Inside buildings, the piping layout has a branched structure into many sections, and on each of them there are numerous turns in the direction of movement. The scheme of the heating or water supply system of an apartment building turns out to be quite complex and its installation requires the use of special connecting parts. In order to make a ninety-degree turn in the corner of the room, so-called straight bends are often used, and for connecting radiators, registers or convectors, couplings in combination with couplings and lock nuts are most often used. Not every type of tubular black metal is suitable for the manufacture of such elements, since most of them have significant drawbacks for an effective solution to such a problem. The best material for achieving this goal is round cold rolled steel pipe, produced in large quantities annually by Ukrainian metallurgical plants.
This is due to the presence of a whole set of specific properties in this type of rolled products, which are absent in others. To understand the difference, it is reasonable to consider their influence separately:
- A solid wall ensures uniform distribution of deformations when applying forces in any direction, therefore, unlike those with welded seams, it maintains integrity when bending at large angles. Often, to obtain a bend, neither preheating is required to increase the plasticity of the metal, nor filling the internal space with dry sand. With small diameters, the pipe can be bent directly at the installation site manually without special devices and bulky pipe benders after heating in the right place, which reduces the number of welded seams required for installation and increases its speed.
- The large wall thickness allows cutting of traditionally measured in inch pipe threads on the internal or external surface of blanks obtained from this material without significantly weakening the ability to withstand high internal pressure of the pumped liquid or gas. Thus manufactured couplings, couplings and locknuts facilitate rapid installation in the general scheme of various user equipment without the risk of leakage due to thinning of the walls.
- The structural steel used as the raw material for the production of the described products lends itself very well to gas or manual arc welding.
According to the listed features, except for the last one, it is close to the one described water and gas steel pipe, the wall of which is formed from a spirally twisted strip, the edges of which are welded to each other. Since its cost is lower, it is sometimes used as a substitute for connections that do not require high reliability.
Possibilities of using round cold-rolled steel pipes for other purposes and their analogues
Of course, round cold-rolled steel pipes are also suitable for creating straight sections of pipelines, but due to their high cost, this is not always economically feasible. For solving simple problems, it is more profitable to use less reliable but cheaper analogues.
Round electric welded steel pipe
For sections of water supply, heating and gas supply systems that do not have turns, it is quite reasonable to use round electric welded steel pipes. Although they are not resistant to bending, since they diverge quite easily along the longitudinal seam when deformed, but due to the simplicity of the technological method of production from flat strips of black rolled metal, they are included in the group of the cheapest. When implementing a large project, their use instead of expensive analogues leads to significant savings in budget funds.
Seamless profile steel pipe
Having a square or rectangular cross-section seamless profile steel pipe is not suitable for bending, since it has impressive rigidity in any of the directions perpendicular to the axis, and even more so for thread cutting. The ratio of the useful area of the working medium to the perimeter is less than that of round analogs, so to ensure the same performance, you will have to spend more money on purchasing material. However, if it is necessary to tightly fill a small gap allocated for the passage of pipelines, their use can bring significant benefits. Also, the increased surface area is useful in the design and creation of heat exchangers for industrial boilers and boilers.