Min Jia-Your Dependable Double Reduced Tinplate Manufacturer in China

Min Jia is your solid manufacturer of double reduced tinplate in China. We have been in supplying industry for about a decade. We are professional enough to manage such manufacturing double reduced tinplate on a large business.

Our company has well trained workers who are giving excellent work especially making high-quality double reduced tinplate. Min Jia double reduced tinplate is naturally thinner and more durable than that of the single reduced tinplate. Its steel is manufactured for the second time with lubricants.

The Min Jia double reduced tinplate is combined with greater strength and acceptable flexibility. You can save more in terms of economic savings when you prefer to use double reduced tinplate. We provide lists of its related products for your selections. Your desired type of double reduced tinplate is our priority.

As your responsible manufacturer, you can expect that in the short time possible we can immediately process your orders. We are manufacturing a lot of pieces of tin cans including double reduced tinplate in a day. That assures you that we can supply even a large quantity of your orders.

Look for accurate double reduced tinplate based on your required applications on Min Jia company. We have excellent packaging which is capable even for sea transportations. So you don’t have to worry about importing safely your double reduced tinplate wherever you are in the world.

Email or communicate with us for more information about double reduced tinplate!

Double Reduced Tinplate: The Ultimate FAQ Guide

If you have any question about double reduced tinplate, you will find the answer right here.

Because this guide covers everything you should know about double reduced tinplate.

Keep reading to learn more.

What is Double Reduce Tinplate (DR)?

Double reduced tinplate

Double reduced tinplate is a material that is first cold-rolled and annealed. It is then cold-reduced a second time before being annealed, either by batch or continuous annealing process, and then lubricated.

DR tinplate is usually thinner and stronger than the ordinal tinplate. The final thickness is an average of 0.14-0.24mm. The thickness can, however, go as low as 0.12mm, depending on your requirements.

What is Double Reduced Tinplate Raw Materials?

Raw materials for the production of Double reduced tinplate include;

Base Steel Sheet

The application of the tinplate determines the base steel to make the DR tinplate. The steel choice will determine the quality of the products.

There are three base sheets of steel to choose from; MC, MR, and L. The composition of the base steel includes: Carbon -0.05-0.12%, Manganese – 0.3-0.6%, and Sulphur 0.05% maximum.

They may contain other elements in small quantities.

Tin

Tin is used to layer the base steel and protect it from corrosion and other weather-related issues. The tin used should be at least 99% tin and less than 0.04% of other metals for DR tinplate.

The thickness of tin later on the Double Reduced tinplate is in the range of 0.10-0.15um.

Oil

The oil used on the DR tinplate is Dioctyl sebacate of 0.005gms/m2, palm oil, or any other food-grade oil. It is used to lubricate the tinplate

How is Double Reduced Tinplate Manufactured?

The Double reduced tinplate manufactured in the following steps:

Step 1: Pickling and Publication

This involves dipping the steel base in hot, dilute sulfuric acid to remove debris and prepare it for cold rolling.

Step 2: Cold Rolling

The material is passed and compressed between two rollers. Cold rolling occurs at room temperature. It produces material that is stronger but thinner with tighter tolerances than the hot rolled steel.

It also gives the material a better surface finish. The downside of it is that it increases internal stress that has to be removed through another process.

Step 4: Annealing

After cold rolling, steel is hardened. Annealing is the heat treatment given to the tinplate material to soften it for machinability.

Steel is held at high temperature over a furnace at an elevated temperature (soaking) and then cooling off.  Steel can be either batch annealed (BA) or continuously annealed (CA).

Step 5: Second Cold Rolling

The second cold rolling can be continuous or reversed back to the 1st cold rolling machine. The double rolling will reduce the thickness of the tinplate further. After this process, the edges of the material are trimmed in preparation for tinning.

Step 3: Washing and Drying

Jets of hot water or steam are used to remove oils and any debris from the material. It is then dried before the next stage.

Step 4: Lubricating

A layer of oil is applied to prepare the material for tin coating. Palm oil, Dioctyl sebacate of 0.005gms/m2, or any other food-based oil is used.

Step 5: Tin Coating

A thin layer of tin is applied through the electrolytic method. The material is passed through a tank of electrolyte tin salts. Here the tinplate may be equally coated or differentially coated.

Equally coating is applying an equal coat of tin layer on both sides of the material. Differentially coating applies one side with a thicker layer of tin or none on one side of the material.

Tin will give the tinplate a beautiful appearance. It also protects the material from rust and corrosion, making it suitable for packaging food and drinks.

What are Double Reduced Tinplate Uses?

