Shipbuilding Steel Pipe Application
Competition in the shipbuilding market is getting fiercer each day and a lot of companies scrambled to produce larger quantities of shipbuilding pipes required. But, it is not the quantity that matters, rather the quality. Because of the environment in which the pipes are utilized, the pipes are asked of high-resistance to corrosion. As a result, high-quality, and long-endurance pipes are being specified.
Main Grade of Shipbuilding Steel Pipe
320, 360, 410, 460, 490
Pipe for Ship-building（GB5213-85）: Carbon steel seamless pipe which is used for Level 1& Level 2 pressure pipe. The working temperature of the pipe wall to the seamless pipe can not over 450℃, but the working temperature of the pipe wall to alloy steel seamless pipe can over 450℃.
Pipe for Ship-building (GB5312-1999): Carbon Steel and Carbon-manganese Steel Seamless Pipes for Ship-building is mainly is used for Level 1& Level 2 pressure pipe. The standard materials are Grade 360,410,460 etc.
Shipbuilding Steel Pipe Standard：With Classification Society Quality Authentication from LR, ABS, NK, GL, DNV, BV, KR, RINA, CCS
Shipbuilding Steel Pipe Dimensional Tolerance:
| Types of steel tubes | Outer diameters | wall thickness | ||
| Cold-rolled tubes | Tube size(mm) | tolerances | Tube sizes | Tolerances |
| (mm) | (mm) | (mm) | ||
| ＞30～50 | ±0.3 | ≤30 | ±10％ | |
| ＞50～219 | ±0.8％ | |||
| Hot-rolled tubes | ＞219 | ±1.0％ | ＞20 | ±10％ |
Shipbuilding Steel Pipe Mechanical Property :
| Standard code | Grade | Tensile strength（MPa） | Yield strength（MPa） | Elongation（％） |
| GB/T5312 | 320 | 320～410 | ≥195 | ≥25 |
| 360 | 360～480 | ≥215 | ≥24 | |
| 410 | 410～530 | ≥235 | ≥22 | |
| 460 | 460～580 | ≥265 | ≥21 | |
| 490 | 490～610 | ≥285 | ≥21 |
Shipbuilding Steel Pipe Chemical Composition:
| Standard code | Grade | Tensile strength（MPa） | Yield strength（MPa） | Elongation（％） |
| GB/T5312 | 320 | 320～410 | ≥195 | ≥25 |
| 360 | 360～480 | ≥215 | ≥24 | |
| 410 | 410～530 | ≥235 | ≥22 | |
| 460 | 460～580 | ≥265 | ≥21 | |
| 490 | 490～610 | ≥285 | ≥21 |
Seamless Steel Tube and Pipe for Ship Building Usage
| Society | Standard or usage | Steel grade | chemical composition, % | |||||||||||
| C | Si | Mn | P | S | Cr | Ni | Cu | Al | Mo | V | P+S | |||
| GLR | Non alloly | GL-R 410 | ≤ | ≤ | ≤ | ≤ | ≤ | – | – | – | ≥0.020 | – | – | – |
| 0.21 | 0.35 | 1.4 | 0.025 | 0.02 | ||||||||||
| GB 18248 | 37Mn | 0.34 | 0.1 | 1.35 | ≤ | ≤ | ≤ | ≤ | ≤ | – | – | – | ≤ | |
| ~0.40 | ~0.30 | ~1.65 | 0.03 | 0.03 | 0.3 | 0.3 | 0.2 | 0.055 | ||||||
| EN 10297 | 34CrMo4 | 0.3 | ≤ | 0.6 | ≤ | ≤ | 0.9 | – | – | – | 0.15 | – | – | |
| ~0.37 | 0.4 | ~0.90 | 0.035 | 0.035 | ~1.20 | ~0.30 | ||||||||
| DNV | for pressure ASTM A53/A53M | A53B | ≤ | – | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | – | ≤ | ≤ | – |
| 0.3 | 1.2 | 0.05 | 0.045 | 0.4 | 0.4 | 0.4 | 0.15 | 0.08 | ||||||
| ABS | for pressure | Grade 3 | ≤ | – | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | – | ≤ | ≤ | – |
| 0.3 | 1.2 | 0.05 | 0.045 | 0.4 | 0.4 | 0.4 | 0.15 | 0.08 | ||||||
| BV | for pressure | 410HB | ≤ | ≤ | 0.4 | ≤ | ≤ | – | – | – | – | – | – | – |
| 0.21 | 0.35 | ~1.20 | 0.04 | 0.04 | ||||||||||
| LR | for pressure | 410 | ≤ | ≤ | 0.4 | ≤ | ≤ | ≤ | ≤ | ≤ | – | ≤ | – | – |
| 0.21 | 0.35 | ~1.20 | 0.045 | 0.045 | 0.25 | 0.3 | 0.3 | 0.1 | ||||||
| KR | for pressure | RST138 | ≤ | ≤ | 0.3 | ≤ | ≤ | – | – | – | – | – | – | – |
| 0.25 | 0.35 | ~0.90 | 0.04 | 0.04 | ||||||||||
| RST142 | ≤ | 0.3 | ≤ | ≤ | – | – | – | – | – | – | – | |||
| 0.3 | ~1.00 | 0.04 | 0.04 | |||||||||||
| RST238 | ≤ | 0.1 | 0.3 | ≤ | ≤ | – | – | – | – | – | – | – | ||
| 0.25 | ~0.35 | ~1.10 | 0.035 | 0.035 | ||||||||||
| RST242 | ≤ | 0.3 | – | – | – | – | – | – | – | |||||
| 0.3 | ~1.40 | |||||||||||||
| RST249 | ≤ | 0.3 | – | – | – | – | – | – | – | |||||
| 0.33 | ~1.50 | |||||||||||||
| RST338 | ≤ | 0.3 | – | – | – | – | – | – | – | |||||
| 0.25 | ~0.90 | |||||||||||||
| RST342 | ≤ | 0.3 | – | – | – | – | – | – | – | |||||
| 0.3 | ~1.00 | |||||||||||||
| NK | for pressure | grade 1 No3/ KSTPG 42 | ≤ | ≤ | 0.3 | ≤ | ≤ | – | – | – | – | – | – | – |
| 0.3 | 0.35 | ~1.00 | 0.04 | 0.04 | ||||||||||
| CCS | for pressure | 360 | ≤ | ≤ | 0.4 | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | |||
| 0.17 | 0.35 | ~0.80 | 0.04 | 0.04 | 0.25 | 0.3 | 0.3 | 0.1 | ||||||
| 410 | ≤ | ≤ | 0.4 | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | |||||
| 0.21 | 0.35 | ~1.20 | 0.04 | 0.04 | 0.25 | 0.3 | 0.3 | 0.1 | ||||||
| 460 | ≤ | ≤ | 0.8 | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | |||||
| 0.22 | 0.35 | ~1.40 | 0.04 | 0.04 | 0.25 | 0.3 | 0.3 | 0.1 | ||||||
| 490 | ≤ | ≤ | 0.8 | ≤ | ≤ | ≤ | ≤ | ≤ | ≤ | |||||
| 0.23 | 0.35 | ~1.50 | 0.04 | 0.04 | 0.25 | 0.3 | 0.3 | 0.1 | ||||||
