Cold-deformed seamless steel pipes GOST 8734 78: characteristics and purpose

Cold-deformed seamless steel pipes GOST 8734 75 and 78 are types of metal pipes. They are used in almost all sectors of the national economy, as well as in the field of room decoration and furniture industry. Having many advantages, they do not lose their relevance today. However, before using them for your own purposes, you should familiarize yourself with all the features of this product.

Seamless pipes have higher strength than welded pipes and are used in many areas of construction

Main characteristics

Today, the plumbing equipment market can offer a lot of products that differ in individual technical characteristics, material, diameter, overall parameters, purpose and other criteria. Since the last century, metal has been a popular material for communication water supply and sewerage systems. Today it is also used for the transportation and supply of gas, oil, chemicals, etc. Despite the fact that relatively recently steel products began to receive significant competition from plastic ones, the former still do not lose their relevance, because in some cases they are simply irreplaceable.

Cold-deformed seamless steel pipes GOST 8734 78 are made from a special steel composition, which ensures that they meet the necessary quality standards and creates certain advantages over products made from other materials.

This pipe has different characteristics and technical features depending on its purpose, dimensions and other parameters.

Thin-walled steel electric-welded pipes

One of the areas of work is the sale of certified thin-walled electric-welded steel pipes directly from the manufacturing plant. Such products are distinguished by high technical characteristics and reasonable prices.

Electric-welded thin-walled steel pipes can be used in various fields:

  • as grounding;
  • in the form of posts for fences, fences (often a rectangular or square thin-walled pipe);
  • for internal systems of various mechanisms and machines;
  • during construction, in the case of erecting metal structures (for example, mobile base station towers, power lines);
  • when installing pipelines with low pressure (water supply systems, gas pipelines);
  • in the production of furniture and tents.

Features of operation of thin-walled pipes

Electro-welded steel products of small thickness are the optimal material for the installation of modern lightweight structures, both domestic and industrial. Steel grades (08, 10, 20, St1, St3, St2) used in the production of products comply with the requirements of GOST 380-2005 and guarantee strength and long service life.

The plasticity and flexibility of thin-walled steel pipes makes it possible to form transport systems of complex configurations and reduce hydraulic resistance. It is worth remembering that connections of such structures should preferably be threaded.

You can only use welding work if you have the proper experience and high professionalism of the specialist, because it is quite easy to burn through thin metal.

Electric-welded steel pipes, supplied by , are made of low-alloy and high-carbon steel. The most popular products are round, but they can also be oval, square, or rectangular.

Advantages of steel pipes

These seamless steel products have many positive qualities that cannot be ignored when choosing equipment.

Seamless pipes are the basis of pipelines for various purposes - for supplying water, gas, oil

Among them:

  • versatility. Pipes are used in almost all areas of everyday and professional human activity; pipelines made from them can be used in various types of buildings for transporting almost any liquids and gaseous substances;
  • absolute tightness. Such equipment is used for laying closed communications that require protection from airing. Cold formed systems provide maximum protection against oxygen and gases;
  • extensive assortment. The modern market for plumbing equipment can offer a huge number of varieties of pipes, differing in manufacturing method, length, diameter, purpose and technical characteristics;
  • strength. Metal is a hard and dense material, it is not subject to expansion as a result of working with hot substances, that is, parts are resistant to damage of a mechanical, biological and chemical nature. In addition, standards No. 8734 75 and 8733 74 suggest some of their varieties that can work with aggressive substances;
  • ability to withstand temperature changes and heavy loads. Possessing a high melting point and due to the dense structure of the material, such pipes, if, of course, their parameters comply with GOST 8734 78 and 75, function normally even in cold weather. Due to the fact that these products are seamless, they can better withstand workload and increased pressure, since they do not have weak points - joints.

The parameters of the pipes are indicated on their outside, this allows you to determine their purpose and compliance with the conditions of the future highway

Helpful advice! Whatever type you are interested in, make sure that the product complies with GOST standards (8734 75 for cold-formed and 87 for hot-formed). You can distinguish high-quality steel seamless cold-deformed pipes produced in accordance with GOST 8734 75 (as well as 78, 78, 87) by their appearance and markings.

