Technical steel knowledge, structured for practical use.
123 of 123 articles
A practical map of the common 304/304L/316/316L stainless designations, what the L means, and what buyers should specify beyond the grade shorthand.
Why titanium-stabilized 1.4571/316Ti and low-carbon 316L solve a similar sensitization problem by different metallurgical routes, and why they are not automatic substitutes.
Why Ansteel, Angang Steel, Benxi Steel and Pangang are not interchangeable mill names.
A procurement-focused comparison of the API offshore plate specifications and the EN 10225 offshore structural-steel framework.
Why Annex E and Annex K are not interchangeable UT options: Annex E is the base API 5L NDT framework, while Annex K adds or modifies NDT for sour, offshore and strain-capacity service.
What API 5L Annex J adds for PSL2 pipe ordered for offshore service, how it interacts with Annex K NDT, and what Annex J does not automatically certify.
How API 5L PSL2 grade suffixes identify delivery condition, including the practical distinction between Q&T seamless routes and thermomechanically rolled mother plate/strip used for welded M-grade pipe.
A buyer-focused checklist for ordering API 5L line pipe for offshore service without assuming that base PSL2 automatically covers every offshore requirement.
A practical comparison of API 5L Product Specification Levels 1 and 2, including chemistry, mechanical properties, toughness, NDT, traceability and a correction to a common hydrotest misconception.
A guide to legacy API 5L supplementary-requirement numbers and why SR5, SR6 and especially SR8 should never be interpreted without knowing the API 5L edition.
A procurement-focused comparison of API 5L line pipe and EN 10225 offshore structural tubulars, including scope, manufacturing route, dual certification and dimensional checks.
Why X52 and L360 are corresponding line-pipe strength designations, but should not be treated as a complete material equivalence without checking PSL, edition, delivery condition and supplementary requirements.
A procurement-focused introduction to ASTM A333/A333M Grade 6 low-temperature carbon-steel pipe, including seamless/welded scope, notch toughness and common equivalence mistakes.
A buyer-focused profile of Baosteel, distinguishing the operating producer from China Baowu and summarizing products, pipe capability and certifications.
How Baotou Steel relates to its listed steel producer and why rare-earth businesses are separate.
A visual-reading guide to the core dimensions of I and H sections: overall depth, flange width, web thickness, flange thickness and root radius.
A guide to Bengang, its 2021 restructuring and why it is not the same mill as Angang.
What CEV is, how the common IIW formula is calculated, what it says about weldability and why it should not be used as a universal pass/fail number.
A practical separation of EU construction-product conformity, EN 1090 structural-component conformity assessment and EN 10204 material inspection documents.
Why CEV and Pcm are different weldability indices, how their formulas differ and why the governing standard — not personal preference — decides which one to use.
A practical guide to Charpy V-notch testing: absorbed energy, test temperature, orientation, specimen size, test frequency and why one favourable result cannot be extrapolated to another temperature.
A group-level map of China Baowu and its major operating steel companies, with emphasis on why parent-group ownership does not make all mills interchangeable.
Find the relevant producer profiles by steel product and approval needs.
Understand parent groups, works and the historical company-name traps.
A practical map of the CITIC special-steel platform, its major works, and its distinction from NISCO.
A practical screening checklist for inconsistencies in mill test certificates before technical acceptance.
A reusable method for comparing EN, API, ASTM, ISO, GB, JIS and class-society steel grades without reducing the analysis to yield strength alone.
What Crack Tip Opening Displacement testing measures, how the test is performed, why it differs from Charpy and why offshore qualification programs can contain many separate CTOD results.
How the Daye name, historical Xinyegang identity and the CITIC parent fit together.
Separate the major Delong manufacturing group from similarly named commercial steel suppliers.
How classification-society rules, manufacturer approvals and material certification relate — and why “DNV/ABS approved” is not a steel grade.
How Dongbei Special Steel fits within the Shagang-controlled corporate ecosystem.
What dual or multiple certification actually means, what must overlap, and why a material cannot be re-labelled merely because its chemistry and strength look similar.
How the common 2205 duplex designations relate, why S31803 and S32205 are not just interchangeable labels, and what to check when material is dual-certified.
How EN 10160 plate UT works at a practical level, including the difference between S body classes and E edge classes and what S0/E1 actually means.
A buyer-focused explanation of EN 10204 type 3.1 and 3.2 certificates: who validates them, what specific inspection means and what 3.2 does not automatically guarantee.
A practical map of EN 10204 inspection documents, from declarations of compliance through 3.1 and independently validated 3.2 certificates.
A practical comparison of hot-finished EN 10210 and cold-formed EN 10219 structural hollow sections, including grades, dimensions, section properties and purchasing implications.
A practical map of the five EN 10216 parts for seamless steel tubes for pressure purposes, separated by material family and service-temperature properties.