DR tinplate products

The most common uses are in the food industry and beverage industry.  DRT is used to make tin cans for dry foods such as coffee and tea, candy and biscuit packages,

Double reduced tinplate does not allow air inside, and it’s easy to refill without spillages.

This makes it excellent for liquid packaging such as beer, fruit juices, or tomato purees, among others.

Because of its unbreakable and stable nature, it’s also used in the chemical industry to transport or store hazardous substances. It’s also ideal for making grease cans, chemical cans, etc.

Its ability to seal and reseal easily makes it an excellent packaging material in the pharmaceutical sector. It’s used for medicine packages and sterile cans.

DR tinplate is also used in the tobacco industry for cigarettes packages

The cosmetic industry likes it for its printability. Brands are easy to make creative and attractive prints. Because of this factor, DRT is used to make aerosol cans for air sprays, beauty oil packages, etc.

DR tinplate can be used to make lids and screw caps.

What are the Advantages of Double Reduced Tinplate for Food Packaging?

As you know, DR tinplate has a wide range of uses in the food and beverage industries.

The material is used to make tin food cans, beverage ends, tin cans for baking and soup can lids, etc.

Its popularity in the foodservice industry is due to the following reasons:

• Double reduced tinplate is made in a way that it can make products of various shapes and sizes for diversified consumer needs.
• It is non-toxic, making an excellent choice in making food and beverage packages.
• The material is environmentally friendly. Its production process contributes little pollution to the environment.
• DR tin plate has good performance on anti-rust and formability.
• The material can be recycled many times after being used in containers without losing its mechanical properties.
• Double reduced tinplate is of high quality and can be used to make attractive packages like gift boxes and accessories.
• The products made of DR tinplate are hygienic. This protects the consumer because the food and beverage packed have no potential for food poisoning.
• Logos, trademarks, and any design the client may need can be easily printed or embossed in DR tinplate products.
• It is economically friendly and durable.

What are the Mechanical Characteristics of Double Reduced Tinplate?

The main mechanical characteristics of double reduced tinplate are:

High rigidity: DR tinplate’s high rigidity ranges between 70-80 degrees as measured on the standard Rockwell 30T scale. It has a high breaking load of 60kgr/mm2.

Tensile strength and elongation: the tensile strength of double reduced tinplate is about one-sixth to one-eighth that of ordinary tinplate.

Its elongation is only 40%-50% that of ordinary tinplate.

Tensile stress-strain curve: double reduced tinplate has a lower yield strength and stiffness than ordinary tinplate.

Other properties include good corrosion resistance, easy weldability and formability, low aging, and excellent insulation.

What are the Available Dimensions of Double Reduced Tinplate?

Double reduced tinplate comes in sheets or coils with a thickness ranging from 0.14mm -0.29mm- in multiples of 0.005mm. They come with a width of 650mm to 1250mm. The ultimate width choice will depend on the desired characteristics for the final application.

How does Batch Annealing (BA) Compare with CA (Continuous Annealing) Double Reduced Tinplate?

Continuous annealing

The process of cold rolling for double reduced tinplate hardens the steel substrate. Annealing is done to soften it.

During annealing, the steel is held at a high temperature over a furnace, heated, and then cooled.

Continuous annealing involves uncoiling, joining strips, and passing them (together) through a furnace.

 Batch annealing

In BA, several coils are heated as a batch for three days. The output per hour could be around 1.4 tons.

Batch annealing is done in temperatures below 725 degrees C, while continuous annealing is done at about 800 degrees C but quickly.

CA has better mechanical properties and hardness than BA

Is Double Reduced Tinplate and Single Reduced Tinplate the Same?

No.

The production process is different for DR tinplate and SR tinplate. SR is cold-rolled, then annealed and temper rolled, and electrolytically tin coated.

After the first cold rolling and annealing, DR undergoes a second cold rolling, and then it’s lubricated. This strengthens the tinplate further with a thickness of 0.24mm-0.21mm.

DR is stronger and thinner with a hardness of 72+/-3 in the HR 30T scale, while SR has a 53+/-3 to 61+/-3 hardness.

What is Double Reduced Tinplate Thickness Range?

Double reduced tinplate is supplied as sheets or coils. They have a thickness range of 0.14mm to 0.21mm and a width of 650mm-1250mm.

The thickness of the tin coating is 0.56gsm to 16.8gsm.

The choice of tinplate thickness depends on the client’s specific requirements.

This is because different steel combinations will give different ranges of DR tinplate for various uses.

DR has a temper of 71 to 75 (DR7.5, DR8, DR8.5, and DR9) on Rockwell Hardness values 30T. Temper finish also determines the end-use of the tinplate.

