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Hot rolled and cold rolled steel are both important raw materials in the production of many types of finished steel products. So what are hot rolled vs cold rolled steel? What is the difference between these two types of rolled steel and what are the applications of these two types of rolled steel?Let's explore more deeply with MRS Steel about the basic knowledge of hot rolled & cold rolled steel as well as the benefits it brings to businesses in many different fields through the article content below.Let's learn more about hot rolled steel and cold rolled steelLearn about hot rolled and cold rolled steelHot rolled and cold rolled steel are important raw materials in the steel production process. Both types of steel are metals whose production requires high technical skills and solid expertise. Next, let's learn about hot rolled steel vs cold rolled steel.What is hot rolled steel?Hot rolled steel is a type of steel produced through a hot rolling process at high temperatures, often exceeding 1000°C. This process can change the material and shape of the metal. Hot rolled steel products are often dark green, less shiny and lack aesthetics.Hot rolled steel are usually produced at high temperaturesWhat is cold rolled steel?Cold rolled steel is essentially a hot rolled steel that has been cooled and re-rolled at room temperature. After going through the process of gradually reducing the length of the cold rolled steel, it has appropriate dimensions and smooth surface quality. Because it goes through many processing processes, cold rolled steel often has a higher price than hot rolled steel, so product quality as well as aesthetics are also highly appreciated compared to hot rolled steel.Cold rolled steel has a smoother surface than hot rolled steelDifference between Hot-rolled and Cold-rolled steelTo distinguish between hot rolled and cold rolled steel, in addition to learning about the nature through the definition of each type of steel coil mentioned above, we need to differentiate through factors such as the normal thickness, price of each type, surface, and edge of the steel coil. In addition, we can consider additional factors such as tolerance, accuracy, and storage method of each type of steel coil. Let's see the differences between these two types of rolled steel through the table below.Table comparing the differences between hot rolled steel and cold rolled steelComparison criteriaHot-rolled steelCold-rolled steel Thickness>0,9 mm0,15mm - 2,0mmSurface, colorThe surface is rough, the blue-gray color turns rusty red after a long timeSmooth surface, light gray colorEdgeThe two edges of the roll are often rounded, rough, and turn rusty when left for a long timeUsually neatly trimmedTolerance The tolerance is larger due to the production process; the hot temperature cools down, so the steel deforms itself and cannot be controlledTolerances are tighter due to reduced temperatures throughout the process and strict control of the coolant actionPrice Cheaper than cold rolled steelHigher than hot rolled steelPreservationHot-rolled steel coils can be left outdoors for long periods of time without using coveringsShould be stored indoors and should be covered with a cover to prevent scratches on the steel surface.Advantages and disadvantages of hot rolled and cold rolled steelEach type of steel will have its own advantages and disadvantages. Let's learn about the advantages and disadvantages of hot rolled and cold rolled steel through the table below.Advantages and disadvantages of hot rolled steel and cold rolled steelCriteriaHot-rolled steelCold-rolled steel AdvantagesEasy to bend, easy to shapeSo Easy To PreserveGood bearing capacityLower price than cold rolled steelThe quality of the finished product is consistentThe surface is highly aestheticHigh durability and hardnessHigh accuracyDisadvantagesLow aestheticsDifficult to control size and shapeEasy to rustThe price is higher than hot rolled steelApplications of hot rolled and cold rolled steelHot-rolled and cold-rolled steel are two dominant types of steel on the market today. In addition to being commonly used in steel production, hot rolled vs. cold rolled steel are also indispensable materials for the production of many popular civil products today.Hot rolled steel is an indispensable raw material source in the steel production process. In addition to being a source of raw materials for the production of cold rolled steel, hot rolled steel is also used to serve the construction, mechanical, transportation, household appliances, and other industries that use billets, beams, and H-shaped steel.Cold rolled steel is mainly used to produce products such as steel sheets and galvanized steel coils with square and round details and smooth surfaces. Cold rolled steel has high aesthetics and precision, so they are often used in technical and aesthetic projects such as manufacturing cars, air conditioners, refrigerators, food containers, televisions,...Galvanized steel pipe is one of the applications of hot rolled steel 

The cold-rolled coil product is appreciated for its diverse applications and outstanding advantages. So how is cold rolled steel manufactured and what are its current popular applications, all questions will be answered in the article below!What is the cold rolled coil?Cold-rolled steel (trademarked CRC) is generated at the final stage of making steel from billet. Cold rolled coils are produced based on steel billets at low temperatures, more specifically, CRC has origin from hot rolled steel, then it will be processed through a cool process to make the surface become smooth and improve eye-catching brightness.Features of cold rolled coils Cold rolled coil often possesses a glossy surface by an oil layer treated in the rolling process. Besides the smooth surface, the product also offers outstanding durability advantages 20% higher than hot rolled coil. Along with that, cold rolled coil also has good impact resistance and ductile properties, so it is easy to bend and cut on requests.However, because it is still a metal, the cold rolled coil is easy to oxidize if it is not well preserved. Specifically, when the product exists in highly acidic or alkaline environments as well as it has to suffer from harsh weather environments, it will easily cause the steel surface to rust. To overcome this situation, the manufacturer usually has to periodically maintain it by applying a layer of oil to create a protective film for the steel core.Process production of cold rolled coilsThe steel production process will have to go through many separate stages that require strict control to ensure the hardness of the steel and avoid the case that the compositional elements are changed during the period of production.Stage 1 - Preparation of input materials and removing rust surface: the main input material of cold rolled coil is hot rolled coil. Hot rolled coil often brings low aesthetics through the rough appearance, so the manufacturer will proceed to spray a specialized acid directly on the surface to clean it.Stage 2 - Cold rolling stage: the manufacturer will use mechanical force with oil to roll the steel at a low temperature which is equal to room temperature at that time. This cold rolling process has the effect of making the steel structure stronger as well as changing the surface of the steel. However, in principle, the cold rolling process only changes the steel structure and it will keep the original steel's compositions. Because of those technical standards, cold rolling stages will require strict control in order to avoid surface cracking due to excessive force.Stage 3 - Soft annealing: steels that have undergone the cold rolling process will often be in hard condition, so they will be treated with a next step, which is soft annealing. The steel will now be annealed in an electric furnace containing 100% hydrogen gas to help remove the hardness after rolling, enhancing the ductility of the steel to make use of construction applications.Application in specific fieldsDepending on outstanding advantages such as shiny appearance, good loading resistance, cold rolled coil is widely used in the construction, manufacturing and mechanical industries. It also shows some benefits to human daily life. Specifically, some popular areas include:Construction works: taking advantage of the sturdy structure thanks to the low carbon content, people often use CRC for many construction purposes. Some practical applications in popular construction include making structural frames, purlins, ...Machine parts, spare parts for automobile and aircraft equipmentHousehold and consumer appliances: refrigerators, air conditioners, stoves,... Looking for cold rolled coil suppliers directly from Vietnamese factoriesSince the company was established and entered the market until now, MRS Steel has always maintained our mission of being a pioneer in the field of providing comprehensive steel solutions for international importers. Recognizing the important role of cold rolled steel, MRS Steel has been present and accompanies you in finding reputable sources.Based on many years of experience in the steel industry, we are confident in accompanying you in the steel import strategy. Vietnam steel market is considered a potential market with the participation of countless large and small manufacturers, acquiring a consultant  in steel will help you significantly optimize time and cost in the future. By finding out the source of goods as well as knowing the detailed price list, you can promptly adjust and orient your trading planning based on useful data.