GOST 8734-75 Cold-deformed seamless steel pipes. Assortment

STATE STANDARD OF THE USSR UNION

COLD-FORMED SEAMLESS STEEL PIPES

Assortment

GOST 8734-75

STATE STANDARD OF THE USSR UNION

COLD-FORMED SEAMLESS STEEL PIPES

Assortment

Seamless steel tubes cold deformed. Range

GOST 8734-75

Date of introduction 01/01/77

la. This standard fully complies with ST SEV 1483-78.

(Introduced additionally, Amendment No. 2).

1. The outer diameter, wall thickness and theoretical weight of the pipes must correspond to those indicated in the table. 1.

(Changed edition, Amendment No. 1).

2. Depending on the ratio of the outer diameter ( D

n) to wall thickness (
s
) pipes are divided into:

extra-thin-walled at D

n
/ s
more than 40 and pipes with a diameter of 20 mm or less with a wall of 0.5 mm or less;

thin-walled at D

n
/ s
from 12.5 to 40 and pipes with a diameter of 20 mm or less with a wall of 1.5 mm;

thick-walled at D

n
/ s
from 6 to 12.5;

extra thick walled at D

n
/ s
less than 6.

3. According to the length of the pipe, the following should be made:

unmeasured length from 1.5 to 11.5 m;

measured length from 4.5 to 9 m with maximum length deviations of +10 mm; By order of foreign trade organizations, pipes are manufactured in measured lengths from 4 to 9 m with maximum length deviations of +10 mm;

length, a multiple of the measured length, from 1.5 to 9 m with an allowance for each cut of 5 mm (unless another allowance is specified in the order) and with maximum deviations for the total length not exceeding those specified for pipes of the measured length.

(Changed edition, Amendment No. 3).

4. Maximum deviations in the outer diameter and wall thickness of the pipes must not exceed those indicated in the table. 2.

5 . By agreement between the manufacturer and the consumer, pipes can be manufactured with combined maximum deviations, for example, in outer diameter - increased accuracy according to GOST 9567, and in wall thickness - normal accuracy, or with a one-sided dimensional tolerance. The value of the one-sided tolerance should not exceed the sum of the two-sided maximum deviations given in table. 2. In this case, the value of the theoretical mass of 1 m of pipes is calculated from the arithmetic mean value of the sum of the plus and minus maximum deviations given in table. 2.

