Air Separation Unit Forgings — Cryogenic Valve Body, Flange & Cold Box Piping Component Forgings for Industrial Gas Plants
Shivam Forge manufactures cryogenic-grade forgings for air separation units (ASUs) — the industrial gas plants that distill atmospheric air into oxygen, nitrogen, and argon — including valve body and flange forgings in 304L/316L stainless steel and 9% nickel steel for cold box service down to approximately −196°C, alongside carbon steel forgings for ambient-temperature balance-of-plant systems. Rajkot, India. Call +91-9265772827.
Air separation units produce industrial gases — primarily oxygen, nitrogen, and argon — by cooling atmospheric air down to cryogenic temperature until it liquefies, then separating the liquefied air into its component gases through fractional distillation, exploiting the fact that oxygen, nitrogen, and argon each boil at a distinct temperature. This process requires cooling air to approximately −196°C, the boiling point of nitrogen at atmospheric pressure, and often colder still depending on the specific separation and purity requirements involved — placing the ASU's cold box (the insulated enclosure housing the cryogenic distillation columns, heat exchangers, and associated cryogenic piping) among the coldest sustained-temperature industrial process environments found in any manufacturing or process industry. Every valve, flange, and piping component within the cold box and its immediately connected cryogenic piping must be manufactured from a material qualified for reliable service at this temperature, since standard carbon steel — perfectly suitable for the ASU's ambient-temperature balance-of-plant systems elsewhere in the facility, including compression, ambient piping, and utility systems — undergoes a ductile-to-brittle transition at cryogenic temperature and would be entirely unsuitable and genuinely dangerous if specified for cold box service. Austenitic stainless steels (304L and 316L), which retain ductility and impact toughness at cryogenic temperature due to their face-centred-cubic crystal structure, dominate ASU cold box valve and flange material specification, while 9% nickel steel, the historic standard cryogenic material for LNG service, sees some ASU application as well particularly for larger structural cryogenic piping. Given that ASUs typically operate continuously for extended periods to support the industrial gas supply contracts and downstream processes (steelmaking, chemical processing, healthcare oxygen supply, and general industrial gas markets) that depend on reliable gas output, cold box component material qualification and reliability carry genuine consequence for plant uptime and, given the safety implications of cryogenic material failure, for personnel safety as well.
Forged valve body components for cryogenic distillation column and cold box piping isolation, control, and safety relief applications, in 304L or 316L stainless steel engineered for reliable sealing and mechanical integrity at cold box operating temperature.
Forged flanges in 304L/316L stainless steel or 9% nickel steel for cryogenic piping connections within and immediately connected to the cold box, supporting the distillation column, heat exchanger, and cryogenic liquid product piping systems.
Forged flange and valve components for cryogenic liquid product storage tank piping and transfer systems, supporting reliable containment and transfer of liquid oxygen, nitrogen, and argon downstream of the primary cold box separation process.
Standard carbon and alloy steel forgings for ambient-temperature compression, balance-of-plant piping, and utility systems throughout the ASU facility that do not experience direct cryogenic exposure.
Charpy V-notch impact testing at cryogenic test temperature verifying material toughness meets the ductile fracture behaviour ASU cold box service requires, with results documented as part of material certification for cold box component qualification.
Forged flanges and valve bodies manufactured to support ASME B16.5 (flanges) and B16.34 (valves) dimensional and pressure-temperature rating compliance, with material qualification aligned to cryogenic industrial gas service requirements.
Material test certificates per EN 10204 3.1 as standard, with 3.2 third-party witnessed certification available, including full Charpy impact test result documentation for cryogenic service material qualification records.
Full batch-to-billet material traceability supporting the rigorous documentation standards ASU EPC contractors and industrial gas plant operators require for safety-critical cryogenic service components.
Air separation units occupy a distinctive position among industrial gas and process facilities: producing oxygen, nitrogen, and argon by distilling liquefied atmospheric air requires cooling that air to cryogenic temperature — approximately −196°C, nitrogen's boiling point at atmospheric pressure, and colder still for some separation stages — making the ASU cold box one of the coldest sustained-temperature process environments found anywhere in industrial manufacturing. This extreme temperature requirement is not incidental to the process; it's the entire mechanism by which fractional distillation separates air into its component gases, since oxygen, nitrogen, and argon each condense and boil at distinct temperatures close together, and achieving clean separation between them depends on precise, sustained cryogenic temperature control throughout the distillation columns and associated heat exchangers housed within the cold box.
