Introduction
In the modern industry, the demand for filtered fluids and gases has increased. The proper functioning of the machines requires clean fluids and gases for proper operation. Sintered bronze filters have a variety of shapes, can be used repeatedly, and provide robust performance.
Equipment used in industries such as automotive, hydraulic systems, and fluid pipelines requires filtration to extend its lifespan and reduce wear and tear.
In this article, you will learn about how sintered bronze filters are made and their advantages.
Sintered Bronze Filter Manufacturing Process
Before detailing the manufacturing process for sintered bronze filters, it is essential to know the filter’s chemical composition. The metals used in the manufacturing process are bronze (85–90% copper and 10–15% tin), and these metals are sintered together to form filters. Sometimes, to increase the strength, nickel and zinc could be added as well.
- The first step in the sintering process for sintered bronze filters is powder selection. All the metal powders are added together.
- The size of the particles compressed into a filter determines the filter’s porosity. The metal powder is placed inside a mold and compressed at 100-400MPa.
- The material mixture is heated at 750-850 degreesbelow the melting point of the bronze for sintering.
- The pores are very precise and provide outstanding filtration by 5-100 micronsof pore size.
- The filters formed by the sintering process have a mechanical strength of 5-10 bar and can withstand temperatures up to 250-450 °C.
Advantages of Sintered Bronze Filters
The use of sintered bronze filters offers several advantages, including mechanical strength, heat and corrosion resistance, and a long service life. Let’s get into the details of the benefits of using sintered bronze filters.
Mechanical Strength
Different industries are using sintered bronze filters because of their high mechanical strength.
- The tensile strength of the filter is around 3 to 5 Kg/mm² (approximately 30 to 50 MPa).
- Filters in disc, tube, plate, and cup shapes have pore densities that determine their rigidity. The density of the sintered bronze filter is almost 5 to 6.5 g/cm³.
- High mechanical stability enables the filter to withstand high temperatures and pressures without deforming or cracking.
- The mechanical strength of the sintered bronze filters has made them chemically resistant and enabled their use in chemical filtration.
Heat and High-Temperature Resistance
Many industries use sintered bronze filters in their filtration processes because they can withstand heat and have high-temperature resistance.
- The temperature resistance of the sintered bronze filters depends on the environment in which they are used.
- If filters are used in an oxidizing environment, the temperature rating may be 250 °C (392 °F).
- In a reducing environment, the temperature resistance is higher, namely 450 °C.
Corrosion Resistance
The composition of the sintered bronze filter has bronze, copper, tin, and sometimes zinc or nickel. All these metals have inherited corrosion resistance. Sintered bronze filters have high corrosion resistance, making them suitable for use with corrosive materials. These filters are highly resistant to chemical and environmental corrosion due to the alloy combination used in manufacturing.
High Porosity and Permeability
The manufacturing of sintered bronze filters has created a network of interconnected pores on the surface.
- The interconnection of the pores has created the permeability in the filters. This provides a greater surface area for the filtration.
- The benefit of using uniformly distributed sintered bronze filters is that the fluid maintains its pressure during the filtration.
- You can filter large amounts of material using these filters.
Long Service Life
The thermal and mechanical strength of the filters has enabled them to be used in harsh environments. The average lifespan of a sintered bronze filter in a hydraulic system is around 10 years with proper maintenance. Plastic or ceramic filters cannot be used for extended periods and will wear out.
Economical and Efficient
The sintered bronze filters can be reused after the cleansing process. The process can cleanse these filters of:
- Backlashing
- Ultrasonic filtration
- Chemical filtration
The filters have a filtration efficiency of around 0.1 μm to 250 μm, allowing them to filter out silicon dioxide, rust, and sediment. The approximated efficiency of the sintered bronze filter is around 98%.
Applications
Sintered bronze filters have applications in many industries.
· Compressed Air System
In a compressed air system, sintered bronze filters are used to remove water, particles, and oil mist. That will help prevent damage to the system’s components, such as valves and regulators.
· Hydraulic system
In hydraulic systems, sintered bronze filters protect pumps and control valves from contamination by foreign particles and dust. It will help the system to maintain the integrity of its parts.
· Medical and Food Equipment
In the medical and food industries, filters are used to sterilize air. As they are easy to clean and sanitize, they can be used in nozzles and precision dispensers.
· Chemical Industries
Sintered bronze filters are chemically resistant and can be used in chemical industries to filter chemicals. The chemical’s flow is maintained during the process, and the reaction is controlled.
· Automotive Industry
The automotive industry uses sintered bronze filters to improve vent breathability, provide fuel and oil filtration, and maintain a controlled emissions system.
Sintered Bronze Filters vs. Sintered Stainless Steel
| Features | Sintered Stainless Steel | Sintered Bronze Filters |
| Material | Stainless steel powder 316L or 304L | Copper alloy and bronze powder |
| Mechanical strength | Very high | Moderate |
| Filtration accuracy | 2–200 µm precise | High accuracy |
| Corrosion resistance | Excellent | Good |
| Temperature resistance | up to 600°C | up to 450°C |
| Chemical resistance | Weak | High |
| Durability | Very long and can be reused | Long and reused |
| Cost | Higher | Lower |
Conclusion
Sintered bronze filters are dependable, economical, and long-lasting options for filtration in numerous industries. In high-demand industries such as hydraulic systems, compressed air units, and chemical processing plants, and for severe environments. Their great mechanical strength, corrosion resistance, and high-temperature withstanding are helpful. Uniform porosity guarantees effective filtration at consistent flow rates.
Their reusability makes them more valuable economically. Sintered bronze filters are also a cheaper alternative to stainless steel filters and have considerably longer service lives and high chemical resistance. In general, sintered bronze filters are necessary to protect equipment, provide cleaner, more efficient operation, and improve overall efficiency.