Hot rolled coils are steel plates produced by rolling heated steel slabs through roughing

Hot rolled coils, also known as hot-rolled steel coils, are steel plates produced by rolling heated steel slabs through roughing and finishing mill stands. They are widely used in various industries due to their favorable mechanical and processing properties.

 

INTRODUCTION

 

Hot rolled coils, also known as hot-rolled steel coils, are steel plates produced by rolling heated steel slabs through roughing and finishing mill stands. They are widely used in various industries due to their favorable mechanical and processing properties.

 

 

APPLICATION AND SPECIFICATION

 

Hot rolled coils are utilized in a diverse range of applications, including: 

Structural Construction: Used in manufacturing various structural components such as beams, columns, and floor plates in buildings and bridges, thanks to their high strength and stability. 

 

Automobile Manufacturing: Extensively used in producing auto parts like body panels, doors, and floorboards, where high strength and corrosion resistance are crucial for safety and durability. 

 

Household Appliance Manufacturing: Applied in making the outer shells and internal components of appliances such as refrigerators, washing machines, and air conditioners, benefiting from their smooth surface finish and corrosion resistance. 

 

Steel Structure Manufacturing: Essential for fabricating various engineering machinery, equipment, and vehicles, ensuring stability and durability.

 

Container Manufacturing: Suitable for making containers like oil tanks, water tanks, and gas cylinders, meeting the safety and quality requirements of different applications.

 

Hot rolled coils come in various specifications: 

Thickness: Typically ranges from 1.2mm to 25.4mm.

Thicknesses below 1.2mm are considered thin plates, while those above 25.4mm are thick plates.

Common thicknesses include 1.5mm, 2.0mm, 2.5mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm, 8.0mm, 10mm, and 12mm. 

 

Width: Generally varies between 1000mm and 2500mm.

Widths below 1000mm are narrow plates, and those above 2500mm are wide plates.

Common widths include 1000mm, 1219mm, 1250mm, 1500mm, 1800mm, 2000mm, 2200mm, and 2500mm. 

 

Length: Typically ranges from 2000mm to 12000mm.

Lengths below 2000mm are short plates, and those above 12000mm are long plates.

Common lengths include 2000mm, 2438mm, 3000mm, 6000mm, 8000mm, and 12000mm.

 

ADVANTAGES

 

High Strength: Hot rolled coils exhibit strong cold deformation ability, providing high strength and excellent impact toughness, suitable for applications requiring heavy loads and pressure. 

 

Good Plasticity: They can be easily bent, stretched, and stamped into various complex shapes. 

 

Excellent Surface Quality: The surface of hot rolled coils is smooth and flat, with no obvious defects such as oxide scales or uneven dimensions, making them aesthetically pleasing and easy for subsequent processing and surface treatment. 

 

Easy Welding: They have good welding properties, allowing for secure connections with other materials or components through welding processes.

 

 

TREND AND PROSPECT

 

Environmental Compliance: With stricter environmental policies, the hot rolled coil industry is actively promoting green and low-carbon development through advanced production techniques and equipment to improve energy efficiency and reduce emissions. 

 

International Market Expansion: Thanks to global trade development and initiatives like the Belt and Road, the hot rolled coil industry is expanding into international markets, enhancing export scale and international competitiveness. 

 

Industry Consolidation: As competition intensifies, the industry is undergoing structural adjustment and optimization, with backward capacity being phased out and enterprises focusing on technological innovation and product upgrading to improve competitiveness and profitability.

 

INSPECTION STANDARD

 

Hot rolled coils are tested according to various standards to ensure quality and compliance: 

 

GB/T 713.2-2023: Pressure Equipment - Steel Plates and Strips - Part 2: Non-alloy Steel and Alloy Steel with Specified Temperature Properties. 

GB/T 3274-2017: Hot-rolled Carbon Structural Steels and Low-alloy Structural Steels - Steel Plates and Strips. 

GB/T 228.1-2021: Metallic Materials - Tensile Testing - Part 1: Method of Test at Room Temperature. 

GB/T 232-2010: Metallic Materials - Bend Test Methods.

GB/T 229-2020: Metallic Materials - Charpy Pendulum Impact Test Method. 

 

These standards cover chemical composition analysis, mechanical performance testing, surface quality inspection, dimensional accuracy testing, and non-destructive testing to ensure that hot rolled coils meet the specified requirements for corrosion resistance, thermal expansivity, mechanical properties, and other critical characteristics.