Q345R
Data verifiedQ345R is China’s standard pressure-vessel plate to GB/T 713 — the R (容， vessel) variant of the Q345 family with tighter sulfur, phosphorus and inspection requirements. It is the default domestic grade for GB 150 coded vessels and the usual Chinese offer against A516 Gr.70.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.20 |
| Si | 0.15–0.40 |
| Mn | 1.20–1.60 |
| P | ≤0.025 |
| S | ≤0.015 |
| Al | ≥0.020 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Yield strength | ≥345 MPa (≤16 mm) |
| Tensile strength | 510–640 MPa |
| Density | 7.85 g/cm³ |
Heat treatment
Supplied normalized (standard for vessel plate); impact tested at 0 °C per GB/T 713.
Equivalent grades
| Standard | Designation |
|---|---|
| din | P355GH (near) |
| aisi | A516 Gr.70 (near) |
| gb | Q345R (GB/T 713) |
Compare side by side: Q345R vs A516 Gr.70 · Q345R vs P355GH
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Pressure vessels, storage spheres, towers, heat exchangers under GB 150 / TSG rules.
Processing: Excellent weldability; normalizing after forming and PWHT follow GB 150 fabrication requirements.
FAQ
- Q345R vs Q345B plate?
- Same strength class, different specification: Q345R (GB/T 713) is vessel quality — tighter P/S limits, mandatory impact and ultrasonic testing options. Never substitute structural Q345B/Q355B on coded vessels.
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Ask for a quotationVisit NasteelSource: GB/T 713 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.