What is Bronze?
Bronze is one of the original metal alloys. Using copper and tin, metal workers developed a material that was both strong and malleable, meaning it would not crack as easily as something like iron. Bronze has not changed very much, aside from the reduced amounts of lead and the occasional addition of manganese, aluminum, or nickel. Parts made of this material can only be manufactured by casting the material into a mold or by machining a pre-cast bronze ingot.
Bronze has a rough, porous exterior with small cavities in the surface. This is due to the casting process. However, bronze alloys with select additives can hold a polish and are not as abrasive. Bronze has many benefits, including high ductility (resists cracking), corrosion resistance, and low cost. There are tons of uses for bronze valves, including safety relief, flow direction control, shutting off flow, and more! Lead free bronze valves for potable water are available, but they must meet or exceed Clean Water Act lead restrictions.
What is Brass?
Brass is very corrosion-resistant, much like bronze, but is susceptible to breaking down when exposed to high levels of chlorine.Brass is a newer material than bronze. It Is primarily copper and zinc, but is extremely versatile. There are a wide range of brass alloys with varying properties. Brass is also malleable and easy to work with. This makes it easy to cast, forge, heat extrude, or cold draw. Brass is very corrosion-resistant, much like bronze, but is susceptible to breaking down when exposed to high levels of chlorine.
The main benefit of brass valves over bronze is the much lower levels of lead present in the metal. This makes brass safe for drinking water in most cases. Another of the uses for brass valves is as shut-off valves in natural gas lines because of its low . Brass, in just about every case, is a much more effective solution than bronze, but it costs considerably more. The price disparity can be a problem for many people, but it is typically justified.
What's the Difference Between Bronze and Brass Valves?
We have just gone into some detail on the subject of "bronze vs. brass valves," but we will lay out all of the main differences here for easy visualization. Some figures vary between different types of bronze/brass, so do your research if you plan on testing the limits of your valve.
| Bronze | Brass | |
|---|---|---|
| History: | Dates back to ~3500 BC | Dates back to ~500 BC |
| Melting Point: | 1590F (865C) | 1710F (930C) |
| Color: | Muted Gold | Reddish Brown |
| Composition: | Copper, Zinc, Other Additives | Copper, Tin, Other Additives |
| Benefits: | Relatively Inexpensive, Better Corrosion/Rust Resistance than Cast Iron, Somewhat Malleable | Better Corrosion Resistance than Bronze, Ideal for Drinking Water, Very Malleable |
| Drawbacks: | Rough and Porous Surface Susceptible to Gradual Degradation, Sometimes has High Lead Content | Somewhat Expensive, Can Break Down when Exposed to High Levels of Chlorine |
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