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.
It is Texas Flange's policy to provide customers with ethically procured products and to engage only in responsible procurement practices. Flanges, fittings, and other items supplied to our customers via our own production lines, as well as those of import flange sourcing, are from authorized raw materials. Certain minerals (tin, tantalum, tungsten and gold) produced in conflict-ridden nations, and distributed via supply chains might be used to fund armed forces engaged in illicit activities involving human-rights violations, acts of violence, etc., and consequently such materials are referred to as “Conflict Minerals”. The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 requires companies registered with the SEC to disclose whether the products they manufacture or contract to manufacture contain “Conflict Minerals” that are “necessary to the functionality or production” of those products. Texas Flange does not provide any products, components or other flange materials that contain Conflict Minerals and we are committed to customer service and ensuring that our customers meet their sourcing requirements and obligations. Our flanges are meant to comply with all applicable specs.
To that end, Texas Flange has exercised due diligence to determine the country of origin and manufacture of items supply chain that are of import origin, and this is done in accordance with the OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas and similarly recognized international guidelines. It is our policy that raw material is sourced from smelters that have been determined to be conflict-free smelters or determined to be conflict-free under other trusted traceability projects. We are happy to continue to fill out forms for our customers to ensure that we do not provide flanges and fittings from conflict sources, but let this note serve as a disclaimer that it would not be necessary. We are committed to quality and satisfaction in the flange and fitting industry and look forward to a strong relationship with all of our customers.
Some of our customers often wonder about flatness being an issue with regards to aligning flanges properly on their equipment, or for the purposes of general aesthetics/symmetry for non-industrial applications. To the best of our knowledge, there is no flatness tolerance in any published flange specification. Since flanges are made on lathes from oversized forgings, the probability of having an issue is near zero. That said, one can take a micrometer and check the thickness in multiple places against published thickness tolerances to “flunk” a flange whose flatness is seriously in question. Texas Flange has never had an issue with flatness for any flanges we have supplied to our customers.
In some instances, it is important to take flatness into consideration when machining to certain dimensions. This is almost exclusively a concern when a customer requires a large OD flange made to a very minimal thickness. As an example, if a customer requires a custom ring flange of a 60” diameter made to a half inch thickness, we would not offer machining across the face due to the likelihood of “waffling,” but would offer mill finished from plate. This is essentially an attempt to reduce an issue with flatness for the finished/shipped product flange, and also to ensure the face finish is out of code. In these extreme cases, Texas Flange may propose that your facing is done with Blanchard grinding or some alternative to the typical symmetry of a 125-250 RMS, so that although the industrial standard for face finish is not practically achievable in this particular application, an asymmetric machine finish is provided in order to accommodate the friction needed in the gasket sealing process of your installation.
Texas Flange is always trying to be of the best service to our customers.
Studding outlet flanges (also known as outlet flanges, stud pads, or pad flanges) are made to order items offered in a variety of configurations. The most commonly used studding outlet flange in the industry is the flat bottom type. We also offer them in a shell mount, head mount, or alternate radius in order to set the flanges flush with your tank or vessel. Just let us know the radius and type of mount required and we will provide these flanges according to your application. The least common outlet flange is the tangential mount, which is offset from a center line and therefore lacks symmetry. We provide these outlet flanges according to your submitted drawing, and although the mount detail is a bit more complex, this typically does not affect the lead time in comparison to the other styles.
The majority of outlet flanges have tapped holes as opposed to thru holes. The raised face is standard as with ASME/ANSI flanges, but flat face and RTJ/groove facing is available upon request. Studding outlet flanges come in any material as “normal” flanges, especially in grades ASTM A105 forged carbon steel, A350 LF2 low temp carbon steel, and forged stainless steel grades ASTM F304/L and F316/L. We can also provide these in special alloys as necessary. Give us a call or shoot us an email with your inquiry so we can provide you with the studding outlet flanges you need as fast as possible!
All Texas Flange products come with heat codes for traceability. Each code references a “heat”; a single grouping of forgings created from the same piece of billet in one forging session. Essentially, this heat code is the “DNA” or “fingerprint” of sorts for identifying the physical and chemical composition of our flanges or custom components. Typically, an extra piece is forged to obtain physical traits by destructive testing (referred to as “crashing” a piece) per ASME code. Chemistry values include the percentage of alloying elements such as Carbon, Chromium, Nickel, Sulfur, Phosphorus, Aluminum, and so forth. Physical values are provided on Material Test Reports (MTRs) with respect to the requirements of the material. As an example, some flanges undergo heat treatment processes like normalization or quenching and tempering, and as ASME flanges in pressure classes 400# and above require ASTM A105 carbon steel flanges to be heat treated automatically per code, this information is included in the report.
All of this information is printed on a Material Test Report that certifies the flange material to the appropriate ASTM/ASME specification. Texas Flange provides all flanges with MTRs per EN10204 3.1* at no additional charge. These MTRs are shipped with the flanges ordered or emailed directly to you at your request once the order is completed. Occasionally, our customers will request a C of C (certificate or letter of conformance) to go with their order, and we provide this free of charge as well. Rest assured that providing flanges per the requirements of your purchase order are of utmost importance to us. Quality is critical in our service of providing materials for pressure vessels, refineries, offshore and onshore rigs, pipelines, and a seemingly endless number of alternate industrial applications. Give us a call or shoot us an email with any questions or concerns on your order.
*Note: the former designations 3.1B and 3.1C have been revised to just 3.1 and 3.2, respectively. Current 3.1 meets all requirements of the previous 3.1B.