Table 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
0,3 0,4 0,5 0,6 0,8 1,0 1,2 1,4 1,5 1,6 1,8 2,0 2,2 2,5
Extra-thin-walled Thin-walled Thin-walled Thick-walled Extra thick walled
5 0,0348 0,0454 0,0555 0,0651 0,0829 0,0986 0,112 0,124 0,129
6 0,0422 0,0552 0,0678 0,0799 0,103 0,123 0,142 0,159 0,166 0,174 0,186 0,197
7 0,0496 0,0651 0,0801 0,0947 0,122 0,148 0,172 0,193 0,203 0,213 0,231 0,247 0,260 0,277
8 0,0570 0,0750 0,0925 0,110 0,142 0,173 0,201 0,228 0,240 0,253 0,275 0,296 0,315 0,339
9 0,0644 0,0847 0,105 0,124 0,162 0,197 0,231 0,262 0,277 0,292 0,320 0,345 0,369 0,401
10 0,0718 0,0947 0,117 0,139 0,182 0,222 0,260 0,297 0,314 0,332 0,364 0,395 0,426 0,462
11 0,0792 0,105 0,129 0,154 0,201 0,247 0,290 0,331 0,351 0,371 0,408 0,444 0,477 0,524
12 0,0866 0,114 0,142 0,169 0,221 0,271 0,320 0,366 0,388 0,410 0,453 0,493 0,532 0,586
13 0,0940 0,124 0,154 0,184 0,241 0,296 0,349 0,401 0,425 0,450 0,497 0,543 0,586 0,647
14 0,101 0,134 0,166 0,198 0,260 0,321 0,379 0,435 0,462 0,489 0,542 0,592 0,640 0,709
15 0,109 0,144 0,179 0,213 0,280 0,345 0,408 0,470 0,499 0,529 0,586 0,641 0,694 0,771
16 0,116 0,154 0,191 0,228 0,300 0,370 0,438 0,504 0,536 0,568 0,630 0,691 0,749 0,832
17 0,124 0,164 0,203 0,243 0,320 0,395 0,468 0,539 0,573 0,608 0,675 0,740 0,803 0,894
18 0,131 0,174 0,216 0,258 0,339 0,419 0,497 0,573 0,610 0,647 0,719 0,789 0,857 0,956
19 0,138 0,183 0,228 0,272 0,359 0,444 0,527 0,608 0,647 0,687 0,764 0,838 0,911 1,017
20 0,146 0,193 0,240 0,287 0,379 0,469 0,556 0,642 0,684 0,726 0,808 0,888 0,966 1,079
21 0,203 0,253 0,302 0,399 0,493 0,586 0,677 0,721 0,765 0,852 0,937 1,020 1,141
22 0,213 0,265 0,317 0,418 0,518 0,616 0,711 0,758 0,805 0,897 0,986 1,074 1,202
23 0,223 0,277 0,331 0,438 0,543 0,645 0,746 0,795 0,844 0,941 1,036 1,129 1,264
24 0,233 0,290 0,346 0,458 0,567 0,675 0,780 0,832 0,884 0,985 1,085 1,183 1,326
25 0,243 0,302 0,361 0,477 0,592 0,704 0,815 0,869 0,923 1,030 1,134 1,237 1,387
26 0,253 0,314 0,376 0,497 0,617 0,734 0,849 0,906 0,963 1,074 1,184 1,291 1,449
27 0,262 0,327 0,391 0,517 0,641 0,764 0,884 0,943 1,002 1,119 1,233 1,346 1,511
28 0,272 0,339 0,405 0,537 0,666 0,793 0,918 0,980 1,042 1,163 1,282 1,400 1,572
30 0,292 0,364 0,435 0,576 0,715 0,852 0,987 1,054 1,121 1,252 1,381 1,508 1,695
32 0,312 0,388 0,465 0,616 0,764 0,911 1,056 1,128 1,200 1,341 1,480 1,617 1,819
34 0,331 0,413 0,494 0,655 0,814 0,971 1,126 1,202 1,278 1,429 1,578 1,725 1,942
35 0,341 0,425 0,509 0,675 0,838 1,000 1,160 1,239 1,318 1,474 1,628 1,780 2,004
36 0,351 0,438 0,524 0,694 0,863 1,030 1,195 1,276 1,357 1,518 1,677 1,834 2,065
38 0,371 0,462 0,553 0,734 0,912 1,089 1,264 1,350 1,436 1,607 1,776 1,942 2,189
40 0,391 0,487 0,583 0,773 0,962 1,148 1,333 1,424 1,515 1,696 1,874 2,051 2,312

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
2,8 3,0 3,2 3,5 4,0 4,5 5,0 5,5 6,0 6,5 7,0
Extra thick walled
5
6
7
8
9
10 0,497 0,518 0,537 0,561
11 0,566 0,592 0,616 0,647
12 0,635 0,666 0,694 0,734
13 0,704 0,740 0,773 0,820 0,888
14 0,773 0,814 0,852 0,906 0,986
15 0,842 0,888 0,931 0,993 1,085
16 0,911 0,962 1,010 1,079 1,184 1,276 1,356
17 0,981 1,036 1,089 1,165 1,282 1,387 1,480
18 1,050 1,110 1,168 1,252 1,381 1,498 1,603
19 1,119 1,184 1,247 1,338 1,480 1,609 1,726
20 1,188 1,258 1,326 1,424 1,578 1,720 1,850 1,967 2,072
21 1,257 1,332 1,405 1,511 1,677 1,831 1,973 2,102 2,220
22 1,326 1,406 1,484 1,597 1,776 1,942 2,096 2,238 2,368
23 1,395 1,480 1,563 1,683 1,874 2,053 2,220 2,374 2,515
24 1,464 1,554 1,641 1,769 1,973 2,164 2,343 2,509 2,663 2,805
25 1,533 1,628 1,720 1,856 2,072 2,275 2,466 2,645 2,811 2,965 3,107
26 1,602 1,702 1,800 1,942 2,170 2,386 2,589 2,781 2,959 3,125 3,280
27 1,671 1,776 1,878 2,028 2,269 2,497 2,713 2,916 3,107 3,286 3,453
28 1,740 1,850 1,957 2,115 2,368 2,608 2,836 3,052 3,255 3,446 3,625
30 1,878 1,998 2,115 2,287 2,565 2,830 3,083 3,323 3,551 3,767 3,971
32 2,016 2,146 2,273 2,460 2,762 3,052 3,329 3,594 3,847 4,087 4,316
34 2,154 2,294 2,430 2,633 2,959 3,274 3,576 3,866 4,143 4,408 4,661
35 2,223 2,367 2,510 2,719 3,058 3,385 3,699 4,001 4,291 4,568 4,834
36 2,293 2,441 2,588 2,805 3,157 3,496 3,822 4,137 4,439 4,728 5,006
38 2,431 2,589 2,746 2,978 3,354 3,718 4,069 4,408 4,735 5,049 5,352
40 2,569 2,737 2,904 3,150 3,551 3,940 4,316 4,680 5,031 5,369 5,697

