process is called galvanic corrosion.

To stop this from occurring, a unique adapter is utilized to separate the two metals by using an elastomeric rubber gasket in between the dissimilar metals. This special fitting is called a dielectric union. When connecting copper pipe to galvanized iron pipeline for example, a dielectric union is installed to hold the 2 different metal pipelines together. However, there’s yet another alternative to a dielectric union– a brass nipple or a brass fitting which likewise certifies as a copper alloy fitting and complies by building codes too. So should you utilize a dielectric union or a brass fitting to link two different metal pipelines? Let’s see how they differ in their properties and performance.

So Just What is Dielectric Union?
A dielectric union is a special adapter or fitting utilized in the piping systems of various metals to isolate the connection of the dissimilar metals. For instance, when linking a copper pipeline to a galvanized iron pipe, a dielectric union is set up between the two to hold the two different metal pipelines together. An elastomeric rubber gasket seals the connection to prevent any water leak and a plastic composite material isolates the copper tube connection to hex nut on the dielectric union. Different metals begin to corrode when they can be found in contact with each other. The small quantity of acid on water sets off the electrolytic response between the two metals causing electrons from one metal to stream to the other. This ultimately results in galvanic corrosion. To stop this from taking place, a dielectric union is used to sign up with the two dissimilar metal pipes.

Brass Fitting

Example of a Brass Fitting

When to Use Brass Fittings
Brass fittings and nipples are also frequently used as a great alternative to dielectric unions for plumbing. When galvanized water is exposed to particular water qualities, rust is produced and to prevent that from corroding, fittings made of brass are often used. Both dielectric unions and brass are approved for usage throughout plumbing systems, however brass is utilized where bad water quality exists and galvanized materials have high chances of getting worn away. Brass is a malleable alloy of copper and zinc that has actually remained in use for centuries. Brass fittings are manufactured to IPS and NPT standards and are extremely well compatible with threaded adapters made from other metals and composites.

South End Plumbing specializes in all plumbing leak repairs, so remember, we are just a click away. We also specialize in leak detection – give us a call! South End Plumbing is one of the only companies that will give you a free estimate. Call us at 704-919-1722 or fill out the form online to schedule a visit.