What are the Available Surface Finish Options for Double Reduced Tinplate?

Double reduced tinplate comes in the following surface finish options:

What is Differentially Coated Double Reduced Tinplate?

Differentially coated double reduced tinplate is produced by double cold rolling and has a different coating on each surface.

The tin coating layer may also vary on both sides of the tinplate.

The inner face is coated depending on the contents to be packaged. The client determines the outer coat.

Customers need to give their coating requirements according to their aesthetic needs for external coating.

Differentially coated DR tinplate is used to make aerosol cans, food and beverage cans, water tanks, gift packages, paint containers, and chemical cans, among other applications.

How is Differentially Coated DR Tinplate marked?

Differentially coating specifications

Differentially coated tinplate is marked ONLY on one side surface to differentiate it from equally coated. The marking may be on the face with a heavy coat.

The marking shall appear: a) dull straight (continuous) parallel lines of 1mm wide spaced at an interval of 75mm on the face with a heavier coat. b) Dull straight parallel lines alternately interrupted on the face with a lighter coat.

Option (a) shall always be preferred if no option is communicated at the time of ordering.

Here is an example of how and where to show the markings on order:

D2.8/5.6- marking should be on the outer side of the coil or the 2.8 coated faces.

D5.6/2.8- marking shall be on the outer side of the coil or top marked on the 5.6 coated faces.

2.8/5.6D- marking shall appear at the inner side of the coil or the bottom of sheets, marking the 5.6 coated face.

5.6/2.8D- marking shall be on the inner side of the coil or at the bottom of sheets and marking the coated face of 2.8.

How is Double Reduced Tinplate Printed?

Printing on double reduced tinplate means transferring a photo or design onto the tinplate material.

The photolithographic process is used to print DR tinplate. Here, a printing plate where the artwork is to be printed is made.

The plate is then greased and the parts not to be printed sprinkled with water.

A rubber blanket is used as the material where design is shifted to.

The design is then transferred onto the surface.

A rubber blanket acting as the design carrier is placed between the metal sheet and the plate for printing.

A plate of the original logo, art, or text is reproduced in transparent form and copied to the plate (printing). Printing is done as dot images.

The value of color determines the dot proportions within a specific area to be printed.

Colors are separated into primary colors; yellow, blue, and magenta for full-color prints.

Several plates are made depending on the number of colors to be printed, and a separate black plate is made.

A small allowance is then left from the edge of the tinplate to the artwork.  This is meant to give room for the proper welding of the material during fabrication and processing.

When the printing is done, the tinplate is put in the drying room to dry in moderation; not too slow, not too fast as it is easy to cause scratches in the transmission process.

The ink is allowed to dry appropriately to achieve quality printing.

The drying room is usually dust-free, dry, and away from direct sun.

What are the Ink Requirements for Printing Double Reduced Tinplate?

Ink should be non-corrosive. The purpose of printing the tinplate is to avoid contamination when food substances contact the packaging can.

The ink should also be adhesive to prevent scraping off during bending or stretching of the tinplate.

A white layer of paint coat under the ink coating will improve its adherence.

Ink adhesion will also prevent scratches on the inside of the can.

An example of a light white paint that’s prone to fade and age is primer epoxy.

Hygiene and safety requirements demand that the paint should be non-toxic and tasteless.

This is to prevent contamination of packaged content, especially for food and drink packaging applications.

The ink is also required to be light and weather resistant.  Some canned food stays in storage for a long time, so the ink should not fade onto the food.

Besides the general offset printing ink, tinplate printing ink should be heat resistant. It should be able to adhere well to the ink film and hard enough to be affected by any impact.

Because it can be used in high heat applications, it should also resist light and heat during processing.

To further protect the consumer, the ink should not peel off or bleed at high temperatures, especially when packaged content is sterilized.

Water-resistance ink is left to dry after the application, suitable for the food and drink packages.

International standards require that ink should not have heavy metals.

This is to avoid metal poisoning on the packed food, especially chocolates, candies, biscuits, among others.

How does Printing vs. Lacquering compare for Double Reduced Tinplate?

Lacquering gives DR tinplate material various beautiful colors by covering it with anti-corrosion lacquer under vacuum.

The process helps to prevent material corrosion from water or air.

Printing uses mechanical means to transfer images from printing plates and other media onto the DR tinplate materials.

Thereby, it simply reproduces text or artwork onto the printing surface.

Lacquering causes the surface to become slightly porous, risking moisture content to get in and cause corrosion to the tinplate.

