I know you are probably wondering why brass valves are common in most domestic and industrial applications. Or, you would like to know which types of brass alloy grades are perfect for valve manufacturing.
Well, to explain this, we will begin by explaining what a valve is, and have a quick overview of brass material composition. Then later explore why brass is good for valve manufacturing.
Putting all these together will help you understand why we use brass to make valves.
Valve
A valve is a special accessory that regulates, redirects, stops, or controls fluid flow. Remember, the fluid can be gases or liquids.
Usually, valves come in different configurations depending on the specific functions. Therefore, whenever you are choosing valve material, it must satisfy certain flow requirements. In most cases, brass meets this special criterion as you will learn shortly.
Ideally, brass valve types come in many configurations such as brass ball valves, brass angle valves, and brass check valves, just to mention a few.
Brass Material for Making Valves
Brass material is known for being superior:
- Resistance to most chemicals
- Strength
- Durability
When it comes to color, brass is yellow in appearance. Still, the color may vary from brown to gold depending on the elements’ composition.
Usually, the brass for valve fabrication has copper and zinc as the main alloying elements. However, varying the material composition while adding other elements produce various alloys.
For example, you may have:
| Element Composition | Remarks |
| · 59 to 63% Cu, 0.070% Fe, 0.3% and 40% Zn | · Standard brass as classified by the UNS C28000 |
| · 60 to 63% Cu, 35.5% Zn, less than 0.35% Fe, and 2.5 to 3.7% Pb | · Refers to the alloy 360 brass |
| · 30% Zn, 1% tin, and reaming % Cu plus other elements in a negligible composition | · Widely known as admiralty brass with the ability to prevent dezincification |
| · 0.08 to 0.15% arsenic, 35 to 37% Zinc, 0.2% (max) Tin, and 0.2% (max) Iron | · DZR brass is known for exceptional resistance to dezincification |
Depending on your application requirements, your brass valve manufacturer will help you choose a perfect grade.
Suitable Brass Alloys for Fabricating Valves
There are many brass alloys on the market today. Therefore, there is only specific brass used in the valve fabrication process. Of course, these are attributed to performance and certain safety concerns.
Therefore, if you are fabricating brass valves, you may consider these alloy grades:
· DRZ Brass
When it comes to high-performance valves, you should consider dezincification-resistant brass (DRZ) brass valves. Such valves are known for high corrosion resistance.
In most cases, you will find the valve body made from DRZ brass. However, certain sections can be made from stainless steel for the handle. Or, in the case of a ball valve, the ball can be made from chrome-plated brass.
· CW617N / CZ122 Brass
CW617N brass is also common in valve fabrication. This brass alloy is known for superior hot working properties, besides being easy to machine. Again the CW617N brass is susceptible to dezincification.
Apart from these two popular grades, others include Cartridge Brass (yellow brass), and red brass, just to mention a few. The CW614N brass, which is also called the China normal brass or HPb57-3 is also commonly used to make valves.
As a rule, health consideration is key when choosing brass material for valves. For instance, when designing brass valves for water drinking systems, avoid grades with lead (Pb). It is actually for this reason that you will find lead-free brass valves.
The idea of lead-free brass valves is so serious to an extent that there are laws in place such as the AB1953 regulations in the USA. It ensures that brass piping systems including brass valves and fittings adhere to the recommended lead requirement.
Furthermore, such regulations are also guided by the RoHS, which stipulated the allowable lead composition in brass piping systems.
How Valve Fabrication Influences Brass Alloy Grade
Fabricating brass valves and fittings require many techniques and processes. Depending on the valve type or part, forging, welding, extrusion, cold drawing, casting or polishing may be used.
Therefore, you must choose brass material that best suits the specific fabrication process. Actually, brass meets most fabrication criteria for the valve manufacturing process.
Why use Brass for Valves Fabrication
As a valve material, brass offers many benefits. This makes brass valves a perfect choice for many practical uses. Let’s explore this in detail:
1. Corrosion Resistance
Fabricated brass valves have a thin protective layer that makes them resistant to most environmental conditions. Usually, the protective layer forms a brass surface on exposure to oxygen.
Due to superior corrosion resistance, brass valves and fittings are suitable for most environmental conditions. This includes even marine environments.
2. Ease of Fabrication and Machining
Producing brass valve types require many fabrication and machining operations. For instance, depending on the type of brass valve, you may forge or extrude brass water valve parts.
At the same time, you may weld the brass valve handle to make a complete section.
The fact that you can easily fabricate or machine brass makes the material a perfect choice for many applications. Depending on your unique application of brass valves, customization is straightforward.
Furthermore, brass exhibits superior malleability properties. Therefore, you can mold brass to make complex valve parts and designs.
3. Superior Mechanical Properties
With tensile strength varying between 338 and 469Mpa, brass valves can withstand high pressure and load. Even when subjected to high stress, the valves will remain intact.
However, as you choose these valves, be clear on the pressure rating.
4. Temperature Resistance
Under normal circumstances, brass valves and fittings can withstand between -198° C and 204°C. Of course, this will depend on the valve design and configuration. It is actually for these reasons that you will find brass in most heat exchanger systems.
5. Anti-bacterial Property
One of the main reasons why brass water valves are popular is their anti-bacterial and biofouling properties. Usually, this will prevent possible contamination in the piping system.
Remember, copper is a key alloying element of brass. It is responsible for the anti-bacterial property.
6. Brass is Inert
To some extent, brass is inert. Therefore, brass valves and fittings are compatible with most fluids. The application of brass valves in water, gas, and oil does not show any form of deterioration or contamination. For this reason, you will find brass piping systems in many industries today.
7. Brass is Affordable
Comparing brass to stainless steel valves, the latter is more expensive. Therefore, for applications that are not very demanding, choosing brass valves is a cost-effective option.
8. Brass is Durable
Brass valves and fittings are durable. Even at high temperatures and pressure, brass valve types will maintain their integrity for a long time.
But even as you choose brass for your valves, there are certain challenges you will deal with such as:
- Unless the brass used in the valve is lead-free, they are not FDA-approved like the stainless steel valves.
- For specialized applications that require superior corrosion resistance, other materials like stainless steel valves are a perfect choice.
- Comparing brass valves vs bronze valves, the latter tends to have a porous finish. At the same time, brass valves tend to have higher fatigue stress resistance.
Conclusion
The brass used in valves offers many benefits. However, you must choose an acceptable brass alloy grade for your valve fabrication.
At D&R, we will help you choose a suitable brass alloy grade for your valves – contact us now for free consultations.