Stainless steel 316 rings are annular sealing components made of SS316 stainless steel, used to seal flange connections in pipelines, valves, pressure vessels, and various equipment. HT PIPE supply all different types and scales of rings. Please feel free to contact us for further product information and pricing.
material composition of ss316 material
The material composition of SS316 stainless steel is the foundation of its excellent performance. This alloy contains 16-18% chromium, 10-14% nickel, and 2-3% molybdenum, along with smaller amounts of carbon, manganese, silicon, phosphorus, and sulfur. The addition of molybdenum significantly improves the material's resistance to pitting and crevice corrosion in chloride environments, making SS316 flange rings more suitable for use in more corrosive environments than standard 304 stainless steel flange rings.
mechanical properties of 316 steel
Stainless steel 316 rings boasts a tensile strength of at least 620 MPa and a yield strength of at least 310 MPa. This high strength enables SS316 flange rings to withstand the high pressures and high bolt preloads found in pipeline systems, preventing seal failure due to plastic deformation.
The material also exhibits an elongation of at least 30% and a reduction of area of 40%, demonstrating its excellent toughness and deformability, enabling it to maintain a consistent sealing interface through appropriate deformation during system pressure fluctuations or temperature changes.
Type of stainless steel 316 ring
Flat Sealing Rings and Gaskets
Flat sealing rings are the most basic type of SS316 flange ring, primarily used for connecting flat and raised-face flanges. These sealing rings are relatively simple in structure, typically made from solid Stainless steel 316 rings by turning or stamping. They offer a sturdy structure and high pressure resistance.
In low-pressure and low-temperature applications, a simple SS316 metal flat gasket can provide an effective seal. However, in medium- and high-pressure applications, they often require combination with other soft sealing materials or a softer coating on the metal flat gasket to enhance sealing effectiveness.
Spiral Wound Gaskets
Spiral wound gaskets are one of the most commonly used and important types of SS316 flange rings. They are constructed by alternating, overlapping, and spirally wound preformed "V" or "W"-shaped SS316 stainless steel strips with non-metallic filler materials (such as graphite, asbestos, or polytetrafluoroethylene).
This unique structural design gives spiral wound gaskets excellent resilience and high pressure-bearing capacity, making them particularly suitable for applications with uneven loads, prone to joint relaxation, cyclical temperature and pressure fluctuations, and shock or vibration.
Vacuum Flange Centering Rings
Vacuum flange centering rings are a special form of Stainless steel 316 rings for vacuum systems, primarily used for sealing connections with standardized vacuum flanges such as ISO, KF, and NW. These centering rings are typically made of SS304 or SS316L stainless steel and incorporate O-rings made of various elastomeric materials (such as Viton rubber, silicone, or EPDM).
They are secured between flanges using bolts or single or double-jaw clamps. Vacuum centering rings are designed with precise dimensional control and excellent surface quality to ensure the required sealing performance even in high vacuum environments.
Combined Sealing Gaskets
Combined sealing gaskets are composite sealing components made by integrally bonding and vulcanizing an SS316 metal ring and a rubber sealing ring. They are primarily used for sealing in hydraulic systems, threaded pipe joints, and screw plugs. This unique design combines the strength of metal with the elasticity of rubber.
The metal ring (usually SS316 stainless steel or carbon steel) provides structural support and prevents excessive extrusion of the rubber portion, while the rubber ring (common materials include NBR, FKM, EPDM, etc.) elastically deforms to fill microscopic irregularities in the connecting surface, achieving a tight seal.
How to Correctly Select and Use SS316 Flange Rings
Confirm Standards and Specifications: Stainless steel 316 rings is essential to clearly identify the design standards for the piping system, such as ANSI/ASME B16.5, DIN, and EN. Determine the nominal diameter, pressure rating, and sealing surface type of the flange ring.
Evaluate the operating conditions: Analyze the media characteristics, concentration, temperature, pressure, and, particularly, chloride ion content in detail to determine whether Stainless steel 316 rings is adequate for the application.
Mating flange consistency: Ensure that the mating flanges being connected have the same pressure rating, dimensional standards, and are made of similar materials to avoid galvanic corrosion.
Proper installation:
- Use appropriate gaskets to ensure a tight seal.
- Tighten bolts evenly in a symmetrical, cross-section sequence to the specified torque value.
- In corrosive environments, consider using SS316 bolts and nuts.
Regular maintenance and inspection: Regularly inspect bolt tightness and sealing surfaces for corrosion or damage to prevent potential problems.
