01
Environment
Liquefaction, storage, loading, vaporization, and transfer systems
RTI industry authority
Alloy Piping Components for LNG Systems
LNG systems place unusual emphasis on cryogenic conditions, thermal movement, containment, material toughness, clean documentation, and exact connection data. RTI organizes enquiries for flanges and fittings around the approved process and piping specification, making room for material route, pressure class, facing, bore, inspection, test records, marking, and delivery documentation.
Quick engineering snapshot
Service context before material selection.
These controlled signals help start a technical conversation. Final component and alloy approval stays with the governing project specification and responsible engineering authority.
| Specification | Verified value | Unit |
|---|---|---|
| Environment | Liquefaction, storage, loading, vaporization, and transfer systems | - |
| Corrosion focus | External marine atmosphere, insulation interfaces, condensate, cleaning chemicals, and specific process contaminants should be considered along with cryogenic suitability. | - |
| Temperature consideration | Material, seal, bolting, and component selection must be reviewed against the specified minimum design metal temperature, operating cycle, cool-down, warm-up, and upset conditions. | - |
| Pressure and containment | Containment design requires alignment between piping class, component standard, flange class, facing, gasket system, bore, and approved temperature rating basis. | - |
| Common component route | approved LNG piping class, flange facing, gasket system, and low-temperature design requirement / schedule or bore, weld preparation, fitting type, and thermal-movement allowances | - |
Operating environment
The component is only as well specified as the service around it.
The technical environment map keeps corrosion, temperature, pressure, product details, inspection, and documentation in the same decision path.
Technical environment map
Thermal-service envelope
02
Corrosion
External marine atmosphere, insulation interfaces, condensate, cleaning chemicals, and specific process contaminants should be considered along with cryogenic suitability.
03
Temperature
Material, seal, bolting, and component selection must be reviewed against the specified minimum design metal temperature, operating cycle, cool-down, warm-up, and upset conditions.
04
Pressure
Containment design requires alignment between piping class, component standard, flange class, facing, gasket system, bore, and approved temperature rating basis.
05
Release
Specification, inspection, traceability, and delivery documentation
Corrosion and temperature
Review the mechanism, then confirm the material route.
Corrosion performance changes with the actual medium, temperature, geometry, fabrication, and operating conditions. The alloy name does not replace service-specific engineering review.
Mechanism first
External marine atmosphere, insulation interfaces, condensate, cleaning chemicals, and specific process contaminants should be considered along with cryogenic suitability.
Temperature changes the decision
Material, seal, bolting, and component selection must be reviewed against the specified minimum design metal temperature, operating cycle, cool-down, warm-up, and upset conditions.
Geometry and fabrication matter
Crevices, stagnant zones, weld details, insulation interfaces, gasket selection, and cleaning practice should be reviewed alongside the nominal alloy grade.
Commonly considered alloys
Comparison paths for an informed specification review.
These material pages provide technical information. They are not a substitute for the project material selection process or an approved substitution.
Stainless Steel 316L / UNS S31603
Low-carbon molybdenum-bearing stainless benchmark for controlled process service.
Inconel 625 / UNS N06625
Nickel alloy benchmark for severe corrosion, seawater, and elevated-temperature review.
Super Duplex 2507 / UNS S32750
Super duplex benchmark for chloride-rich and seawater-related applications.
Flanges and pipe fittings
Connection details control the commercial outcome.
For each component, keep material, product-form standard, dimensional standard, pressure class, facing, bore or schedule, testing, and document release separated and clear.
Flanges
Flange selection should confirm approved LNG piping class, flange facing, gasket system, and low-temperature design requirement, pressure class, facing, bore, gasket system, bolting, machining, and any drawing-controlled details before quotation.
Pipe fittings
Elbows, tees, reducers, caps, stub ends, and forged fittings should align schedule or bore, weld preparation, fitting type, and thermal-movement allowances before a purchase order is released.
Material route
Material grade, product-form standard, dimensional standard, inspection plan, marking, packing, and document release are separate controls. They should be written separately in the RFQ.
Relevant standards
Use the right document for the right control.
Product material standard, component dimensional standard, test-certificate route, and project specification each answer a different procurement question.
ASME B16.5 Flange Guide
Flange size, class, facing, and RFQ controls.
ASME B16.9 Fittings Guide
Buttwelding fitting dimensions and procurement controls.
Flange Pressure Classes Explained
Class designation must be reconciled with material and temperature.
EN 10204 3.1 Guide
Manufacturer inspection certificates and release records.
Quality and inspection
Traceability belongs in the RFQ, not at dispatch.
PMI, MTC, EN 10204 3.1, TPI attendance, test records, markings, and release documentation should be aligned with the actual project and ordered product form.
PMI and grade segregation
Define the PMI method, sampling plan, acceptance criteria, and record format when alloy identity is critical to the service or project quality plan.
Material certificates
Request MTC and EN 10204 3.1 documentation when manufacturer-issued inspection records are required, then reconcile heat number, grade, product form, standard, test results, and final marking.
Inspection plan
Build a reviewable dossier with material certificates, traceability, dimensions, marking, inspection points, packing, and any project-specific low-temperature evidence.
Order-specific testing
Testing scope should follow the applicable material and project requirements; the RFQ needs to state any low-temperature, NDE, pressure, or document review requirements explicitly.
Procurement guidance
Build an RFQ an engineer can approve.
A complete enquiry reduces clarification cycles and makes inspection, documentation, packing, and delivery expectations visible from the start.
Design basis
State the fluid or process medium, concentration or contaminants where relevant, design and upset temperatures, design pressure, corrosion allowance, and governing project specification. Final material selection remains an engineering approval.
Commercial scope
Declare the design temperature basis, piping class, flange and fitting details, documents, preservation, dispatch condition, and destination handling instructions.
Document release
Agree document requirements, review points, TPI attendance where required, marking, protective facing covers, packing method, and destination requirements before production release.
No unapproved substitution
Do not treat similar alloy names as interchangeable. Any substitution needs the engineering authority to compare service, product standard, dimensions, tests, and documentation requirements.
Related RTI pathways
Continue the specification review.
Use material data pages, product pages, and engineering guides together when preparing a technical quotation.
Stainless Steel 316L / UNS S31603
Low-carbon molybdenum-bearing stainless benchmark for controlled process service.
Inconel 625 / UNS N06625
Nickel alloy benchmark for severe corrosion, seawater, and elevated-temperature review.
Super Duplex 2507 / UNS S32750
Super duplex benchmark for chloride-rich and seawater-related applications.
Engineering FAQs
Common lng procurement questions.
Answers frame the information that belongs in the RFQ and do not replace formal design review or the project specification.
Structured RFQ
Prepare a cleaner component enquiry
Capture material, standard, dimensions, quantity, inspection, documentation, packing, and destination before the technical quotation is prepared.
Technical quotation
Define your lng component package.
Share the service context, material, product, dimensions, pressure class, facing, testing, documents, destination, and drawing or datasheet details. RTI will use the information to structure the technical quotation pathway.