Continuation of the table.
1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
7,5 8,0 8,5 9,0 9,5 10 11 12 14 16 18 20 22 24
Extra thick walled
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
30 4,162 4,340
32 4,531 4,735
34 4,901 5,129
35 5,086 5,327
36 5,271 5,524
38 5,641 5,919 6,184 6,437
40 6,011 6,313 6,603 6,881

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
0,3 0,4 0,5 0,6 0,8 1,0 1,2 1,4 1,5 1,6 1,8 2,0 2,2 2,5
Extra-thin-walled Thin-walled
42 1,011 1,207 1,402 1,498 1,594 1,785 1,973 2,159 2,435
45 1,085 1,296 1,505 1,609 1,712 1,918 2,121 2,322 2,620
48 1,159 1,385 1,609 1,720 1,831 2,051 2,269 2,435 2,805
50 1,208 1,444 1,678 1,794 1,910 2,140 2,368 2,594 2,929
51 1,233 1,474 1,712 1,831 1,949 2,184 2,417 2,648 2,990
53 1,282 1,533 1,782 1,905 2,028 2,273 2,515 2,756 3,114
54 1,307 1,563 1,816 1,942 2,068 2,317 2,565 2,810 3,175
56 1,356 1,622 1,885 2,016 2,147 2,406 2,663 2,919 3,298
57 1,381 1,651 1,920 2,053 2,186 2,450 2,713 2,973 3,360
60 1,455 1,740 2,023 2,164 2,304 2,584 2,861 3,136 3,545
63 1,529 1,829 2,127 2,275 2,423 2,717 3,009 3,499 3,730
65 1,578 1,888 2,196 2,349 2,502 2,806 3,107 3,407 3,853
68 1,652 1,977 2,299 2,460 2,620 2,939 3,255 3,570 4,038
70 1,702 2,036 2,368 2,534 2,699 3,027 3,354 3,673 4,162
73 1,776 2,125 2,472 2,645 2,817 3,161 3,502 3,841 4,347
75 1,825 2,184 2,541 2,719 2,896 3,249 3,601 3,930 4,470
76 1,850 2,214 2,576 2,756 2,936 3,294 3,650 4,004 4,532
80 2,331 2,714 2,904 3,094 3,471 3,847 4,221 4,778
83 2,420 2,817 3,015 3,212 3,605 3,995 4,383 4,963
85 2,480 2,886 3,089 3,291 3,693 4,094 4,492 5,086
89 2,598 3,024 3,237 3,449 3,871 4,291 4,709 5,333
90 2,628 3,059 3,274 3,488 3,915 4,340 4,763 5,395
95 2,776 3,232 3,459 3,685 4,137 4,587 5,034 5,703
100 3,644 3,883 4,359 4,834 5,306 6,011
102 3,718 3,962 4,448 4,933 5,414 6,135
108 3,940 4,198 4,714 5,228 5,740 6,504
110 4,014 4,277 4,803 5,327 5,849 6,628
120 4,384 4,672 5,247 5,820 6,391 7,244
130 4,754 5,066 5,691 6,313 6,934 7,861
140 5,461 5,135 6,807 7,476 8,477
150 6,579 7,300 8,019 9,094
160 7,793 8,561 9,710
170 8,286 9,104 10,327

