1. Basic Definition
S235JRH is a structural steel according to the European standards (EN 10219/EN 10210), a low-alloy hot-rolled steel, mainly used for the manufacture of high-frequency welded pipes and straight-seam welded pipes, with high yield strength and good impact toughness. It has high yield strength and good impact toughness.
2. Naming rules and performance indexes
Naming meaning:
S: stands for 'structural steel' (Structural Steel);
235: indicates that the minimum yield strength of 235MPa;
JRH: identifies its specific heat treatment process, with high low-temperature impact toughness (usually adapted to harsh environments).
Mechanical properties:
Yield strength: ≥235MPa;
Tensile strength: 360-510MPa;
Elongation: ≥ 18% (reflecting the material ductility).
3.the chemical composition
The chemical composition of S235JRH complies with the following range (mass percentage):
Carbon (C): ≤ 0.17%;
Silicon (Si): ≤ 0.35%;
Manganese (Mn): ≤ 1.60%;
Phosphorus (P), sulfur (S): ≤ 0.035%.
Through strict elemental control, it ensures welding performance and corrosion resistance.
4.Applications
Pipeline engineering:
High-frequency welded pipe and straight seam welded pipe, suitable for oil and gas transmission, water conservancy engineering and other scenes.
Building structure:
Load-bearing components such as bridge supports and building frames, utilising their high strength and toughness.
Mechanical Manufacturing:
Vehicle chassis, engineering machinery components and other areas that need to withstand dynamic loads.
5. Differences with other European standard steels
Comparison with S235JR:
S235JRH emphasises higher impact toughness (marked by the 'H'), whereas S235JR is a general grade structural steel, suitable for general welding requirements.
Comparison with Q235B:
S235JRH is equivalent to European Standard Q235B, but the latter is subject to the Chinese standard (GB/T 700), with slightly different elemental control.
6. the implementation of standards and processing requirements
Standard basis: EN 10219 (cold-formed welded hollow sections), EN 10210 (hot-formed welded structural sections).
Delivery status: usually supplied in hot rolled or controlled rolled condition, can be directly used for welding or cold processing.
Summary
S235JRH is a low alloy, high toughness structural steel designed for welded pipes and load bearing structures, with the advantages of high yield strength, good low temperature impact toughness and stable weldability.
