Highway parapet posts

Highway parapet posts

H Metal supplies highway guardrail posts made of HEA steel beams. After we cut the beams to the lengths required in the project, they are heat galvanized.

Steel beam posts for highway parapets are indispensable elements of modern road infrastructure. They represent an investment in the safety and well-being of citizens. They also demonstrate the authorities’ commitment to reducing road accidents and ensuring smooth and safe traffic on highways.

A highway guardrail is made of profiled or smooth strips that can withstand the impact of a car at different speeds. They are mounted on steel beam posts. The posts are mounted 1 to 4 metres apart.

HEA steel beams, used as posts for highway parapets, offer a number of significant advantages. These advantages are both structural and economic. This makes them a preferred option in many road infrastructure projects.

ADVANTAGES OF HIGHWAY GUARDRAIL POSTS MADE OF HEA STEEL BEAMS

ADVANTAGES OF HIGHWAY GUARDRAIL POSTS MADE OF HEA STEEL BEAMS

Their robust structure minimises the risk of significant deformation or collapse, even following collisions at high speeds.

Thanks to their standardised shape and relatively low weight (compared to other types of massive load-bearing structures), HEA beams can be easily transported and assembled. This reduces the time needed for the construction or renovation of highway parapets.

Steel is a fully recyclable material, which means that the use of HEA beams contributes to sustainable construction practices. It reduces the carbon footprint of infrastructure projects.

The steel beam support for the highway parapet is a crucial element in ensuring road safety. It contributes significantly to the prevention of serious accidents. These supports are designed to withstand high impact.

Manufactured from high quality steel, these beams undergo rigorous testing and certification processes. They meet national and international safety standards. They are heat-galvanised to provide optimum corrosion resistance, ensuring a long service life even in severe weather conditions.

HEA beams

The installation of the steel beam supports for highway parapets is carried out with precision to ensure correct alignment and stability of the structure. They are firmly anchored in the ground, capable of supporting the metal parapets, which act as protective barriers for vehicles.

In addition to their primary safety function, the steel beam supports also contribute to the aesthetics of the roads. They can be painted or treated to blend in with the surrounding landscape. They therefore play an important role not only in protecting the lives of drivers and passengers, but also in creating a visually pleasing environment for all road users.

Quotations for HEA steel beams are made on a spot basis according to size, quality and quantity. In this respect we kindly ask you to send us these details by email office@h-metal.ro.

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The main steel manufacturers

The World Steel Association has published the statistics for June 2013. World raw steel production was 131.7 million metric tons, an increase of 3.3% compared to June 2012, but with the same average of 4.39 million tons/day as in May 2013.

Chinese production increased by 4.4 million tons between June 2012 and June 2013, but the average/day in June 2013 compared to May 2013 was actually 0.3% lower. Other countries that showed increases of over 200,000 tons between June 2012 and 2013 include Taiwan and Ukraine, while South Korea and Italy had a decrease of over 250,000 tons at the same period.

The main steel manufacturing countries in 2012 were China, Japan, USA, India, Russia, South Korea, Germany, Turkey, Brazil, and Ukraine.

Top steel manufacturing companies – 2012

ArcelorMittal was setup in 2006 by the takeover of the Western European steel manufacturer by the Indian manufacturer Mittal Steel. It is the largest steel manufacturer, responsible for over 6% of the world steel production.  It has its registered office in Luxembourg and operations in over 60 countries on four continents, Europe, America, Asia and Africa. ArcelorMittal manufactures finished and semi-finished products, such as cold-drawn sheet and hot-rolled sheet, bars, structural shapes, wire, pipes and tubes for various applications. The company has iron ore mining activities in Algeria, Brazil, Bosnia, Canada, Kazakhstan, Liberia, Mexico, Ukraine and the United States, as well as coal mining activities in Kazakhstan, Russia and the United States.

On 1 October 2021, Nippon Steel merged officially with Sumitomo Metal Industries, becoming Nippon Steel & Sumitomo Metal Company. It is the leading steelmaker in Japan with over 50,000 employees.

