High Strength Steel AH36 Plate SIZE : 50mmT x 2438mmW x 1500mmL
Ship Steel Plate CCS LR BV Class For Marine
Shipbuilding steel plate refers to the carbon and alloy steel plate
used in offshore and marine contructions, common grades are A, B,
D, E, AH32/36/40, DH32/36/40, and EH32/36/40 which ranged from
different strength. The plates usually used to manufacture ship
hulls, bulkheads, upper decks and hatch covers for tankers, bulk
carriers, container ships and LNG carriers.
AH36, DH36, EH36 Steel - Common Use High Strength Steel in Offshore
& Marine
For the high strength shipbuilding plates like AH36, DH36, EH36
steel plate, they have been widely used in high stress areas of
ships, comparing with general strength steel, they are offering the
same strength with the smaller thickness.
Materials
Shipbuilding steel material in carbon and alloy steel, compatible
with high strength, low temperature and high heat input soldering.
Shipbuiding Standards from Different Countries
Shipbuilding steel plates are produced under the approval of
production methods of classification societies in different
countries refers to offshore and marine steels.
- ABS (American Bureau of Shipping)
- BV (Bureau Veritas)
- CCS (China Classification Society)
- DNV (Det Norske Veritas)
- GL (Germanischer Lloyd)
- HR (Hellenic Register of Shipping)
- KR (Korean Register of Shipping)
- LR (Lloyd's Register of Shipping)
- NK (Nippon Kaiji Kyokai)
- RINA (Registro Italiano Navale)
- RS (India Register of Shipping)
Grades: A, B, D, E, AH32/36/40, DH32/36/40, EH32/36/40
According to its yield strength, shipbuilding plate of can be
divided into below grades:
- Grade A steel is the impact force subjected to normal temperature
(20 ° C).
- Grade B steel impact force at 0 °C.
- Grade D steel impact force at -20 °C.
- Grade E steel impact force at -40 °C.
- High-strength shipbuilding steel plate can be further divided into:
AH32, DH32, EH32; AH36, DH36, EH36 and AH40, DH40, EH40.
1. The general grades A, B, D, and E are distinguished according to
the impact temperature of the steel. The impact values of all
grades of steel are the same.
2. High-intensity hull structure steel preheating requirements: For
all AH, DH, EH plate thickness greater than 30mm angle, butt
joints, shall be preheating to 120 ~ 150 °C before welding.
3. For thickness of the plate ≤ 30mm, the ambient temperature is
below 5 ° C, preheated to 75 ° C; Ambient temperature below 0 ° C,
preheated to 75 ~ 100 ° C.
Dimensions Range
Thickness Range: 5 mm -150 mm
Width Range: 1500 mm - 3900 mm
Length Range: 6 m, 12 m, coils
Surface Treatment
With anti-rust painting.
Chemical and Mechanical Requirements
C (carbon) is an indispensable strengthening element in steel, but
the increase in C content reduces the low-temperature impact
toughness of steel and deteriorates the weldability of steel.
Therefore, it is necessary to control the C content in the steel.
According to the experience of producing aluminsum-containing
steel, in order to ensure the aluminum content in the steel and the
fluidity of the molten steel, the method of pre-deoxidation is
strictly to control the carbon content of the end point and the
alloying of the large-pack alloy to control the oxidation of the
molten steel. The way of adding aluminum.
In order to ensure good low temperature impact toughness of the
steel grade, the rolling of the 355MPa class ship plate adopts a
strict type II controlled rolling process.
|
|---|
| | | | | |
| Average impact absorption workAkv/J |
| |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
Processing for Different Grades
Grade A and B
The general strength of grade A and B shipbuilding steel plates can
meet the requirements of process and mechanical properties through
ordinary rolling, so the production process is relatively simple.
Grade D, E (DH32, DH36, EH 32, EH 36)
Grade D and E series (inlcuding AH32/36, DH32, DH36, EH32, EH36)
shipbuilding steel plates require good low temperature toughness
and good welding performance. The production high-strength
shipbuilding steel plate needs to be normalized by means of
controlled rolling and controlled cooling or heat treatment
processes with more complete equipment. At the same time, the
internal steel purity of the supplied billets is required to be
high, especially the content of S, P, N, 0 and H in the steel
should be strictly controlled.
Alloy Elements Added to Improve Toughness
In order to ensure the performance of high-strength ship plates,
micro-alloying technology is adopted. By adding Nb, V, Ti and other
alloying elements to the steel, combined with the controlled
rolling process, the grain is refined and the toughness is
improved.
Direction of Development for Shipbuilding Plate
High strength, high specification, with the ship's large-scale and
ety, and changes in coating specifications, the demand for ordinary
A-class panels is gradually reduced, and the demand for
high-strength panels is increasing, which is concentrated in large
ships of 5m wide. Plate, 200-300mm thickness special thick ship
board.
