LR DH69 steel plate - Knowledge

LR DH69 shipbuilding steel plate is a crucial material for the maritime industry, offering excellent mechanical properties and durability in marine environments. This article aims to provide a detailed overview of its chemical composition, mechanical properties, heat treatment status, dimensional range, impact testing, primary application scenarios.

Chemical Composition:
The chemical composition of LR DH69 steel plate is carefully balanced to ensure optimal properties. It typically comprises carbon (C), manganese (Mn), phosphorus (P), sulfur (S), silicon (Si), and other alloying elements such as nickel (Ni) and chromium (Cr). The precise composition varies depending on the specific requirements of the end-use application.

LR DH69 extra high Strength Chemical Composition
Grade	The Element Max (%)
Grade	C	Si	Mn	P	S	Al	N
LR DH69	0.20	0.55	1.70	0.030	0.030	0.015	0.020
	Nb	V	Ti	Cu	Cr	Ni	Mo
	0.02-0.05	0.03-0.10	0.02

Mechanical Properties:
LR DH69 steel plate exhibits exceptional mechanical properties, including high yield strength, tensile strength, and elongation. These properties allow the material to withstand the rigors of marine conditions, including wave impact, corrosion, and fatigue.

LR DH69 extra high strength property
Grade		Mechanical Property			Charpy V Impact Test
Grade	Thickness	Yield	Tensile	Elongation	Degree	Energy 1	Energy 2
LR DH69	mm	Min Mpa	Mpa	Min %	-20	J	J
	t≤50	690	770-940	16%		46	69
	50＜t≤70	690	770-940	16%		46	69
	70＜t≤100	690	770-940	16%		46	69
Note: Energy 1 is transverse impact test, Energy 2 is longitudinal

Heat Treatment Status:
The heat treatment status of LR DH69 steel plate is critical to ensuring its mechanical properties and weldability. It is typically supplied in a normalized or controlled rolling condition, which involves heating the steel to a high temperature and then cooling it slowly to eliminate internal stresses and improve its microstructure.

Dimensional Range:
LR DH69 steel plate is available in a wide range of dimensions to cater to different shipbuilding requirements. The thickness can vary from several millimeters to several centimeters, depending on the specific application. The width and length are also customized to meet the needs of the project.

Impact Testing:
Impact testing is a crucial aspect of LR DH69 steel plate, as it assesses the material's ability to resist brittle fracture under impact loads. This testing is typically conducted at specific temperatures to ensure the steel's ductility and toughness in extreme conditions.

Primary Application Scenarios:
LR DH69 steel plate finds its primary applications in shipbuilding and offshore structures. It is widely used in the construction of cargo ships, container ships, tankers, and cruise ships due to its superior strength, weldability, and corrosion resistance. It is also suitable for offshore platforms, pipelines, and other marine structures exposed to harsh environments.