The production of metal pipes has been known since ancient times, when metal pipelines were used to transport water. But significant development of technology began in the 19th century.
Cold rolled steel pipe is a structure made by cold rolling. This is a metal processing process without heating to high temperatures, in which the material is subjected to deformation under pressure. The technology allows for high dimensional accuracy and improved mechanical properties. Cold-rolled pipes have a smooth surface and increased strength, which makes them in demand in various industries.
Scope of application of cold rolled steel pipe
Due to their high performance characteristics, round cold rolled steel tubes, which can be found at https://ukrstarline.ua/ru/chernyj-metalloprokat/stalnaya-truba/stalnaya-truba-holodnokatanaya-kruglaya, are used in:
- Industry. In mechanical engineering, they are used for the manufacture of engine elements, hydraulic systems, shafts and axles, where high precision and strength are required. In shipbuilding, they are used to create hydraulics and fuel supply systems.
- Construction. In this industry, cold-rolled pipes are used to create durable frames and load-bearing structures. Due to their durability and resistance to loads, they are often used in the construction of bridges, overpasses and other infrastructure facilities.
- Engineering networks. In the oil and gas industry they are used for transporting oil and gas, as well as for creating high-pressure pipelines. They are used in water supply, sewerage and drainage systems where corrosion resistance and tightness are important.
Also, round cold-rolled pipes are used in such areas as energy, medicine, automotive industry, furniture industry and in the production of household appliances.
Chemical composition and materials
The composition of steel used for the production of round cold-rolled pipes is regulated by GOSTs 8731-75 and 10701-82.
The main elements included in the composition are:
- Iron is the basis of the alloy and provides strength and magnetism.
- Carbon determines hardness and strength.
- Manganese - increases strength characteristics and abrasion resistance, improves weldability.
- Silicon - increases electrical resistance and machinability.
- Copper is responsible for corrosion resistance and ductility.
- Chrome - improves wear resistance and corrosion resistance.
- Nickel is responsible for toughness and rust resistance.
- Molybdenum - increases heat resistance.
Sulfur and phosphorus are undesirable impurities because they reduce ductility and weldability. The content of the above elements is strictly controlled, which ensures the necessary properties of the finished pipes.
Steel grades and their features
There are many grades of steel used to produce round cold rolled pipes. The most common ones include:
- Steel 10 is low-carbon, has good ductility and weldability, but relatively low strength.
- Steel 20 is characterized by good weldability and is used for the manufacture of pipes subject to light mechanical loads.
- Steel 35 is medium carbon, valued for its balance between strength and ductility, and good weldability.
- Steel 45 - has high strength and hardness, but has limited weldability.
Types and characteristics
Round cold-rolled pipes are classified according to various parameters: material, diameter, wall thickness and surface type. The latter can be glossy or matte. The material also comes in non-galvanized, galvanized and polymer-coated versions. The production method also differs:
Seamless is made from a solid steel billet by rolling with a gradual decrease in wall thickness and an increase in diameter. It is characterized by high strength, tightness, and can withstand high pressures.
Electric welding is made from steel strip by welding the edges followed by rolling. More affordable than seamless, but less durable and airtight.
Benefits of use
The products can withstand heavy loads and are therefore suitable for use in difficult conditions. Precise geometric dimensions ensure ease of installation and pairing of elements. The smooth surface makes the product aesthetically pleasing and simplifies the process of applying protective coatings; cleaning is as simple as possible.
Light weight reduces the load on structures, simplifies transportation and installation. Corrosion resistance allows the use of such rolled metal in aggressive environments. Good weldability makes it possible to resort to different welding methods. And most importantly, a round cold-rolled steel pipe is more affordable when compared with products made from copper or stainless steel.