GOST 32931-2015 Steel profile pipes for metal structures. Specifications

Steel profile pipes, which are a significant part of the rolled metal market, as well as other materials for creating load-bearing structures, are manufactured in strict accordance with the requirements of the relevant GOSTs. For example, a profile pipe GOST 30245-2003 is standardized as a bent welded closed product with a square or rectangular profile used as an element for the construction of steel building structures.

What are the requirements of the above mentioned GOST, as well as other regulatory documents related to profile pipes, we will consider in this article.

List of GOSTs related to profile pipes

Manufacturing algorithm

The production process of profiled square or rectangular pipes consists of the following steps:

1. Unwinding a roll of steel strip.
2. Cutting segments to the required length and width. For this purpose, a special cutting installation is used.
3. Welding the cut strip into a strip.
4. Winding the welded tape onto a drum that constantly rotates. This technological operation provides for the continuous rolling of profiles.
5. Providing the forming mill with welded strip. At the same time, a round (in cross-section) blank is formed by rollers. This process will continue until the end of the tape on the drum. At this stage, the workpiece practically does not heat up (a cold-rolled profile pipe is obtained). Although, an option with heat treatment is also possible.
6. Transfer of workpieces with open seams to the welding plant.
7. Welding of edges with high-frequency currents with simultaneous squeezing of the workpiece along its entire length by rollers.
8. Cooling process using emulsion compositions.

Theoretical mass of steel rectangular pipes and number of meters per ton GOST 8645-68

Practical use

Various types of frames, temporary and permanent greenhouses, hangars, billboards, elements of furniture products - for the production of these, as well as other metal structures of various sizes and types, rectangular or square profile pipes are used. A water-gas pipe is not at all suitable for such work, just as no one uses a profile pipe for laying gas or water pipes.

The scope of use of this rental is quite wide.

Most often in everyday life and the national economy we deal with:

• main profiles. Such corrugated pipes serve as excellent support segments, which are used in large-sized pipelines in areas with frequent pressure drops. Typically, such highway elements are produced according to special specifications and individual orders;
• classic profile pipes. They are used in the construction of scaffolding for construction sites and pipelines. They are an ideal option for protecting cables; you cannot do without them when building fences, gates, wickets, and irrigation systems;
• rolled metal profiles with increased resistance to chemical environments. Most often, they are used in pharmaceutical, chemical, and food plants;
• mechanical engineering profiles. Bearings, cylinders, shafts, and pistons for the engineering industry are produced from such rolled metal.

Introduction

This standard was developed on the basis of interstate standards GOST 13663, GOST 8639, GOST 8642, GOST 8644 and GOST 8645, as well as a generalization of domestic and foreign experience in the use of pipes.

Pipes manufactured according to GOST 13663, GOST 8639, GOST 8642, GOST 8644 and GOST 8645 have the same scope of application as pipes for metal structures. Therefore, in this standard, developed on the basis of the mentioned standards, the requirements for these pipes are combined.

Compared to GOST 13663, GOST 8639, GOST 8642, GOST 8644 and GOST 8645 in this standard:

— classification of pipes by strength classes has been introduced;

— the range of pipes has been expanded: by profile size - up to 500 mm, by wall thickness - up to 22.0 mm, by profile shape - with the inclusion of round pipes;

— two pipe manufacturing precisions have been established: normal and increased;

Preface

The goals and principles, the basic procedure for work on interstate standardization are established by GOST 1.0-92 “Interstate standardization system. Basic provisions" and GOST 1.2-2009 "Interstate standardization system. Interstate standards, rules and recommendations for interstate standardization. Rules for development, adoption, application, updating and cancellation"

Standard information

1 PREPARED by the Technical Committee for Standardization TC 357 “Steel and cast iron pipes and cylinders”. Open Joint Stock Company "Russian Research Institute of Pipe Industry" (JSC "RosNITI")

2 INTRODUCED by the Technical Committee for Standardization TC 357 “Steel and cast iron pipes and cylinders”

3 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes dated June 18, 2015 No. 47)

Properties

Like any metal products, cold-rolled profile pipes have their pros and cons.

Advantages

The GOST profile cold-rolled pipe is different:

• strength, characterized by flexibility and lightness;
• resistance to heavy loads, which is ensured by the presence of corner stiffeners;
• simplicity and ease of installation;
• the ability to construct structures of various architectural and design types;
• resistance to possible damage;
• low cost in comparison with other types of fittings;
• high resistance to temperature changes;
• aesthetics;
• efficiency.

Using seamless cold-rolled pipes, complex, high, reliable structures can be easily and quickly erected.

From a logistics point of view, profile-type products are the best option for transportation, loading, unloading and warehousing.

Flaws

The main and probably the only significant drawback of profile-type pipes is corrosion, which all metal products are subject to. This “minus” can disrupt the performance characteristics of professional pipes. But in this case, this problem can be solved by using galvanizing technology, due to which the service life of products increases significantly.

Rectangular

Rectangular profile pipes are produced with a range in accordance with GOST 8645-68. The length and maximum deviations in size correspond to GOST 8639-82.

Profile pipes of this section are most often used in construction as metal beams. Four stiffening ribs, low specific gravity and high bending strength allow them to withstand increased loads. Profile rectangular steel pipes are fastened by electric arc welding. In addition to high strength, such products are more economical (up to 25% compared to round ones) and easier to install, allowing the creation of more complex engineering structures. Fits well on flat surfaces. They are also used to create durable frames in furniture production, the automotive industry, for the construction of durable structures, supports, where the low weight of the profile is a decisive factor, for example, in outdoor advertising.

Dimensions:

• width: 10, 20, 25, 30, 35, 40, 42, 45, 50, 60, 70, 80, 90, 100, 110, 120, 140, 150, 180 mm;
• height: 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 100, 120, 150 mm;
• thickness: 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 8, 9, 10, 12 mm.

The most popular sizes of this profile are 40×80 and 40×100 mm; rectangular profiles of large diameter are also available.

An example of the designation of a rectangular profile pipe 40 mm x 25 mm x 3 mm, wall thickness 3.0 mm, length multiple of 1250 mm, made of steel 10, with a chemical composition according to group B (GOST 13663-86):