| 304 Stainless Steel | S30400 | Covered as a stainless-steel bar or shape grade | Machined bar, forged boss, socket, small custom nozzle, or reinforcement component | General-purpose austenitic stainless steel with good forming and welding performance. Nominal chromium-nickel alloy; not preferred for sustained chloride exposure. | Usually nonmagnetic when annealed; cold work may increase magnetism. | General atmospheric, food-processing, water, and mildly corrosive services. | ASTM A240 ASTM A312 ASTM A403 ASME B16.5 | Confirm solution-annealed condition, heat number traceability, weld procedure qualification, and corrosion compatibility with chlorides. |
| 304L Stainless Steel | S30403 | Covered as a stainless-steel bar or shape grade | Machined or forged nozzle neck, flange hub, branch connection, and welded irregular fitting | Low-carbon version of 304. Reduced risk of chromium-carbide precipitation during welding, especially in thin sections and welded assemblies. | Usually nonmagnetic when annealed; cold work may cause partial magnetism. | Welded vessels, piping, sanitary systems, and moderate-corrosion environments. | ASTM A240 ASTM A312 ASTM A403 WP304L ASME Section IX | Often preferred over 304 for welded nozzles. Verify post-weld cleaning, pickling or passivation, and intergranular-corrosion requirements. |
| 316 Stainless Steel | S31600 | Covered as a stainless-steel bar or shape grade | Machined nozzle body, forged outlet, threaded connection, or corrosion-resistant insert | Molybdenum-bearing austenitic stainless steel with better resistance to pitting and crevice corrosion than 304 in many chloride-containing environments. | Usually nonmagnetic when annealed; cold work may increase magnetism. | Marine atmosphere, chemical processing, brine, pharmaceutical, and chloride-moderate service. | ASTM A240 ASTM A312 ASTM A403 WP316 ASME B16.11 | Check chloride concentration, temperature, crevice geometry, surface finish, and galvanic compatibility with adjoining metals. |
| 316L Stainless Steel | S31603 | Covered as a stainless-steel bar or shape grade | Welded irregular nozzle, sanitary outlet, vessel branch, forged hub, or machined connection | Low-carbon molybdenum-bearing austenitic stainless steel. Strong choice for welded parts where corrosion resistance after fabrication is important. | Usually nonmagnetic when annealed; cold work may cause partial magnetism. | Welded chemical, pharmaceutical, food, marine, and water-treatment equipment. | ASTM A240 ASTM A312 ASTM A403 WP316L ASME BPE | Specify low-carbon chemistry, full weld penetration where required, internal surface finish, passivation, and boroscope inspection for sanitary service. |
| 321 Stainless Steel | S32100 | Covered as a stainless-steel bar or shape grade | High-temperature forged or machined nozzle, expansion-line connection, and welded branch | Titanium-stabilized austenitic stainless steel designed to reduce harmful carbide precipitation after exposure to elevated temperatures. | Usually nonmagnetic when annealed; cold work may increase magnetism. | Elevated-temperature service, thermal cycling, exhaust systems, and hot process equipment. | ASTM A240 ASTM A312 ASTM A403 WP321 ASME Section VIII | Confirm titanium stabilization, design temperature, thermal expansion allowance, and weld-metal compatibility. |
| 347 Stainless Steel | S34700 | Covered as a stainless-steel bar or shape grade | High-temperature nozzle neck, forged branch, and welded pressure-vessel connection | Columbium-stabilized austenitic stainless steel with good resistance to sensitization during elevated-temperature exposure. | Usually nonmagnetic when annealed; cold work may increase magnetism. | High-temperature chemical equipment, heat exchangers, and thermal-cycle applications. | ASTM A240 ASTM A312 ASTM A403 WP347 ASME Section VIII | Review stabilization requirements, service-temperature history, thermal fatigue, and the qualified welding consumable. |