The company makes a wide range of steel products used for industrial machines and equipment, exported worldwide. Nippon Steel is also developing new businesses, such as chemicals, ceramics, electronic equipment and information and communication systems.

Hebei Group was setup in June 2008 through the merger of three smaller companies in Hebei Province, China. It is a state-owned company and has three main product lines: fine plate materials, vanadium-titanium products and high quality construction materials.

Boasteel Group is a state-owned company based in Shanghai, China. The company makes carbon steels, stainless steels and special steels. These steel products not only meet domestic needs, but are also exported to more than forty countries. They have wide application in industries such as automobiles, household appliances, petrochemicals, energy, transportation, aeronautics, etc.

POSCO is a company setup in 1968, with the registered office in South Korea. Steel production includes hot-rolled steel, sheet, wire, cold-drawn steel and stainless steel products. POSCO currently manages two integrated steel plants in South Korea, in Pohang and Gwangyang. In addition, POSCO manages a joint venture with US Steel, USS-POSCO, in Pittsburg, California.

Founded in 1958, Wuhan Group is the first Chinese giant in steel industry. Over the years, the company has developed a complete set of advanced processes for the manufacturing of iron, steel and mining equipment, coking and additional facilities. This makes it an important, high-quality manufacturing base for hot-rolled and cold-drawn sheet in China and contributes greatly to China’s economy and modernization. Currently, Wuhan Group is involved in three industries: the iron and steel industry, hi-tech and international trade.

Shagang Group is the largest private company in China. Annually, it manufactures about 29 million tons of iron, 35 million tons of steel and 33 million tons of laminated products, being one of the top five steel manufacturers in China. Since 2006, the company has purchased four smaller rival companies, and now it is China’s largest private steel manufacturer.

Shougang was established in 1919, having an accelerated growth since the establishment of the People’s Republic of China. Along with the reform of China and its opening to the outside world, Shougang has developed as one of China’s core corporations. The main activity of Shougang Group is the steel industry, the company having business in mining, electronics, building and real estate.

JFE is a corporation with the registered office in Tokyo, Japan. It was established in 2002, through the merger of NKK and Kawasaki Steel Corporation. At that time, NKK was the second largest steel manufacturer in Japan and Kawasaki Steel the third. The main field of activity is steel production, but it is also engaged in engineering, ship building and real estate rearrangement. The company has subsidiaries abroad including California Steel in the United States, Fujian Sino-Japan Metal in China and Minas da Serra Geral in Brazil.

Anshan Iron and Steel Group Corporation (Ansteel) is established in Anshan, Liaoning Province, China.

Anshan area is rich in iron ore, its reserves representing a quarter of the country’s total reserves. The company was setup in 1948 and had a great contribution to the national economic construction. After 60 years of construction and development, Anshan Group created a development model for three large manufacturing bases located in Anshan, Bayuquan and Chaoyang. These have an annual capacity of 25 million tons of cast iron, raw steel and laminated steel. The company can manufacture 600 classes of steel that are widely used in various fields of the national economy.

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Modern processes in the manufacturing of steel

The methods of steel manufacturing evolved significantly with the beginning of industrial production at the end of the 19th century. However, modern methods are based on Bessemer process. According to the World Steel Association, in 2011, raw steel production reached a new record of 1.527 billion metric tons. Of these, about two-thirds were made using BOS (basic oxygen steelmaking) process and one-third was made using EAF (electric arc furnace).

EAF – Unlike other processes, the one that uses the electric arc furnace generates high temperatures by means of electricity. The first such oven was designed by Paul Heroult. This is a technology that uses 100% scrap steel.

The furnace is divided into three sections: case, fireplace and roof. The process begins by lifting the roof and electrodes, loading the scrap steel, reducing agents and alloying elements; then, the electrodes are inserted and the roof is placed back. By means of these three graphite electrodes, a temperature of approximately 3500 degrees Celsius is created and the melting process takes place. Once the entire charge is melted, a sample is taken which shall be analyzed to determine the oxygen quantity to be blown for refining. For refining, the chemical composition is adjusted to meet the requirements of the product. The electric arc furnace has a 300-ton capacity, and the manufacturing process takes about 40-60 minutes.

