Firstly, aluminized steel round pipes use to transport various liquids, gaseous media, and to create structural components. These are hollow products with a circular cross section, which is much less than the total length of the structure. Further, to select models, it is necessary to study the characteristics, operational features, current GOSTs.
Overview of manufacturing methods
Secondly, the general principle of production bases on the deformation of a steel billet. Depending on the acceptable technology, a welded joint forms, or seamless structures are made. This affects the technical parameters of products, future performance properties.
Manufacturing Methods:
- Seamless hot-worked. Firstly, the cylindrical work piece heats, and then a sleeve form using presses or machines with shafts. The final step is sizing. Manufactured according to GOST 8732-78.
- Seamless cold worked. As well as, a hot-rolled billet uses for Aluminized steel, which goes through the stages of cold rolling, forging and drawing. The current standard is GOST 8734-75.
- Electro welded straight seam. Thirdly, the strips process by pressing molding and then straight seams form by electric arc welding. Requirements in GOST 10704-91.
- Electro welded spiral.The processes steel strip forms on the machines to the billet. Welding of the inner and outer seam, processing carries out. Produce in accordance with GOST 8696-74.
For each method, a manufacturing technology compiles. Seamless products with a large wall thickness (from 3.5 mm), which increases the maximum allowable pressure in the system. Moreover, the method of manufacturing electric-welded pipes makes it possible to form a wall with a thickness of 1.5 mm.
Types of round pipes
Eventually, the choice of Aluminized steel depends on operational requirements and technical characteristics. The latter include diameter (outer, inner), wall thickness, and length. Further, Properties depend on the class, materials of manufacture, additional processing.
By diameter and wall thickness
Furthermore, when we are designing, the internal pressure in the pipeline (nominal, maximum), the speed of the working medium, and the degree of corrosive wear are taken into account. The main factor is throughput. This is the volume of liquid (air, gas) that passes through the highway in a certain time.
In addition, water and gas pipes VGP belong to a separate category. In fact, the reason is that they use for arranging utility networks (gas and water pipes), Manufacture by electro fusion. For them, GOST 3262-75 applies, which lists the standard dimensions of products.
Aluminized steel Performance classification
Subsequently, to select according to working conditions and require qualities, a general classification of steel round pipes develops. With its help, a primary analysis carries out, but for the preparation of project documentation and exact requirements, further, it is necessary to use GOST and the actual characteristics of specific products.
Description of classes:
- General purpose of Aluminized steel uses to create structures, irrigation systems. Are parts of the schemes of local distribution of gas, liquids?
- Form oil and gas pipelines of low or high pressure.
- The mains operate under strong external thermal influence; eventually, they are often installed in boilers, furnaces.
- these are drilling, casing pipes of gas and oil fields.
- Aluminized steel Uses to create load-bearing metal structures.
- they make blanks for parts - cylinders, shafts, bearing rings.
Moreover, for the manufacture of round pipes of class 1 and 2, alloy steel uses. The rest make from special grades of metal, taking into account operating conditions. Additionally, the surface subjects to heat treatment, covered with anti-corrosion compounds.
Main characteristics
In addition, to the diameter and wall thickness, when choosing, it is necessary to take into account the maximum allowable pressure inside the pipelines, the temperature of the working fluid and the external environment. To expand the possibility of using the last parameter, external insulation installs: bituminous mastic, "shells" of polyurethane foam, extruded polyethylene.
The diameter of the conditional passage is necessary to calculate the volume of supply of the working medium in the line. This is the internal section of a round pipe, rounded down. Additionally, surface roughness is taken into account, which affects the flow rate.
Aluminized steel Features description:
- Wall thickness. There are extra-thin-walled, thin-walled, normal, thick-walled, and extra-thick-walled.
- Aluminized steel Measured are made according to standard sizes, multiples are made taking into account subsequent cutting with an allowance of 5 mm. Random length not regulates.
- Accuracy class. As well as, it is depends on the presence of machined edges (deburring), for electric-welded round pipes, ovality are taken into account. Normal tolerances are ± 2.5-4 mm, increased tolerances are ± 1.6 + 3.5 mm. Depends on outer diameter.
A separate category of characteristics is the presence of a galvanized protective layer. The coating thickness for the electroplating method is 10-30 microns. With hot galvanizing, it increases to 30-100 microns.
Applications depending on the production technology
Lastly, the main area of use is the creation of systems for pumping various substances (water, oil products, gas). The choice influences by manufacturing technology and Aluminized steel grades. Additional processing expands the scope, but affects the cost. Therefore, it is important to create performance requirements for round steel pipes.
Overview of applications:
- Seamless. Pumping of oil products or similar compositions under high pressure.
- Welded. Creation of highways for heat and water supply, manufacturing of parts of metal structures.
- Water and gas pipelines.Distribution engineering networks for hot and cold water transportation, gas supply.
In addition, special requirements impose on pipes from which parts with extreme operating conditions will be made. It can be motor pistons, cylinders. The blanks need to be further processed.
Advantages and disadvantages
The main advantage of Aluminized steel round pipes is mechanical strength. Therefore, they use in high pressure lines. Even with short-term critical indicators, the walls of the products not deform. To maintain reliability, special couplings install at the joints of the nozzles.
Additional benefits:
- minimum coefficient of thermal expansion;
- the material is airtight, there is no mixing of the working medium in the system;
- the ability to choose in size, wall thickness, manufacturing method;
- Aluminized steelrelatively low cost.
Furthermore, the main disadvantage is susceptibility to rust. But to solve it, additional processing technologies use, external protective layers provide. During the design, the large mass of steel pipes is taken into account. To create highways, additional attachment points and supports need.
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