What is the Difference Between SS304 and SS316 Filter Housings?

Stainless Steel Filter Housings have been widely used in liquid filtration systems, and the choice of material is directly related to the service life, filtration effect and operating cost of the equipment. Therefore, it is very important to understand the difference between SS304 and SS316 in filter housing applications. This article will analyze the difference between SS304 and SS316 in detail, focusing on the 3 core dimensions of corrosion performance, pressure and temperature resistance, and application areas, to help you make a more informed material choice in the international trade of water treatment equipment.

1. What is the Stainless Steel 304 Filter Housing?

SS304 filter housing is a filter equipment shell made of austenitic SS304, with a basic composition of 18% chromium and 8% nickel, and does not contain molybdenum. Its advantages lie in its excellent cost performance and good processing performance. It is suitable for filtering conventional water quality environments with low chloride ion concentrations and corrosive liquids such as weak acids and weak alkalis.

2. What is the Stainless Steel 316 Filter Housing?

SS316 filter housing is a precision filtration equipment made of austenitic stainless steel containing molybdenum. Compared with SS304, its biggest feature is the addition of molybdenum, which makes it have better resistance to chloride ion corrosion and is suitable for harsh environments such as coastal areas and chemical industry. The surface can be electropolished at medical grade to meet the high hygiene standards of pharmaceuticals and food. Stainless steel 316 filter housing is the first choice for high-end water treatment systems.

3. Corrosion Performance Comparison of SS304 and SS316

Corrosion performance is the primary consideration when selecting filter materials, which directly determines the service life of the equipment in a specific water quality environment. Although both SS304 and SS316 are austenitic stainless steels, there are significant differences in corrosion resistance. The standard composition of 304 stainless steel is chromium and nickel, which gives it good basic corrosion resistance and can resist atmospheric corrosion and corrosion in most freshwater environments.

In contrast, SS316 adds molybdenum to SS304, a key difference that greatly improves its corrosion resistance. The addition of molybdenum significantly enhances the material's ability to resist chloride ion corrosion, making SS316 filter housings one of the main choices for water treatment systems in coastal areas. For water treatment companies, accurately assessing the water quality conditions of the target market is the key to selecting the filter housing material.

4. Comparison of Pressure and Temperature Resistance of SS304 and SS316

During operation, stainless steel filter housings not only need to resist water corrosion, but also withstand pressure and temperature changes within the system. The differences between SS304 and SS316 in terms of pressure and temperature resistance directly affect their applicability in different water treatment applications. In terms of temperature resistance, compared with SS304 filter housings, SS316 filter housings can better maintain good mechanical properties and corrosion resistance in high temperature environments. In actual water treatment applications, temperature fluctuations are often accompanied by pressure changes. This means that at the same design thickness, the SS316 housing can withstand higher system pressures.

5. Differences in Application Between SS304 and SS316

As a professional water treatment company, understanding the applicability of 304 and 316 Stainless Steel Filter Housings in different application scenarios can help you provide more professional advice to your customers and optimize your product portfolio. The two materials have distinct application areas in the water treatment industry due to their performance differences.

SS304 filter housings have become the first choice for most conventional water treatment applications due to their good cost-effectiveness. This includes municipal drinking water treatment, industrial circulating water systems, primary filtration stages of sewage treatment plants, etc. In these applications, the water quality is relatively controllable and the chloride ion content is low, and SS304 is fully able to meet the requirements. Especially for projects with limited budgets or large-scale water treatment facilities, the use of SS304 housings can significantly reduce the overall investment cost without significantly sacrificing equipment reliability.

In contrast, SS316 filter housings are mainly used in water treatment systems in harsh environments. This includes water treatment facilities in coastal areas, chemical wastewater treatment systems, and high-purity water systems in the pharmaceutical and food industries. In these applications, high chloride ion content, acidic conditions, or strict hygiene requirements make the excellent corrosion resistance of SS316 filter housings a necessity. From a geographical distribution perspective, SS316 housings should be given priority when exporting water treatment equipment to coastal areas. Similarly, 316 stainless steel filter housings are also a more reliable choice for water treatment projects in areas with high salinity groundwater.

It is worth noting that in some moderately corrosive applications, a hybrid strategy can be adopted: use SS316 in key locations (such as flange connections, weld areas), and SS304 in other locations. This design can control costs while ensuring corrosion resistance in key areas. For large filter housings, this differentiated material selection can save material costs for the entire project.