At times, choose between bronze valves and brass valves can be a difficult task. Well, the two valves share many properties. However, there are distinct features making each valve suitable for only specific applications.
Let’s explores more about these valve types.
What is Bronze Valve?
This is a valve that is made out of bronze material which is an alloy made out of copper, tin, and other additional metals like nickel, aluminium, and manganese. The valve is made by casting. That is, a hot molten form of bronze is put in a mold of desired shape and let to cool and solidify.
What is Brass Valve?
This is a valve that is made out of brass material which is an alloy that is made up of copper and zinc. The valve can be processed by use of either cold drawing, forging, casting or heat extrusion. Brass is easy to maintain, is flexible and also adaptable. Brass valves are more durable and guarantee optimal performance.
Appearance of the Valves
Bronze valve has a reddish brown look in color and has a surface that is rough and serrated due to the casting procedure used to make the product. Brass on the other hand has a dull pale yellow tint appearance which looks like gold in color. Furthermore, it has a smooth surface due to the procedures used in production.
Chemical Composition of the Valves
Brass is contains copper and zinc alloy while bronze is comprised of copper as the main component, and tin. In in some cases an addition of other metals such as nickel, aluminium and manganese.
Comparing Corrosion Resistance
Brass can be corroded when exposed to water with chlorine. Brass is also prone to Dezincification which is a process where zinc corrodes away leaving excess copper in brass. This can be easily dealt with by use of a Dezincification-resistant brass which is covered with a protective coating.
Bronze is better compared to brass because of its good Dezincification-resistance. However bronze can get corroded by metallurgical flaws.
Comparing Strength and Durability
The durability and strength of bronze and brass are both good. When comparing the two, bronze valve it stronger with a tensile strength of 350 – 635MPa while brass has a tensile strength of 338 – 469MPa. This makes bronze is more durable compared to brass, due to the fact that bronze has better tensile strength than brass
Price of Bronze Valve vs Brass Valves
According to the raw materials used in making the two valves, bronze is much expensive compared to brass. This is due to the fact that zinc found in brass is less expensive and easy to find. Also brass valve is produced with low expenses compared to bronze which must be further polished due to the uneven surface.
Working Temperature & Heat Resistance of Brass Valve and Bronze Valve
Brass has a melting point of 1710 degrees Fahrenheit which is about 930 0C. Whereas bronze melts at a temperature of 1590 degrees Fahrenheit which is about 865oC. This means that a brass valve is much more tolerant to heat compared to bronze valve.
Manufacturing of Bronze Valve and Brass Valve
Bronze valves are made by casting method where a hot molten form of bronze is put in a mold of desired shape and let to cool and solidify.
Brass valves are made by various methods including cold drawing, forging, casting or heat extrusion. Due to the reason of uneven smooth surface obtained from casting, forging is usually preferred.
Lead Content in Bronze Valves Compared to Brass Valves
The lead content of bronze is higher compared to that of brass. Brass has a 3% lead capacity of the whole weight while bronze has a 5% lead capacity. Due to this and the fact that bronze discharges lead, it is much suitable to use brass in movable water.
Uses of Bronze Valves and Brass Valves.
Bronze valves are used in the following areas.
- Marine applications.
- Safety relief.
- Petrochemical applications.
- Flow shut-off
- Flow control.
Brass valves are used in the following areas.
- For flow control.
- Portable water flow.
- Flow directional control.
- Natural gas shut-off
- Liquid and air shut-off
With the information in this guide, you can definitely decide when to choose bronze valve or brass valves. In case you have any questions on any valve types, D&R team is here to help – contact us now.