The advantage of this process is that it may be stopped and started without associated high costs.

Another advantage is that it may only use recycled materials. For these reasons, the EAF process has grown steadily over the past 50 years, now being used in 33% of the world’s steel production.

BOF – In 1960, the development of a method for the separation oxygen from nitrogen on industrial scale allowed major progress in the development of the basic oxygen steelmaking furnace. Most large-scale production is achieved through the melting process by means of basic oxygen.

Molten iron with recycled scrap is poured into a large converter, coated with heat-resistant bricks.

Then, a water-cooled tube is inserted till its tip reaches above the melted metal. Pure oxygen is blown through this tube, which reacts with the carbon in iron, making sufficient heat to keep the charge melted. To maintain a temperature of 1600 degrees Celsius, quick lime and other melting materials are gradually added, as needed. When the oxygen is blown, carbon monoxide and other gases are released, forming sinter. It is required to blow 20-30 minutes for a 400-ton converter. The released gases are vacuumed by some fans, and at the end of the process the sinter is removed. The resulting steel is either cast in molds for the manufacturing of molded pieces, or is cast in ingots to be rolled down. This seems to be the most convenient process; besides the fact that it is quick, the fuel consumption is very low.

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History of steel

Steel is an alloy of iron and other elements: carbon, manganese, phosphorus, sulfur, silicon, traces of oxygen, nitrogen and aluminum. Carbon and the other alloy elements act as a hardening agent.

Steel has carbon content below 2.11%; iron-carbon alloys containing carbon over 2.11%  are called cast iron.

The history of steel begins in ancient times. The oldest steel object is a piece of hardware, excavated in an archaeological site in Anatolia (Kaman-Kalehoyuk) dating back approximately 4000 years.

When the carbon content is over 0.3%, the material becomes hard and brittle if it is sunk in water at a temperature of 850-900 degrees Celsius. Its fragility may be reduced by reheating at 350-500 degrees Celsius, a process called hardening. Judging by the micro-structure of the remaining artifacts, the Egyptians knew about this type of heat treatment around 900 BC. Thus, they made an ideal material for the manufacture of swords and knives. There is also evidence of heat-treated steel during the Han dynasty (206 BC – 25 AD). However, ancient civilizations did not fully master the methods of steel manufacturing, its uses were limited and subject to very long making processes.

The era of the legendary Damascus steel is between 300 BC – 1700 AD. The secrets of making this steel were lost in time, but the artifacts remained. The history of this steel has its beginnings in India, around 300 BC, but it gained recognition during the Crusades of the Middle Ages. Damascus steel could be bent under pressure without breaking. Recent studies suggest that carbon nanotubes were included in its structure, which would explain some of its legendary qualities.

A major breakthrough occurred in 1751, when Benjamin Huntsman established a steel mill in Sheffield, England. Here, the steel was obtained by melting iron ore and cast iron in clay melting pots at a temperature of 1500-1600 degrees Celsius, using charred coal as fuel. Sheffield became the center of melting pot steel production. In 1873, the peak year, production was about 110,000 tons, about half of the world production. The process spread to Sweden and France and then to Germany, where it is associated with Alfred Krupp’s works, in Essen. This process allowed the production of alloy steels for the first time, as the alloying elements could be added to the melted metal in the melting pot.

The process has been in decline since the early 20th century. It is believed that the last melting furnace was operational in Sheffield until 1968.

Before 1860, steel was an expensive product, manufactured in small quantities. The metal structures were made of wrought iron or cast iron.

The modern era of steel manufacturing is linked to the name of the British metallurgist Henry Bessemer. In the Bessemer process, raw cast iron is transformed into steel by blowing air through it, after its removal from the furnace. The process demonstrated by Bessemer in 1856 became successfully operational in 1864. This process is one of the most important production developments of the modern era. A similar process was used in the United States by William Kelly in 1851, patented in 1857.

