What is Brass?
What is Bronze?
Why is Bronze Corrosion-Resistant?
Differences Between Brass Valves and Bronze Valves
Curious about the differences between brass valves and bronze valves? Here’s a concise answer:
Brass valves are more cost-effective and have better antimicrobial properties.
Bronze valves offer superior wear resistance and corrosion resistance.
Let’s delve deeper into the distinctions and reasons behind them.
Brass and bronze are crucial copper alloys we use all the time, with different compositions leading to varied performance and applications. To understand why brass and bronze valves are different, we need to know what makes brass and bronze tick.
What is Brass?
Brass is the most widely used copper alloy, primarily composed of copper and zinc. Copper content typically ranges from 50% to 95%, with zinc content between 5% and 50%. Special Brass often includes a small amount(usually 1%-6%) of tin, aluminum, manganese, iron, silicon, nickel, or lead may be added to enhance corrosion resistance, strength, hardness, and machinability, forming specialty brasses. Such as High Tensile brass/DZR brass/Naval brass.
What color is brass?
Brass exhibits a golden-yellow color, making it an attractive natural material. Its surface color gradually changes over time.
What are the properties of brass?
High hardness, wear-resistant, corrosion-resistant, low friction coefficient, antimicrobial, easily machinable
Brass is commonly used in manufacturing valves, water pipes, air conditioning connection pipes, and radiators.
Common brass grades used for valves:
| Material | Alloy No. | Cu% | Pb% | Sn% | Zn% | Fe% | P% | Ni% | Al% |
|---|---|---|---|---|---|---|---|---|---|
| Brass | CW511L | 61-63 | 0.2 | 0.1 | Rem. | 0.1 | – | 0.1 | 0.05 |
| Brass | CW602N | 61-63 | 1.7-2.8 | 0.1 | Rem. | 0.1 | – | 0.3 | 0.05 |
| Brass | CW614N | 57-59 | 2.5-3.5 | 0.3 | Rem. | 0.3 | – | 0.3 | 0.05 |
| Brass | CW617N | 57-59 | 1.6-2.5 | 0.3 | Rem. | 0.3 | – | 0.1 | 0.05 |
| Brass | C46500 | 59-62 | 0.2 | 0.5-1 | Rem. | 0.1 | – | – | – |
| Brass | C87850 | 75-78 | 0.02*-0.09 | 0.3 | Rem. | 0.1 | 0.05-0.2 | 0.2 | – |
What is Bronze?
Bronze is primarily an alloy of copper and tin. Copper content usually ranges from 75% to 95%, with tin content between 5% and 25%. Small amounts of tin, aluminum, manganese, iron, silicon, nickel, or lead may be added to improve corrosion resistance, strength, hardness, and machinability, forming specialty bronzes.
What color is bronze?
Freshly machined bronze appears golden-brown, but ancient bronze artifacts buried in soil turn greenish due to oxidation.
What are the properties of bronze?
High hardness, high plasticity, wear-resistant, corrosion-resistant
Common bronze grades used for valves include:
| Material | Alloy No. | Cu% | Pb% | Sn% | Zn% | Fe% | P% | Ni% | Al% | Bi% | S% | Sb% | Si% |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bronze | C83600 | 84-86 | 4-6 | 4-6 | 4-6 | 0.3 | 0.05 | 1 | 0.005 | – | 0.08 | 0.25 | 0.005 |
| Bronze | C89833 | 86-91 | 0.09 | 4-6 | 2-6 | 0.3 | 0.05 | 1 | 0.005 | 1.70-2.7 | 0.08 | 0.25 | 0.005 |
| Bronze | C90300 | 86-89 | 0.3 | 7.5-9 | 3-5 | 0.2 | 0.05 | 1 | 0.005 | – | 0.05 | 0.2 | 0.005 |
Why is Bronze Corrosion-Resistant and Wear-Resistant?
Bronze contains a relatively high amount of tin. When exposed to air, tin reacts with oxygen, forming a protective tin oxide layer on the bronze surface. Tin oxide is smooth and hard, providing excellent protection for bronze, and reducing the release of metal elements and environmental corrosion.
Differences Between Brass Valves and Bronze Valves:
Machinability:
Brass valves are easier to machine due to lower hardness and excellent flexibility, and they are suitable for complex structures and high surface smoothness requirements. Bronze valves can also be machined into complex structures at a higher cost.
Wear Resistance:
Bronze valves exhibit superior wear resistance compared to brass valves, making them more suitable for applications involving abrasive fluids or frequent operation.
Corrosion Resistance:
Both materials offer good corrosion resistance, but bronze performs better, especially in marine environments where bronze valves have stronger resistance to dezincification corrosion.
Cost:
Due to lower material and manufacturing costs, brass valves are more cost-effective than bronze valves.
Thermal Expansion:
Bronze has a lower thermal expansion coefficient, making bronze valves more stable in applications with significant temperature fluctuations.
Antimicrobial Properties:
Both materials possess antimicrobial properties, but brass is generally more effective in this aspect, and potentially more beneficial in bacterial growth prevention applications.
In conclusion, bronze valves have a longer service life and are more suitable for environments requiring corrosion resistance, wear resistance, and high-pressure tolerance, especially in industrial and marine applications. Brass valves are more cost-effective and a better choice for standard environments. Brass valves are also suitable for applications with higher antimicrobial requirements and complex valve designs.
Bmag Valves can provide various valves to meet your needs, chat with our 24/7 customer service.
