One Family, Four Names
Carbon and low-alloy boiler tubes travel under four standard families depending on where the plant was engineered: EN 10216-2 (Europe, seamless), DIN 17175 (the German classic that EN 10216-2 superseded — still specified on thousands of running plants), GB/T 5310 (China, seamless high-pressure boiler tube, current edition 2023) and the ASME family (SA106/SA192/SA210/SA213) covered in our alloy boiler tube guide. This article maps them onto each other so a European-spec inquiry can be quoted from a Chinese mill without losing meaning.
Scope: What “High-Pressure Boiler Tube” Means
GB/T 5310 covers seamless tubes for high-pressure boilers — water-wall, superheater, reheater and economizer circuits, typically working above 9.8 MPa with metal temperatures from about 450 °C (carbon steels) up to 650 °C (the 9–12%Cr grades). EN 10216-2 covers the same pressure-tube duty in elevated-temperature execution. Both require heat treatment per grade, 100% NDT, and hydrostatic or equivalent pressure testing — these are certified pressure-retaining tubes, not structural tube.
Grade-by-Grade Cross Reference
| Family | Carbon | C-Mn | 0.3Mo | 1Cr-0.5Mo | 2.25Cr-1Mo |
|---|---|---|---|---|---|
| EN 10216-2 | P235GH / P265GH | 16Mo3¹ | — | 13CrMo4-5 | 10CrMo9-10 |
| DIN 17175 | St35.8 / St45.8 | 17Mn4 / 19Mn5 | 15Mo3 | 13CrMo44 | 10CrMo910 |
| GB/T 5310 | 20G | 20MnG / 25MnG | 15MoG | 15CrMoG | 12Cr2MoG |
| ASME | SA106 B / SA192 | SA210 A-1/C | — | SA213 T11 / SA335 P11 | SA213 T22 / SA335 P22 |
¹ 16Mo3 is the EN 0.3Mo grade; DIN’s 15Mo3 is its predecessor designation.
Workhorse Mechanical Requirements
| Grade | Min Yield (MPa) | Tensile (MPa) | Min Elongation (%) | Typical Metal Temp Limit |
|---|---|---|---|---|
| 20G (GB/T 5310) | 245 | 410–550 | 24 | ≈ 450 °C heating surfaces |
| P265GH (EN 10216-2) | 265 | 410–530 | ≈ 21–23 (by size) | ≈ 450 °C |
| St45.8 (DIN 17175) | 245 | 410–530 | ≈ 21+ | ≈ 450 °C |
| 16Mo3 / 15MoG | 275 | 450–600 | ≈ 22 | ≈ 500 °C |
| 13CrMo4-5 / 15CrMoG | 290 | 440–590 | ≈ 22 | ≈ 540 °C |
Yield values are the small-size baselines; both EN and GB reduce required yield as wall/section grows. Always quote allowable stress from the governing design code at design temperature — never from this room-temperature table.
Manufacturing, Heat Treatment and Delivery
All four families supply hot-rolled (hot-finished) and cold-drawn tubes, delivered heat-treated: carbon and Mo grades normalized (20G, P265GH, St45.8, 16Mo3), Cr-Mo grades normalized plus tempered. GB/T 5310 offers dimensional tolerance classes D1–D4 for OD (from ±1.5% down to ±0.5%) — the class must be selected on the PO. Chemical analysis is heat-based with product re-check allowances; every length gets hydrostatic pressure testing or equivalent 100% NDT (UT/eddy current), plus flattening, flaring and (for thicker walls) bend tests per the standard’s tables.
What the Mill Certificate Must Show
A compliant EN 10204 3.1 certificate for this family lists: heat and product chemistry, tensile at room temperature, the full heat-treatment record (normalizing/tempering temperatures — for the Cr-Mo grades this is a life-limiting parameter, not paperwork), hardness where specified, NDT scope and result, hydro or NDE substitution statement, and traceability from certificate line to stencilled tube. For replacement jobs on running plants, match the old certificate’s heat-treatment condition — same grade name in the wrong condition can creep in service.
Substitution between the four families is an engineering decision, not a trader’s: compare allowable stress at design temperature under the governing code (EN 13445/12952 vs ASME I), then get written approval from the engineer of record.
Frequently Asked Questions
Is DIN 17175 still valid for new orders?
EN 10216-2 superseded it, but plants built to DIN keep specifying St45.8/13CrMo44 for replacements. Most Chinese mills quote EN 10216-2 equivalents with the DIN designation cross-referenced on the MTC — acceptable when the engineer approves the mapping.
Why do 20G and St45.8 look identical in the table?
They are the same job described by two systems: 0.17–0.24% C carbon steel, 245/410–530 mechanicals, normalized delivery. Differences sit in tolerance philosophy, test categories and certificate format — not in the steel.
Can GB/T 5310 tubes replace A192/A210 on an ASME-coded boiler?
Only through the code case/ substitution route with the boiler engineer’s approval. ASME-coded construction expects ASME-material certificates; GB/T 5310 on a non-code industrial boiler is, however, routine.
What NDT comes standard?
Each length is UT or eddy-current tested per the standard’s acceptance classes, plus hydro. For superheater-grade replacement tube, buyers commonly add full-length UT to a stricter reference level — name it in the PO.
CREATEEL supplies boiler tubes across EN 10216-2, DIN 17175 designations, GB/T 5310 and ASME SA families — 3.1 certified, heat-treatment records included, third-party inspection welcomed.
Standards & references: EN 10216-2 · GB/T 5310
Need help choosing between standards? CREATEEL exports carbon steel welded and seamless pipe to GB, EN, BS, ASTM and API standards every week, with EN 10204 3.1/3.2 certification. Send us your specification and we will map it to the right standard.
