Stainless steel coils are a strong and durable material that can withstand high temperatures, pressure, and stress without deformation or failure. These coils are typically produced through a process called cold rolling, where stainless steel sheets are compressed between rollers to achieve the desired thickness and shape.
Stainless steel coils are available in a wide range of grades and finishes. The most common stainless steel grades used in coil production include 304, 316, 430, and 201, each with its unique properties and characteristics. In short, stainless steel coils are versatile and durable rolled sheets of stainless steel used across industries for their exceptional strength, corrosion resistance, and aesthetic appeal.
There are mainly two types of coils.
Aspect | HR Coil | CR Coil |
Production Process | Produced by hot rolling steel at high temperatures | Produced by cold rolling steel at room temperature |
Surface Finish | Typically has a scaled and rough surface | Has a smoother and more uniform surface |
Thickness Tolerance | Tends to have less precise thickness control | Offers better thickness control and uniformity |
Mechanical Properties | Generally has lower hardness and strength | Exhibits higher hardness and strength due to cold working |
Uses | Commonly used in structural applications and fabrication | Preferred for applications requiring precise dimensions |
Grades of Coils
Mentioned in excel sheet.
- Hot Rolled (HR) Coil Finishes:
- No.1 Finish: This is the most common and basic hot-rolled finish. It has a rough, scale-covered surface and is not suitable for applications requiring a smooth appearance.
- No.2D Finish: A dull finish with a slight cold-rolled appearance. It is smoother than the No.1 finish but still retains some surface imperfections.
- No.2B Finish: A smooth, moderately reflective finish with a bright appearance. It is achieved by cold rolling, annealing, and pickling after hot rolling.
- No.3 Finish: A semi-polished finish with a dull appearance. It is achieved by grinding the surface to remove defects.
- No.4 Finish: Also known as a satin or brushed finish, it has a smooth, uniform appearance with fine parallel lines. Achieved by polishing with abrasives.
- BA (Bright Annealed) Finish: A highly reflective, mirror-like finish suitable for decorative applications. Achieved by annealing in a controlled atmosphere to prevent oxidation.
- Cold Rolled (CR) Coil Finishes:
- 2B Finish: Similar to No.2B finish in HR coils, it has a smooth, bright appearance with good reflective properties.
- 2D Finish: A dull, matte finish achieved by cold rolling with annealing and descaling.
- 2BA Finish: A bright annealed finish similar to BA finish in HR coils, providing a mirror-like appearance.
- 2BB Finish: A bright, smooth finish with improved flatness and surface quality compared to standard 2B finish.
- 2R Finish: A reflective finish achieved by cold rolling with a bright annealing process.
2B Finish
A smooth and reflective finish that gives a mirror-like look to the surface. A 2B finish is achieved on a stainless steel sheet or other materials by the process of cold rolling. Heat treating and pickling are also done to achieve such a fabulous finish.
No.4 PVC
PVC or Polyvinyl Chloride finish is a metal finishing used on sheets made of Stainless steel, Inconel, Aluminium, Nickel, and more. It’s a cost-effective coating that helps in the bending of the sheet metal and protection of the structural components over time.
No.8/ Mirror Finish
The No.8 finish is another shiny or glossy surface finish applied on sheets, plates, and coils. It has almost mirror-like reflections that can be used for a wide variety of applications. It is done by buffing with abrasive compounds, followed by rouge-like compounds.
BA Finish
BA or Bright Annealed finish is a specific surface finish made for cold-rolled stainless steel. They are achieved on various materials but specifically made for stainless steel and SS 304 grade. The sheet, plate, and coils are annealed from an inert gas atmosphere after a cold rolling process.
Designer Finish
We also provide a designer finish that can ensure numerous designs for a better look and feel. Texture, fabrication drawings, and metal design is factored in with sheets, plates, and coils.
Hairline Finish
These materials have a fine hairline texture with the best finish and feel. A hairline grain is processed with metal bristle brushes on a continuous turning wheel to achieve a perfectly hairline-textured finish. It is applied to several materials like Stainless steel, Aluminium, Nickel, and others. The finish is featured in sheets, plates, and coils.
Honeycomb Finish
Have your sheets, plates, and coils in the fabulous honeycomb design It is famous for its hollow honeycomb-like hexagonal shape. It is commonly used in interiors/exteriors and in architectural structures.
Properties of Hot Rolled Coils-
Pickled:
Pickling is a process that removes any impurities, oxidation, rust, and scale from metal surfaces, making them corrosion-resistant. Before most cold rolling processes, that is previously hot rolled undergoes a pickling process to remove scales from the metal surface to make it easier to work with.
Annealed:
The annealing is a process in which the sheets, coils, or plates are heat treated to alter their mechanical or electrical properties. Annealing removes any defects, uniforms the chemical composition, and fine grains, and softens the metal for cold working. It gives the metal a mirror-like finish and improves its machinability, ductility, and toughness.
Dimensions for HR coil-
Sizes- | All sizes available |
Thickness | All sizes available |
Width | All sizes available |
Length | As per requirement |
Type of slitting- | Narrow width 2000 meter width 1250 to 2000 meter width |
Dimensions for CR coil-
Sizes- | All sizes available |
Thickness | All sizes available |
Width | All sizes available |
Length | As per requirement |
Type of slitting- | Narrow width 2000 meter width 1250 to 2000 meter width |
Slit coils-
A slitting coil is a process of cutting a wide coil of metal into narrower coils of specific widths. The process involves feeding the coil through a slitting machine, which has circular blades that are adjusted to the desired width. As the coil passes through the machine, the blades cut the coil into narrow strips, which are then rewound into smaller coils.
Slitting coils are a highly precise and efficient process, which allows for a high degree of accuracy and consistency in the width and thickness of the coils produced. The process can be customized to meet the specific requirements of different applications, including different widths, thicknesses, and types of metal.
Applications of Stainless-Steel Coils-
Automotive Industry:
Stainless steel coils are used in the production of automotive components, such as exhaust systems, catalytic converters, and fuel tanks, due to their high strength, corrosion resistance, and durability.
Construction Industry:
Stainless steel coils are widely used in the construction industry for structural applications, such as roofing, cladding, and reinforcement, due to their high strength, durability, and corrosion resistance.
Food Processing Industry:
Stainless steel coils are used in the food processing industry for the manufacture of equipment, such as conveyor belts, processing tanks, and food handling equipment, due to their hygienic properties, resistance to staining, and easy-to-clean surfaces.
Chemical Industry:
Stainless steel coils are used in the chemical industry for the manufacture of equipment, such as pressure vessels, storage tanks, and piping systems, due to their excellent resistance to corrosion and high temperatures.
Medical Industry:
Stainless steel coils are used in the medical industry for the manufacture of medical equipment, such as surgical instruments, dental instruments, and implants, due to their biocompatibility, easy-to-clean surfaces, and resistance to staining.
Manufacturing Industry:
Stainless steel coils are used in the manufacturing industry for the production of a wide range of products, such as appliances, furniture, and machinery, due to their strength, durability, and corrosion resistance.
Aerospace Industry:
Stainless steel coils are used in the aerospace industry for the manufacture of components, such as turbine blades, exhaust systems, and aircraft frames, due to their high strength, lightweight properties, and corrosion resistance.