NIBCO Wrot And Cast Copper Tube Fittings

NSF / ANSI compliant adapters, caps, tees, elbows and couplings used in plumbing and HVAC applications to provide leak-proof connections

What should the users know to assure a leak-free installation of copper unions?

• Users should make sure that the ground-joint / mating area of the union (thread portion) is free of scratches or nicks.
• They should apply beeswax or spray a food-grade silicone spray on the ground-joint area to enhance seating.
• The line alignment of the union should not put any lateral stress on the ground-joint seal.
• The ground-joint area should be cleared of any excess solder (droplets) generated during the soldering process.

Can fittings made of dissimilar metals (i.e., copper and iron) be joined together without the use of dielectric insulators?

• Yes, fittings made of dissimilar metals like copper, iron or steel can be joined successfully in most cases without using dielectric insulators while preventing corrosion. Some factors to consider before joining these dissimilar metals are:
• Composition of the two joining metals.
• The fluid flow rate through the fitting.
• Presence of chemicals in the fluid that may enhance or destroy protective films inside fittings.
• A dielectric separator is not needed unless the surface area of the less noble (steel) material is less that 5% of the more noble (copper) material.
• Users should take note of local code requirements.

What are some common causes of Nibco copper fittings failure?

• Excessive fluid velocity may cause corrosion or material erosion. Velocity limits of the copper piping system are generally 5 - 8 feet per sec for cold water and 2 - 3 feet per second for hot water( temperature greater than 140 degrees F / 60 degrees C). The presence of burred tube ends, bends & dents may also lead to localised high-velocity conditions & turbulence.
• Nibco copper fittings may also corrode due to diverse pH (acidic or basic) fluids, soil / environmental conditions or high stress.
• These fittings should also not be used with fluids having a pressure greater than the maximum allowed pressure.

What is the difference between diverse materials used for making Nibco copper fittings?

• Copper materials have thermal & electrical conductivity. It shows some resistance to impact, wear or corrosion. Copper has antibacterial and antimicrobial properties for use in food-grade applications.
• Brass materials generally have higher strength than pure copper materials. They provide a lustrous appearance for use in decorative or architectural applications. Brass is added with additional metals / alloy for higher melting point, dezincification resistance or greater corrosion resistance.
• Bronze provides excellent thermal conductivity and corrosion resistance in marine applications.

How to choose between Nibco cast copper & wrot copper fittings?

Users can choose between the different types / materials of copper fitting based on their manufacturing difficulty and cost-effectiveness. For example, a drop ear elbow is generally made by casting process as it is not cost-effective to manufacture using the wrot process. Whereas, copper fittings, such as a 90-degree elbow, are cost-effective to form using the wrot process.