Gauge welded steel pipes is huge, which allows them to find application in various fields. For the transport of fluids and gases in industry and the home are used in most cases steel pipes. Of them can be fitted open or closed conduits, they can act as protective covers of cable lines, etc.
weight table welded steel pipes, presented in the article, it allows a regular user to navigate in the price of the necessary material.
of steel pipes can be found in household, industrial construction, aircraft construction, mechanical engineering and shipbuilding. Such widespread this building material was due to its high strength properties and at the same time a good ductility. However, corrosion resistance and cold resistance of these products impose severe restrictions on their field of application.
Classification
steel division production takes place according to the following criteria:
- Linear dimensions and cross-sectional view;
- Manufacturing technology;
- The presence of the protective coating.
Linear size and type of section you can divide as follows:
- Round, square, polygonal oval cross section;
- The magnitude of the outer diameter:
- capillaries (0.3 to 4.8 mm);
- a small diameter (5 to 102 mm);
- average diameter (from 102 to 426 mm).
- The ratio of outer diameter and wall thickness:
- osobotolstostennye;
- thick;
- normal;
- Thin-wall;
- extra thin-walled.
- Length:
- off-gage;
- dimensional;
- fold.
- Accuracy class manufacturing:
- cutting edges, deburring, chamfering application - 1st banks;
- pruning - 2nd class.
According to the manufacturing technology:
- electrically welded;
- Electrically spiral seam;
- weldless.
The protective coating on the surface:
- galvanized;
- chrome;
- nickel plating;
- a polymeric coating;
- coating the cement-bitumen, etc.
making
As noted in the previous section, products can be manufactured by two techniques: using welding and by means of deformation (drawing).
Manufacturing by welding
Welded pipes are manufactured by bending the sheet material into a profile (circle, square, oval, etc.), followed by welding in an inert gas tungsten arc or by high frequency currents. The welding seam can be straight or spiral, all depends on the bending technology, curling the steel sheet and the diameter of the future product. Various steel pipes can be of different diameters so.
seamless pipes
Seamless line may be made of steel rod by drilling holes in it, as well as by casting, hot or cold deformation. The first and the second technique (drilling, injection) preparation used infrequently. Typically, drilling method and molding products obtained for special purposes (gun barrels, heat exchangers). Basically seamless products obtained deformation.
hot deformation method is as follows: a cylindrical steel billet is heated in a furnace, followed by drawing-metal blank is converted into a product cylinder, and after it was adjusted to rollers. On rollers adjustments are diameter and straightness of products.
cold deforming method differs from the preceding only in that the treatment of the steel products is carried out on rollers in a cold state. It should be noted that the thick lines are made only by the methods of deformation, and they do not come in electrofusion.
Advantages and disadvantages
Pipes made of steel, as well as any product has its pros and cons.
Advantages:
- a guaranteed lifespan of about 15 years;
- Operating Temperature - 130 degrees;
- operating pressure - up to 30 atm .;
- fire resistance;
- resistant to mechanical damage;
- best material for heating pipes.
Disadvantages:
- low corrosion resistance;
- large mass;
- installation of a relatively complex compared to modern types of products (bi-metallic, plastic);
- unsightly appearance, needed painting.
Gauge steel pipes
The highest sale in the pipe segment recorded for medium and large diameter - from 159 to 1420 mm. All other diameters are sold in lesser amounts. This-is due primarily to the fact that the large-diameter tubular products used for laying of main pipelines transporting liquids or gases. In addition, seamless diameter of 426 mm Russian production is unlikely to happen to find on the market, as the technology of their production only began to explore. However, gage welded steel pipes closes all positions diameters. Products with spiral welds may have a diameter of over 1,420 mm, but at the same time and at least 159 mm. For longitudinally welded products - a maximum diametric size of 1420 mm, and the minimum - 8 mm. The difference in diameters electrofusion pipe (straight and spiral) associated with different production technologies.
Furthermore diameter, the second most important in linear dimension is the thickness of the steel pipe wall. For the production of a cross-sectional thickness of the wall may be different. For example, for a diameter of 530 mm steel thickness will be 5-24 mm, and for a diameter of 1020 mm - 8-32 mm thick steel.
It should be noted that the wall thickness (particularly true for large diameters) may vary according to GOST a wide range. In particular, the amount to ± 0,8 mm for the deviation meter diameter steel thickness.
In turn, the wall thickness depends on the weight, and it determines the price of the products. This is because, electrically welded steel pipes or spiral implemented regardless of gauge by weight. Of course, the sale of no material to be weighed, and their weight is calculated theoretically. Calculation of the weight of steel pipe is carried out as follows: weight of 1 lm = 0,02466 × S × (D-S) (Figure 5). In practice, the purchase is as follows: the buyer checks the wall thickness, more weight is computed per meter and is multiplied by the total planed product.
In the case of electric pipe length is not specified, then it is likely to be about 11 meters. Seamless pipes GOST may have a length 4-12,5 meters. Were in operation of the product is cleaned and cut to length, so their linear dimensions necessary to monitor more thoroughly.
Later in the article, see the mass of the most common electric products of different diameters. Certain intermediate diameters in Table omitted, however, their mass is not substantially different from adjacent items.
Weight electrowelded steel pipe
Weight electrowelded steel pipe is shown in Table 1.
Approximate cost of distributing products of a small section is shown in Table 2.
Specific applications
- Pipes Direct weld firmly taken place as the main material for the lines with moderate pressure. They are also often used to create steel structures.
- Products with spiral weld used for the construction of water supply lines, heating mains, gas pipelines, etc.
- Seamless pipes:
- Hot used for very critical highways. Especially where unacceptable slightest leakage, for example, the chemical industry. they also firmly taken the place where you need to withstand enormous pressure. B is primarily due to the fact that these pipes have a very large wall thickness which does not stress concentrator in the form of a weld.
- Cold-applied in places with very high wall strength required is not very large weight of the product. In particular, these pipe walls thinner than that of hot, but on the strength properties are not inferior to them. They are in demand in the chemical industry, shipbuilding, aviation, oil and gas industry, ie in very critical areas.
For domestic use is open to all kinds of pipes, but in most cases, longitudinal welded - for heating and weldless - for water and gas pipelines.
Based on all the above can be concluded that the seamless steel electric or hot rolled / cold rolled tube will still long the main material for the construction of the main buildings, as well as predominating in the construction of heating systems, domestic nature. This is supported by the high strength properties of steel products, the relative ease of installation, durability, and low cost. In addition, a wide assortment of steel pipes makes them virtually irreplaceable in most cases.