A direct comparison of the European pressure-tube families: EN 10216 for seamless tubes and EN 10217 for welded tubes, with a map of corresponding service/material families.
A practical map of EN 10217 Parts 1–7 for welded steel tubes for pressure purposes, showing how service temperature, material family and welding route determine the applicable part.
A practical map of the current EN 10225 family for plates, sections and offshore structural hollow sections, including the four-part structure, grade naming and scope limits.
Why EN 10365 and EN 10279 are complementary on channel orders: nominal dimensions/masses versus tolerances on hot-rolled channels.
The welded-versus-seamless EN families for circular steel tubes used in mechanical and general engineering, and how they differ from pressure and structural tube standards.
How coil or strip becomes longitudinally welded pipe by high-frequency resistance/induction welding, and why ERW/HFW/HFI terminology needs context.
Distinguishing the steel group from its specialised listed producer and affiliated works.
A dedicated Fushun profile explaining the Shagang/Dongbei shareholder transition.
A practical explanation of grain-size testing, what it demonstrates and why offshore specifications may require it in addition to ordinary mechanical tests.
How Brinell and Vickers hardness testing differ, how to read HBW/HV results, when cutting a coupon is or is not necessary, and why converted hardness values need caution.
A group-level guide to HBIS and why buyers must distinguish the parent group from specialist operating mills such as Wuyang/Wugang.
A practical comparison of IPE and HEA/HEB/HEM section families, including why nominal size numbers do not mean identical geometry or mass.
Hengyang/Valin names, seamless pipe capabilities and practical certification checks.
How Hold, Witness and Review points work in an ITP, what each means operationally, and why the project-approved ITP always controls the exact obligations.
From steelmaking and beam blanks to universal rolling, cooling, straightening and sawing: a practical overview of hot-rolled section production.
A practical terminology guide to HSS, RHS, SHS and CHS, including why round structural hollow sections should not automatically be treated as pipe.
A buyer-focused map of Hunan Steel and the differences between its plate, flat and pipe operations.
A practical guide to the three variables that are often mixed together in plate Charpy requirements: specimen orientation, test temperature and test frequency.
What ISO/IEC 17025 accreditation actually demonstrates, what an accredited laboratory report does not prove, and how it differs from steel product certification.
Separate the integrated Jiangsu steel producer from similarly named supply-chain websites.
The difference between the Xingcheng manufacturing works, its CITIC parent and sister producers.
Understanding Jianlong as a large multi-site steel group rather than a single mill.
Why the historic VALIN Wuxi Steel identity now appears within a CITIC operating group.
How Jingye’s Chinese production relates to overseas acquisitions and separate legal suppliers.
How Japanese and Chinese H-beam designations differ from European HE/IPE profiles, and how to compare them without inventing a false section equivalent.
Separating the Jiuquan group name from individual carbon and stainless production entities.
How to decode JR, J0, J2 and K2 in European structural steel grades and keep toughness, strength and delivery condition separate.
Why ladle-furnace refining and vacuum degassing are different secondary-metallurgy operations, what each is used for, and why a mill may use both.
An explanation of the historic Laiwu Steel name, today's Shandong Steel/Gangcheng structure and the 2025 transfer of Yinshan Section Steel.
An independent seamless-pipe producer with an oil-and-gas, pressure and structural-tube focus.
A procurement-focused guide to Liuzhou Steel and its wider Guangxi manufacturing ecosystem.
What longitudinal and transverse Charpy orientation mean relative to rolling direction, why results can differ and how to avoid confusing specimen orientation with notch orientation.
A guide to Magang / Maanshan Iron & Steel, its Baowu ownership, common market names and core product families.
How stockholders and service centres can preserve heat-level and piece-level identity when plates, pipes and sections are cut from master material.
What makes ultrasonic testing manual or automated, where PAUT and TOFD fit, and why a technically capable alternative still needs approval when the contract explicitly requires AUT.
A short comparison of conventional martensitic 1.4021 and low-carbon Ni-Mo-alloyed 1.4418, including heat-treatment, corrosion and equivalence cautions.
The practical differences between steel mills, stockholders, distributors and service centres, including inventory, production, certification, cutting and what each supplier type can realistically change.
Why mills impose minimum order quantities, how rolling campaigns drive availability, and how buyers can structure enquiries to reduce lead-time and MOQ problems.
A practical method for converting inconsistent MTO descriptions into a normalized sourcing table without losing line-item identity, technical requirements or quantity traceability.
A practical guide to EN 10025 fine-grain structural steel grades S355N, S355NL, S355M and S355ML, and why they are not the same as S355J2+N.
What NACE MR0175 / ISO 15156 is, how Parts 1–3 are organized, and why sour-service acceptability depends on material condition and environment rather than grade name alone.
