Dec 16, 2022

Structural steel for ship hulls

Steel for shipbuilding generally refers to steel for hull structure, which refers to the steel used for manufacturing hull structure produced according to the requirements of classification society construction specification. Often as a special steel order, scheduling, sales, a ship including ship p

At present, several major steel enterprises in China have production and can be produced according to the needs of users of different national specifications for marine steel, such as the United States, Norway, Japan, Germany, France, etc., the specifications are as follows.

Nationality	Specification
China	CCS
United States	ABS
Germany	GL
France	BV
Norway	DNV
Japan	KDK
UK	LR

1. Species specification

Structural steel for the hull is divided into strength levels according to its minimum yield point: general strength structural steel and high strength structural steel.

The general strength structural steel of the CCS standard is divided into A, B, D, E four quality levels; the high strength structural steel of the CCS standard is three strength levels and four quality levels.

A 32	A 36	A 40
D 32	D 36	D 40
E 32	E 36	E 40
F 32	F 36	F 40

2.mechanical properties and chemical composition

General strength hull structural steel mechanical properties and chemical composition:

High strength hull structural steel mechanical properties and chemical composition:

钢材级别	屈服点 σ s (MPa) 不小于	抗拉强度 σ b (MPa)	伸长率 σ% 不小于	碳 C	锰 Mn	硅 Si	硫 S	磷 P
A	235	400-520	22	≤0.21	≥2.5	≤0.5	≤0.035	≤0.035
B				≤0.21	≥0.80	≤0.35
D				≤0.21	≥0.60	≤0.35
E				≤0.18	≥0.70	≤0.35

钢材级别	屈服点 σ s (MPa) 不小于	抗拉强度 σ b (MPa)	伸长率 σ% 不小于	碳 C	锰 Mn	硅 Si	硫 S	磷 P
A 32	315	440-570	22	≤0.18	≥0.9-1.60	≤0.50	≤0.035	≤0.035
D 32
E 32
F 32				≤0.16			≤0.025	≤0.025
A 36	355	490-630	21	≤0.18			≤0.035	≤0.035
D 36
E 36
F 36				≤0.16			≤0.025	≤0.025
A 40	390	510-660	20	≤0.18			≤0.035	≤0.035
D 40
E 40
F 40				≤0.16			≤0.025	≤0.025

3. Note on acceptance of delivery of steel for ships

1.the quality certificate review

Steel delivery must be according to the user’s requirements according to the contract specifications and provide the original quality certificate. Certificate, must have the following content.

(1) specification requirements.

(2) quality record number and certificate number.

(3) furnace batch number, technical grade.

(4) chemical composition and mechanical properties.

(5) Classification society approval certificate and surveyor’s signature.

2. physical examination

Delivery of marine steel, physical objects should be on the production plant logo, etc. Specifically.

(1) classification society approval mark.

(2) the use of paint frame or paste mark, including technical parameters such as furnace batch number, standard grade, length and width dimensions, etc.

(3) the appearance of smooth and smooth, no defects.