Texas Flange supplies a wide variety of specialty alloys in flanges and fittings for the global industries which we serve. We’ve noted a few differences in some of the more popular chrome and nickel products which are used in various refining, nuclear, petrochemical, corrosion process, and treatment applications.
304H – UNS S30409
A high carbon variant of the most commonly used and extremely versatile stainless steel in the flange industry. 304H is an austenitic chromium stainless which contains a carbon content range of .04 – .10 to help with heat resistance for high temperature applications. It also carries all of the general attributes and service properties of regular grade 304 stainless steel.
316H – UNS S31609
Similar in approach to 304H, grade 316H is a high carbon variant of regular grade 316 stainless steel, which contains a small percentage of molybdenum for use in marine grade applications. This austenitic grade of stainless utilizes a higher carbon content for use in higher temperature service, much like its cousin grade 304H. Though it is less commonly used, it is still commercially available.
317/L – UNS S31700 / UNS S31703
An austenitic chromium grade containing molybdenum, and similar to grade 316, except with a higher value of stress resistance, increased tensile strength, higher service in elevated temperature, and general resistance to corrosion from chloride, sulfuric solutions, or other corrosive media. The low carbon option (L) can be selected for a more optimal weld requirement.
310/310S – UNS S31000 / UNS S31008
A stainless grade with excellent workability, utilized in heat exchanger applications and projects with elevated temperatures involving high salinity. This grade contains an increased chromium and nickel content and has elevated characteristics of oxidation and corrosion resistance when compared to more common stainless grades such as 304 and 309.
321/321H – UNS S32100 / UNS S32109
An austenitic grade stainless containing over 4 or 5 times the level of titanium as it does in carbon, with a maximum titanium value of 0.70%. This material has a high intergranular corrosion resistance and is well utilized in high heat applications in the aerospace industry such as aircraft jet engine manifolds and exhaust components.
347/347H – UNS S34700 / UNS S34709
A stainless grade containing a small percentage of columbium and tantalum for stabilization purposes. Commonly used in the combined high heat and corrosion environments of refineries, power generation, and airline service, this austenitic alloy retains better properties in corrosive environments comparted to similar alloys 321 and 317.