A designation-focused comparison of Alloy 600, Alloy 625, C-22 and A-286, including an important distinction: A-286 is an iron-base precipitation-hardening superalloy, not a nickel-base corrosion alloy.
A practical guide to NISCO covering its historical names, CITIC ownership, production scale, product range and international certifications.
What normalizing does to steel, how normalizing rolling can achieve a comparable delivery condition, and why hot-finished does not automatically mean normalized.
Where NORSOK M-001 sits in the specification hierarchy and why it should not be treated as a steel grade or stand-alone product standard.
How to compare required piece lengths with available master lengths, calculate cutting yield and scrap, and preserve technical traceability when sourcing from stock.
Understanding Pangang’s relationship with Ansteel and its specialist material footprint.
What the pitting resistance equivalent number calculates, the common Cr-Mo-N formula and tungsten variant, and why PREN is only a screening index rather than a corrosion guarantee.
Why PWHT is specified, what it can change, which variables must be controlled, and why it must be checked against the material grade, fabrication code and qualified welding procedure.
A site-level profile of Qingdao Special Steel, distinct from the broader CITIC group.
A practical explanation of quenching and tempering, what the Q delivery condition means, and why Q&T steels require care during welding, heat treatment and substitution.
Manufacturing routes for circular, square and rectangular hollow sections, including cold-formed welded, hot-finished welded and seamless products.
A profile of independent Rizhao Steel Holding Group, its scale, ESP/coil and H-section products, and its distinction from Shandong Steel Rizhao.
How one-piece hot-rolled beams differ from plate-built welded beams in geometry, availability, welding, inspection and procurement requirements.
How submerged-arc welded pipe is produced by longitudinal and helical routes, including plate/coil feedstock, forming, welding, expansion and inspection.
A practical process map from solid billet to finished seamless pipe, including piercing, elongation, sizing, heat treatment and inspection.
Group structure, production scale, product families and procurement caveats for Shagang material.
A corporate map separating Shandong Steel Group, listed Shandong Iron & Steel, Laiwu/Gangcheng operations and Shandong Steel Rizhao.
A focused profile of Shandong Steel's Rizhao operation and the critical distinction from the separate Rizhao Steel Holding Group.
A guide to Shougang group identity, operating companies and premium flat-steel products.
What solution annealing does in austenitic and duplex stainless steels, why rapid cooling matters, and how it differs from normalizing, stress relief and quench-and-temper treatment.
A structured pre-acceptance review of a steel PO covering technical scope, document hierarchy, inspection, delivery, marking and commercial risks.
A practical RFQ structure for steel products that separates product identity, technical requirements, inspection, commercial terms and project-specific options.
When to use published kg/m values and when to calculate mass from cross-sectional area, with practical formulas for rolled and fabricated steel sections.
What to check before proposing existing stock for an offshore project that asks for additional testing, traceability or certification.
Why strain-ageing tests are specified for some formed offshore components and what the test is intended to simulate.
A practical introduction to 2507 super duplex, its common UNS/EN designations, corrosion-strength profile and procurement checks.
How TPCO fits into CITIC and why Tianjin Pipe manufacturing certificates must be checked separately.
TISCO’s ownership and the distinction between the group and its listed stainless producer.
How thermomechanical rolling combines deformation, temperature control and cooling to produce fine-grained structural steels with high strength and toughness.
How a stockholder or service centre should preserve the link between cut pieces and the original mill certificate, and what buyers should request before accepting cut stock.
How Tsingshan’s stainless and nickel operations fit together across China and Indonesia.
How British UB/UC, American W-shapes and European HE/IPE profiles differ, and why cross-series substitution should be exceptional and designer-approved.
A product-form map for choosing the right UT reference for plate, beams, bars and steel tubes instead of applying one ultrasonic standard to every steel product.
A practical comparison of ultrasonic and radiographic testing: what each method sees well, where each has limitations, and why one cannot automatically replace the other.
A decision guide for selecting among six commonly confused European tube and hollow-section standard families by application first, then manufacturing route.
An introductory map of China’s steel groups and the mills beneath them.
The practical difference between a Welding Procedure Specification and the qualification record behind it, including pWPS, WPQR/PQR and welder qualification.
A buyer-focused profile of Wuyang/Wugang, HBIS's specialist wide and heavy plate producer, including offshore/API product ranges and class approvals.
A focused profile of Xianggang, its Hunan Steel relationship and heavy-plate sourcing considerations.
Identifying Xinyu (XISCO) within Baowu without confusing it with Baosteel.
How Youfa differs from primary steel producers and seamless-pipe mills.
Why offshore specifications frequently require Z25 or Z35, what through-thickness ductility measures, and how it differs from ultrasonic testing.
A guide to the Zhongtian/Zenith name and multiple manufacturing bases.