ТЕГИ ГОРЯЧЕГО БЛОГА
EN 10255
EN 10255:2015 – Non-Alloy Steel Tubes Suitable for Welding, Threading and Other Joining Methods
1. Стандартное определение и предпосылки
EN 10255 is a European standard that has been approved by CEN. The current version of EN 10255:2015 replaces the previous editions (2004, 2007). It applies to non-alloy steel tubes for fluid purposes in general. The specification promotes consumer safety, product quality and compatibility by providing production and testing protocols suitable for manufacturers, installers, service providers, and users.
Key features:
Applies to seamless and welded tubes with tapered threads (taper 1 : 16) according to EN 10226-1.
Material name:
S195T (S = structural steel 195 = minimum yield strength in N/mm2 T = steel for tubes) PPMaterial designator: S195T (S = Baustahl, 195 = min. in MPa, T = tube application)1.0026 steel according to the EN 10020 non-alloy steel
2. Область применения
2.1 Основные области применения
Fluid Transport: Water, gas, steam in low-pressure systems (design pressure ≤4.0 MPa)
Structural Components: Non-load-bearing elements (e.g., building supports, machinery frames)
Connection Compatibility: Designed for welding, threading, and socket joints
2.2 Service Limitations
Диапазон температур: -30°C to 120°C (conventional media); higher temperatures require additional assessment
Environmental Conditions: Suitable for neutral soils (pH 4-10); corrosive environments mandate zinc coating or epoxy protection (EN 10240)
3. Размеры и допуски
3.1 Диапазоны размеров
| Параметр | Диапазон | Series |
| Наружный диаметр | 10.2 mm – 165.1 mm | Medium Series |
| (Thread Size) | (1/8″ to 6″) | Heavy Series |
| Толщина стенок | Defined by agreement | Three specified types |
3.2 Основные допуски
Table: Geometric Tolerances (EN 10255:2015)
| Параметр | Допустимое отклонение | Стандарт испытаний |
| Наружный диаметр | ±0.75% OD (DN < 508 mm) | EN 10233 (flattening) |
| Толщина стенок | ±12.5% t (Light) / ±10% t (Heavy) | Ultrasonic/Eddy Current |
| Овальность торца трубы | ≤1% OD (в пределах 100 мм от конца) | Измерение штангенциркулем |
| Прямолинейность | ≤0.2% of tube length | Straightedge method |
Note: Tube ends require 100-150 mm uncoated zone for welding (bevel angle ≤30°).
4. Требования к материалам и характеристикам
4.1 Chemical Composition
*S195T Non-Alloy Steel Limits (wt%)*:
Carbon (C) ≤ 0.24%
Sulfur (S) ≤ 0.035%
Phosphorus (P) ≤ 0.035%
Manganese (Mn) ≤ 1.40%
4.2 Механические свойства
Table: Mechanical Requirements for S195T
| Недвижимость | Требование | Стандарт испытаний |
| Yield Strength (ReL) | ≥195 MPa | EN 10002-1 |
| Tensile Strength (Rm) | 330–500 MPa | |
| Elongation (A) | ≥25% (5.65√S₀ gauge) | |
| Yield-to-Tensile Ratio | ≤0.93 |
5. Manufacturing and Testing Requirements
5.1 Обязательные испытания
Испытание давлением:
Hydrostatic/pneumatic at ≥1.5× working pressure (duration ≥5 s)
Alternative: Electromagnetic testing (EN 10246-1) for DN<600 mm tubes
Mechanical Tests:
Tensile and flattening tests (2 samples per ≤100-tube batch per EN 10233)
5.2 Неразрушающий контроль (NDE)
Контроль сварных швов: 100% UT or RT for welded tubes (RT acceptance: EN ISO 11666 Level II)
Дефекты поверхности: Repair/cut out if depth >12.5% wall thickness
6. Certification and Compliance
6.1 CE/UKCA Certification
Module 3: Notified Body (e.g., NB 1020) audits + sample testing (5-year validity)
Module 4: Manufacturer self-verification + Declaration of Performance (DoP) + FPC system
6.2 Key Certification Items
Reaction to fire performance
Dimensional tolerance verification
Hazardous substance testing (RoHS compliance)
7. Technical Evolution and Industry Impact
7.1 Routine Maintenance (2015)
Further compatible with other joining processes (push-fit etc.)
Explicit hazardous substance limits (Pb, Cd, Hg, Cr+6, PBB, PBDE)
Closer foreign equivalent would be S195T and also look for Gr B with CHEMICALS 9370 0.10/0.20 S195T 390102045 S195T 8159 (TS-14) 0.02/0.22 A 34020 12 0.025 0.015 22 C–C 410 QVERIFY Read it and weep.
7.2 Engineering Value
4、Economicaly cut:Reducing the cost of material by 30% by optimized the series of Medium/ Heavy.
1>Safety Ensured: Yield-to-tensile ratio cap (<=0.93) makes sure no failure occurs below the yield strength.
8. Conclusion and Technical Trends
EN 10255 establishes the benchmark for European low-pressure fluid conveyance systems through:
Precise dimensional control
Non-alloy steel performance grading
Connection versatility
Future Focus:
Sustainable low-carbon steel variants (e.g., S195T-L)
Automated UT inspection (EN ISO 10893-11)
Руководство по внедрению:
Gas pipelines: Prefer Heavy series + zinc coating (EN 10240)
EU exports: Specify CE certification module (3 or 4) in contracts