This temperature requirement drives ASU cold box material specification directly. Standard carbon steel, entirely appropriate and economical for ambient-temperature process equipment, undergoes a ductile-to-brittle transition at low temperature — a change in fracture behaviour that makes it susceptible to sudden, catastrophic brittle fracture under conditions that would produce only safe, gradual deformation at room temperature. This makes carbon steel entirely unsuitable, and genuinely dangerous, for any valve, flange, or piping component within the cold box or in direct contact with cryogenic process fluid. Austenitic stainless steels — 304L and 316L in particular — dominate cold box material specification instead, since their face-centred-cubic crystal structure does not exhibit the same pronounced low-temperature embrittlement that carbon and many low-alloy steels show, allowing these grades to retain adequate ductility and impact toughness reliably down to cryogenic temperature. 9% nickel steel, familiar from LNG cryogenic service, also sees application in ASU cryogenic piping, particularly for larger structural piping runs where its cost profile relative to fully austenitic stainless can be advantageous at scale.
Beyond the cold box itself, an ASU facility includes substantial ambient-temperature balance-of-plant equipment — air compression systems, ambient piping, and general utility systems — that operate at ordinary industrial temperature and are appropriately specified in standard carbon or alloy steel, meaning a complete ASU forged component supply picture spans both the specialized cryogenic-grade requirements of the cold box and cryogenic liquid product systems, and the more conventional material requirements of everything else in the plant. What ties the two together operationally is the premium placed on component reliability: ASUs typically run continuously over extended periods to meet the industrial gas supply contracts and downstream processes — steelmaking, chemical processing, healthcare oxygen, and broader industrial gas markets — that depend on their output, meaning any cold box component failure carries genuine operational and safety consequence disproportionate to what an equivalent failure in a less continuously critical process system would represent.
For ASU EPC contractors, industrial gas plant operators, and equipment manufacturers sourcing cryogenic-qualified forged valve bodies, flanges, or piping components for air separation unit cold box service, Shivam Forge provides Charpy impact-tested material in 304L/316L stainless steel and 9% nickel steel with full EN 10204 3.1/3.2 documentation, alongside standard carbon steel forgings for ambient-temperature balance-of-plant systems. Contact our engineering team at +91-9265772827 or sales@shivamforge.com with your drawing and cryogenic service specification for a manufacturability review and quotation.
Air separation units cool atmospheric air to approximately −196°C to liquefy it and separate it into oxygen, nitrogen, and argon through fractional distillation, exploiting each gas's distinct boiling point. At this temperature, standard carbon steel undergoes a ductile-to-brittle transition and becomes susceptible to sudden, brittle fracture, making cryogenic-qualified materials mandatory for any cold box component in direct contact with cryogenic process fluid.
304L and 316L austenitic stainless steel are the standard materials for ASU cold box valve bodies and flanges, since their face-centred-cubic crystal structure retains ductility and toughness at cryogenic temperature. 9% nickel steel, the historic LNG cryogenic standard, also sees application in some ASU cryogenic piping, particularly larger structural piping runs.
No. Only components within the cold box and immediately connected cryogenic piping and cryogenic liquid product systems require cryogenic-qualified material. Ambient-temperature balance-of-plant systems elsewhere in the facility — compression equipment, ambient piping, and general utility systems — are appropriately specified in standard carbon or alloy steel.
Air separation units typically operate continuously over extended periods to support the industrial gas supply contracts and downstream processes that depend on reliable gas output, meaning cold box component failure represents a genuinely serious operational and, given cryogenic material failure's safety implications, safety event — placing a premium on material qualification and manufacturing quality established at the sourcing stage.
Yes. Charpy V-notch impact testing at cryogenic test temperature is performed and documented as part of material certification for cold box valve, flange, and piping components, verifying the ductile fracture behaviour ASU cryogenic service requires.
Why Choose Shivam Forge
Shivam Forge delivers precision hot-forged components from our integrated Shapar, Rajkot facility — covering forging, CNC machining, heat treatment, and quality inspection under one roof.
