Tinplate Steel Coils For Food Cans
Tinplate steel coils for food cans are a major raw material in the production of metal packaging. Its good preservation, light protection and sturdiness make it popular in the food industry.
It is made by the electrolytic tinplate process. This involves the coating of strip steel with tin using flow melting.
Corrosion Resistance
Tinplate steel is a metal product that combines the strength and formability of cold-rolled low carbon steel with the corrosion resistance, solderability and aesthetics of tin. It is a highly versatile material that can be used to make a wide variety of containers and products including food, beverages and general packaging. Its hygienic and non toxic barrier properties help to protect the contents of food cans from impurities, bacteria, moisture, light and odours.
The tin coating also provides a barrier against oxygen, which prevents the formation of rust on the metal surface. This is particularly important during the canmaking process because rust can cause tainting of the product inside.
The tin layer is typically applied to a low carbon steel base that has been tempered and annealed. Typical base steels include black plate, also known as tin free steel or TFS, electrolytic tinplate (ETP) and hot rolled galvanized steel, commonly referred tinplate steel coils for food cans to as HRG or CR sheet. All of these grades are capable of producing tinplate, but different processing options yield varying performance characteristics.
Durability
Tinplate steel is a highly durable material that has been used for decades in food cans. Its non-toxic barrier properties protect food from impurities, bacteria, moisture, light and odours. It also offers 100 % recyclability. It is also safe to use and easy to transport.
It can be made into a coil, which is then rolled into a can or other product. The material is annealed to soften it and remove internal stresses. This process can be done using continuous or batch annealing. Continuous annealing involves continuously passing the tinplate coil through heaters. Batch annealing involves stopping and baking each coil individually.
The steel substrate is electrolytically tin coated after cold reduction and annealing. The tin coating is deposited on the steel surface to form a thin, protective layer. The tin can be coated with a stone finish or bright tinplate. A stone finish is better for food containers and trays. It is resistant to scratching and has a high gloss.
The tinplate steel coils are treated with passivation code 300 (beverage) or passivation code 311 (food). They are also lubricated with Dioctyl Sebacate oil of 2.0 -6.0mg/m2. It is a low toxic and eco friendly product.
Environmentally Friendly
Although metal tinplate food cans are already the stars of the circular economy with their high recycling rate, our experts at thyssenkrupp Steel aim to make the material even more sustainable. They are doing so by reducing energy consumption, using less raw materials and developing new technologies.
Electrolytic tin plate, also known as tin-plated steel (SPTE) is cold rolled low carbon steel strip coated with commercial pure tin on both sides. Tin primarily acts to prevent corrosion and rust. It combines the strength and formability of steel with the corrosion resistance, solderability and aesthetic appearance of tin in one product. It is non-toxic, highly corrosion resistant and has excellent ductility.
A wide variety of foods are packed in tin cans for preservation and transportation. Some of these products are very acidic and can corrode the coatings of the metal containers. Other foods may contain high concentrations of nitrates, anthocyanins, sulphur dioxide or metallic sulfides which can react with the coatings to cause black staining. These issues can be resolved with the use of internal and external coatings such as zinc oxide based coatings.
Easy to Weld
Tinplate is a material composed of thin steel coated with tin. It is nontoxic and corrosion resistant, which makes it ideal for the production of food cans. It is also inexpensive and easy to process. In addition, it is durable and strong, and is easily welded.
The tin coating is applied by electrolytic deposition on the surface of steel strip. This replaces the old hot-dipping method. This is now almost entirely automated, allowing factories to produce millions of cans every day.
Once the cans have been formed, they are welded together at high speed. The lid is then screwed on, and the bottom is sealed by welding it to the top of the can. The cans are then washed and dried, and a special coating is sprayed on them to stop them rusting when they contain food.
The cans are then filled with the product to be sold. A bright light is shone into them to check that they don’t have any holes, and any that do are rejected. They are then labelled and packed for shipping to retailers.
Recyclable
Unlike other metal packaging, tinplate is 100 % recyclable. It is also very hygienic as it is non-toxic and has good barrier properties to protect foods from impurities, bacteria, moisture, light and odours. It also has the advantage of being easy to weld, which avoids safety concerns associated with soldering and reduces the amount of metal used in the process.
During the production of tinplate, the Annealed Steel Strip steel strip is exposed to heat treatment at temperatures up to 750 degC. This annealing process is crucial for maintaining the base material’s crystalline structure. A new project called FlexHeat2Anneal aims to provide sustainable solutions for this annealing process.
Electrolytic tinplate (ETP) is thin steel sheet or strip coated with commercial pure tin on both sides. It is characterized by its beautiful metallic luster. It has excellent properties in corrosion resistance, weldability, and paintability. It is suitable for all types of food cans, especially carbonated soft drinks, canned fruits and vegetables, canned meat, canned milk and other beverages. It is supplied in standard export packing or according to customers’ requirements.