| 410 Stainless Steel | S41000 | Covered as a stainless and heat-resisting steel bar or shape grade | Machined nozzle, wear-resistant outlet, valve-related component, or high-strength fitting | Martensitic stainless steel offering higher hardness and strength than common austenitic grades, with lower general corrosion resistance. | Magnetic. | Moderate corrosion, abrasion, steam, petroleum equipment, and wear-related service. | ASTM A276 ASTM A479 ASTM A182 F6a ASME B16.11 | Specify heat-treatment condition, hardness range, toughness needs, machining allowance, and protection against chloride stress-corrosion conditions. |
| 17-4 PH Stainless Steel | S17400 | Covered as a precipitation-hardening stainless-steel bar or shape grade | High-strength machined nozzle, compact forged outlet, instrumentation connection, or pressure-retaining insert | Precipitation-hardening martensitic stainless steel. High strength is obtained through controlled solution treatment and aging. | Magnetic. | High-strength components exposed to moderate corrosion and limited-to-moderate temperature. | ASTM A564 ASTM A693 ASTM A705 ASME Section VIII | State the required condition, such as H900 or H1150, and verify hardness, toughness, dimensional stability, and weld-repair restrictions. |
| Duplex 2205 | S31803 / S32205 | Not normally selected under ASTM A276 unless the exact product specification and grade are confirmed; use a duplex-specific product standard where applicable | Forged or machined nozzle, branch connection, heavy-wall outlet, and corrosion-resistant pressure component | Austenitic-ferritic duplex stainless steel with high strength and strong resistance to chloride pitting and stress-corrosion cracking compared with many 300-series grades. | Magnetic. | Chloride-bearing process streams, offshore equipment, seawater-related service, and chemical plants. | ASTM A182 F51 ASTM A240 ASTM A790 ASTM A815 | Control solution-annealing temperature and cooling rate; verify ferrite balance, phase balance, impact properties, and qualified duplex welding procedure. |
| 6% Moly Super Austenitic Stainless Steel | Common examples include S31254 and S32654 | Generally specified through product standards other than standard ASTM A276 purchasing routes | Specialized forged or machined nozzle for severe chloride and chemical service | High-alloy austenitic stainless steel with substantially improved pitting resistance over 304 and 316L in demanding chloride environments. | Usually nonmagnetic when annealed; cold work may increase magnetism. | Seawater, concentrated chlorides, flue-gas scrubbers, pulp-and-paper, and aggressive chemical service. | ASTM A182 ASTM A240 ASTM A312 ASTM A403 | Require exact alloy identification, PREN or equivalent corrosion assessment, heat treatment, PMI, surface decontamination, and weldability review. |
| Carbon Steel, Pressure-Vessel Grade | Grade-dependent; examples include SA-516 / ASTM A516 material designations | Not an ASTM A276 stainless-steel option | Fabricated nozzle neck, welded branch, flange, reinforcement pad, or heavy-wall vessel connection | Economical and widely used when corrosion allowance, coating, lining, or process control provides adequate protection. | Magnetic. | Non-corrosive or controlled process service, storage tanks, boilers, and pressure vessels. | ASTM A516 ASTM A105 ASTM A234 ASME Section VIII | Check corrosion allowance, impact-test temperature, weld preheat, post-weld heat treatment, coating or lining, and material compatibility with the vessel shell. |
| Nickel Alloy 625 | N06625 | Not an ASTM A276 stainless-steel grade; normally purchased under nickel-alloy product specifications | Specialized forged or machined nozzle, cladding component, transition piece, or severe-service branch | Nickel-chromium-molybdenum alloy with high resistance to pitting, crevice corrosion, oxidation, and many aggressive chemical environments. | Generally low magnetic response, subject to product condition and cold work. | Seawater, sour service, chemical processing, offshore systems, and high-corrosion applications. | ASTM B564 ASTM B443 ASTM B444 ASME Section VIII | Confirm nickel-alloy specification, weld overlay or cladding procedure, dilution control, PMI, corrosion test requirements, and supply lead time. |