A difficulty in the Bessemer process was that only low-phosphorus and sulfur-containing cast iron could be transformed.

An alternative process of steel manufacturing was developed in 1860 by William and Friedrich Siemens, in Great Britain, and Pierre and Emile Martin, in France. The open furnace was powered by air and combustible gas, which were preheated by burnt gases to 800 degrees Celsius. A flame temperature of 2000 degrees Celsius was attained, which was enough to melt the charge. Melted cast iron, cold scrap or a combination of the two could be used. By 1950, 90% of steel manufactured in the United Kingdom and the United States was made using an open furnace. But this process was time consuming.

Towards the end of the 19th century, with the development of electricity, it became possible to use electricity as source of energy in steel manufacturing. This is how the electric arc furnace was made.

It is a technology that uses 100% steel scrap, ideal for the manufacturing of low-alloy steel. In 1948, another process was developed by Robert Durrer, known as oxygen-based convector or LD convector (named after the Austrian cities of Linz and Donawitz). It is a refined version of the Bessemer process, the air blowing is replaced by oxygen blowing. Thus, capital costs, melting time and increased productivity decreased. Since 1960, the oxygen-based process has replaced open furnace and Bessemer process on both sides of the Atlantic.

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Customized products

H Metal delivers customized metallurgical products to be delivered ready for assembly on site. These products bring economic and time benefits to our customers. black sheet, ribbed sheet, square and rectangular pipe, profiles and europrofiles.


Cold forming is the operation of plastic deformation through which a flat semi-finished product is transformed into a hollow part or the processing of a hollow part is continued in order to increase its depth.
Cold forming is performed in molds, the action being single or double, reverse or direct. Depending on the dimensions of the stamping parts, the shape of the parts, but also the nature of the material of which these parts are made, cold forming can be done in a single operation or in several operations.

In the cold forming process, the deformation is done without preheating the body and is used for relatively small bodies.

By drawing, well-known profiles can be made, such as: corners with equal or unequal sides, U profiles, C profiles, Z profiles, having various dimensions of the base and wings. Also, by stamping, different types of atypical profiles can be made, apart from the standards in terms of shape and dimensions, as well as various parts / semi-finished products.

Punching holes The sheet metal sheets are stamped according to the model – ordered mold, with round, square, rhombus, Maltese cross holes, oval, triangle, arranged in line or interspersed, with a single shape or different mixed shapes. Punching has the advantage that it does not heat the material so for the galvanized sheet it is a plus, the zinc layer is not damaged.

Mechanical cuts to the guillotine.

By means of the mechanical cutting operation, different materials are cut into pieces, depending on the shapes and dimensions established for the purpose of their use and further processing. In this way, different atypical dimensions can be made outside the standards of flat / wide steel, sheet metal, etc.

Plasma / oxygen gaskets

Through this process, metallurgical products with large thicknesses can be cut in general, especially thick sheet, thick pipes, profiles, etc. After cutting with plasma or oxygen on the resulting edge after cutting, there are traces of burrs – smaller in plasma and larger in oxygen. With plasma or oxygen gas the products can be cut / holes both with straight shapes (lines) but also irregular shapes according to the drawings.

Galvanized

Hot dip galvanizing is the most effective method of protecting steel against corrosion for very long periods of time. the zinc layer applied by thermal galvanizing is several times thicker than that applied by electro-galvanizing, thus being even more resistant to corrosion.

Electrostatic painting

It is a superior technology for applying a paint, in the form of powder, on metal surfaces that are subsequently heat treated, thus ensuring a long resistance to wear and abrasion.

The main advantage of electrostatic painting is the high quality coverage compared to conventional painting methods.

Our company focuses on delivering quality products and offering services that meet the most demanding customers.

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What is calm steel?

Steel made in furnaces or converters is poured into steel molds (special molds made of cast iron), where it cools and solidifies. When it is poured into steel molds and the iron oxide content is too high, the steel shows the “boiling” phenomenon, which leads to the production of gas inclusions as structural defects. The amount of oxygen must be reduced to the limits accepted by the solidification process, this being done by deoxidizing the steel (also known as calm steel). To obtain steels with higher strength and toughness, deoxidizing elements are added, among which manganese, silicon and aluminum. Calming increases the price by 10-15%.