On the other hand, printing on the metal gives a much better result from an aesthetic perspective because it makes the image appear almost painted onto the product.

Also, printed tin can be buffed and polished to a high shine which isn’t possible with just a lacquer coat.

With printing on tinplated steel, there is no post-curing required and thus has a fast turnaround time.

Lacquer is more elegant to the look, but the printing ink in tinplate provides a better level of protection.

Consider this information while considering between printing and lacquering your tinplate.

There is the availability of a wide array of colors to choose from when printing DR tinplate.

This means you can achieve what you want for your brand in artwork and text of different colors.

How do you Test Double Reduced Tinplate?

Two main tests are used to verify the quality and performance of double reduced tinplate:

Proof of Hardness Test

The rigidity or hardness of DRT as measured on Rockwell 30T is in the range of 70-80 degrees.

It’s possible to take the measurement on Rockwell 15T and convert it to Rockwell 30T values.

The R15T has 60kgr/m2 as its breaking load.

Durometer is not suitable to measure the hardness of the DR tinplate because of the thin size of the tinplate.

European designation for DR tinplate is identified with the letters ‘DR’ followed by a three-digit figure in the code.

America codes it as ‘DR’ followed by a single digit.

Springback Temper Testing

Using a spring-back temper tester, it is possible to measure the permanent deformation of the metal. Subject it to bending stress through the temper tester.

A sample of fixed dimensions cut from the DR tinplate is bent using the temper instrument.

For fair results, the sample should be cut with a sharp blade to avoid a burr caused by the blunt blade.

Sample should be of size: length 152.4mm, width 23.8mm. Use the larger side of the sample parallel to the rolling steel direction.

Bend the specimen perpendicularly to the grain direction to get correct values.

The thickness of the sample should be confirmed with a micrometer.

How to measure:

• Fix the sample parallel to the forming arm and secure it
• Quickly tilt the forming arm to 180degrees and back to its position.
• The center of the sample will curve. Measure the residue angle of the bent sample.
• The thickness (measured by the micrometer) and the angle attained in this sample are used to determine the elastic limit of the DR tinplate. (Use the table (unique with measurements) supplied with the measuring equipment to determine the value).

What are the Environmental Considerations of Double Reduced Tinplate?

Double reduced tinplate is made of recyclable material. It can be recycled more than a dozen times without losing its mechanical properties.

The recyclability of DR tinplate protects both the environment and the health of the general population.

Other ways that are used to put the health of the consumer and the environment include;

Reduction of the Use of Chemicals, Acids, and Oils used during Production

With the recycling of raw material, there is an energy reduction of 60 percent and a significant reduction in air pollution.

Improved passivation process means cans are of higher quality in preserving and storing canned food and beverages.

Sustainability of Lacquers

New, improved methods of processing the tinplate achieve lighter and stronger containers and fewer raw materials.  Over the past three decades, a weight reduction of 46% has been achieved.

What are the Considerations for using Double Reduced Tinplate?

Things to keep in mind when using double reduced tinplate include;

• Rolling direction should be considered during the production of cans or containers.

They should be parallel to the base of the can. If that’s not achieved, the container/can develops cracks.

The cracks reduce the lifespan of the packaging materials made. It also may cause rusting of the cans if the metal is exposed.

• Blades should be sharp enough during cutting of the double reduced tinplate.

Blunt blades may cause the tinplate to develop cracks at the edges or along the cutting line.

Cracked edges will affect the quality of the end product.

• Fibers may also be broken with the use of a pair of rollers, also known as flexors. This will make the container achieve its intended purpose.
• The presence of fibers hardens the material, which requires to be reprocessed to reduce its thickness.

The end product will be cheap and of less quality than the single rolled tinplate.

Are there any Special Requirements for Packaging and Transporting Double Reduced Tinplate?

 Double reduced tinplate ready for transportation

Yes.

Double reduced tinplate is very easy to be oxidized.

It should be packed in a clean, dry atmosphere.  It should be wrapped in waterproof material and thermal insulation material.

The DR tinplate should be cushioned at the four corners for sheets and around the coil for DT tinplate coils. This helps to prevent scratches and deformation during transportation.

It should be packed in standard export seaworthy packing with three internal wooden-barred pallets or two internal wooden-barred pallets and a plasterboard-barred pallet.

The pallet is as protection to avoid direct contact with the ground.

The packaging should be firm and tight and should meet the requirements of environmental protection.

International standards and technical specifications should be adhered to when considering the outer packaging size.

The packaging should be well labeled, showing the type of tinplate, size, marking specifications, country of origin, and destination country.

For any question or inquiry about double reduced tinplate, feel free to contact us.