Depending on the degree of deoxidation, steels can be divided into three categories, symbolized by letters:

n – rimmed steel

s – semi-calm steel

k – calm steel

A rimmed steel is one in which the oxygen content is reduced to allow the carbon oxidation reaction to take place to a certain extent, after being poured into the steel mold. Deoxidation with manganese, silicon, aluminum, etc. is not enough in the case of rimmed steel (n). The chemical composition of these steels contains carbon between 0.04 – 0.09%, silicon between 0.005 – 0.002% and manganese between 0.25 – 0.04%. Due to the low consumption of deoxidizers, these steels are cheaper than calm ones and have a high plasticity.

Semi-calm steel (s) is an intermediate variant between non-calm and calm steel. The presence of carbon varies between 0.15 – 0.25%, silicon between 0.01 – 0.1% and manganese between 0.85 – 1.2%. The strength properties have values between those of the calm steel and the non-calm steel.

Calm steel (k) is the steel completely deoxidized. After it is poured in steel molds, the boiling of the steel stops because the amount of oxygen is too low. Deoxidation is performed with manganese, silicon, aluminum and other deoxidizers. Calm steel, the most commonly used, has a carbon content between 0.04 – 0.6%, silicon between 0.15 – 0.50% and manganese between 0.6 – 1.6%. This type of steel has good quality, a homogeneous structure and good strength characteristics, but it has low plasticity.

Calming or deoxidizing of steel is usually achieved by two methods:

1. Deoxidation by precipitation

2. Deoxidation by diffusion

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How much silicon should steel have for galvanization?

To obtain a uniform galvanized layer in terms of thickness and quality, the following values should not be exceeded in the steel composition: silicon (0.12% -0.25%), phosphorus (max. 0.25%), carbon (max. 0.2%), and manganese (max. 1.5%).

In metallurgy, it is known that silicon (Si) and phosphorus (P) are elements normally added to steel to improve its mechanical properties. At the same time, these elements influence the reactivity of the galvanizing process: too high concentrations determine layers thicker than normal, of high fragility.

Silicon is frequently added as reducing agent for steel manufacturing. During the galvanization process, silicon changes the composition of zinc-iron alloy layers, so that these continue to increase over time, and the reaction rate does not decrease as the thickness of the layer increases. Phosphorus has a similar influence on the formation of the coating, but to a lesser extent.

Steel with a silicon content of over 0.04%Si leads to a pronounced increase in the thickness of the deposited layer, the maximum value being around 0.08%Si. Between 0.08% Si and 0.17 Si, the Zn layer begins to decrease. It increases again for values ​​above 0.22%Si.

To enjoy the benefits of galvanized products, H Metal offers galvanized pipe, galvanized sheet and galvanized profiles.

The requirements of SR EN ISO 1461 include the cleaning and preparation of steel products, and hot dip galvanization. The information on the application and performance of hot dip galvanization is included in EN ISO 14713.

In terms of the reactivity of the galvanization process in relation to the steels that require quality coatings with zinc, there are four categories (quality classes according to the aspect of the surface), characterized by the percentage of silicon and phosphorus.

Category A – Si≤0.04%; P <0.02%

Steels in this category tend to have ordinary coatings with shiny surfaces. The coating structure includes the outer zinc layer.

Category B – 0.14 <Si≤0.25%; P <0.035%

Steels that are part of this class cause normal coatings but with major thickness. The aspect is still bright.

Category C – 0.04 <Si≤0.14%

Steels in this category may form excessively thick coatings (reduced impact resistance due to poor adhesion to the substrate). The coating has an obscure aspect and a coarse texture.

Category D – Si> 0.25%

Steels in this class cause excessively thick coatings (very low impact resistance), with poor adherence to the substrate. The aspect is from light gray to dark gray, with texture without the occurrence of stars.

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