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
2,8 3,0 3,2 3,5 4,0 4,5 5,0 5,5 6,0 6,5 7,0
Thin-walled Thick-walled
42 2,707 2,885 3,062 3,323 3,749 4,162 4,562 4,951 5,327 5,690 6,042
45 2,914 3,107 3,299 3,582 4,044 4,495 4,932 5,358 5,771 6,171 6,560
48 3,121 3,329 3,535 3,841 4,340 4,827 5,302 5,765 6,215 6,652 7,078
50 3,259 3,477 3,693 4,014 4,538 5,049 5,549 6,036 6,511 6,972 7,423
51 3,328 3,551 3,772 4,100 4,636 5,160 5,672 6,172 6,659 7,132 7,596
53 3,466 3,699 3,930 4,273 4,834 5,382 5,919 6,443 6,955 7,453 7,941
54 3,535 3,773 4,009 4,359 4,932 5,493 6,042 6,578 7,103 7,613 8,114
56 3,674 3,921 4,167 4,532 5,130 5,715 6,289 6,850 7,398 7,934 8,459
57 3,743 3,995 4,246 4,618 5,228 5,826 6,412 6,985 7,546 8,095 8,632
60 3,950 4,217 4,482 4,877 5,524 6,159 6,782 7,392 7,990 8,575 9,149
63 4,157 4,439 4,719 5,136 5,820 6,492 7,152 7,799 8,434 9,056 9,667
65 4,295 4,587 4,877 5,308 6,017 6,714 7,398 8,070 8,730 9,377 10,013
68 4,502 4,809 5,113 5,567 6,313 7,047 7,768 8,477 9,174 9,857 10,530
70 4,640 4,957 5,271 5,740 6,511 7,269 8,015 8,749 9,470 10,178 10,876
73 4,847 5,179 5,508 5,999 6,807 7,602 8,385 9,156 9,914 10,659 11,394
75 4,986 5,327 5,666 6,172 7,004 7,824 8,631 9,427 10,210 10,980 11,739
76 5,055 5,401 5,745 6,258 7,103 7,935 8,755 9,562 10,358 11,140 11,911
80 5,331 5,697 6,060 6,603 7,497 8,379 9,248 10,105 10,950 11,781 12,602
83 5,538 5,919 6,298 6,862 7,793 8,712 9,618 10,512 11,394 12,263 13,120
85 5,676 6,067 6,455 7,035 7,990 8,934 9,865 10,783 11,690 12,584 13,465
89 5,952 6,363 6,771 7,380 8,385 9,378 10,358 11,326 12,281 13,225 14,156
90 6,021 6,437 6,850 7,466 8,484 9,489 10,481 11,461 12,429 13,385 14,328
95 6,367 6,867 7,244 7,898 8,977 10,043 11,098 12,140 13,169 14,187 15,191
100 6,712 7,176 7,639 8,329 9,470 10,598 11,714 12,818 13,909 14,988 16,055
102 6,850 7,324 7,797 8,502 9,667 10,820 11,961 13,089 14,205 15,308 16,400
108 7,264 7,768 8,270 9,020 10,259 11,486 12,701 13,903 15,093 16,269 17,436
110 7,402 7,916 9,428 9,193 10,456 11,708 12,947 14,174 15,389 16,590 17,781
120 Extra-thin-walled 8,093 8,656 9,217 10,056 11,443 12,818 14,180 15,531 16,868 18,193 19,507
130 8,783 9,396 10,007 10,919 12,429 13,928 15,413 16,887 18,348 19,796 21,233
140 9,474 10,136 10,796 11,782 13,416 15,037 16,646 18,243 19,828 21,400 22,960
150 10,164 10,876 11,584 12,645 14,402 16,147 17,880 19,600 21,308 23,003 24,686
160 10,855 11,616 12,374 13,508 15,389 17,257 19,113 20,956 22,787 24,606 26,412
170 11,546 12,355 13,163 14,371 16,375 18,367 20,346 22,312 24,267 26,209 28,139

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
7,.5 8,0 8,5 9,0 9,5 10 11 12 14 16 18 20 22 24
Extra thick walled
42 6,381 6,708 7,023 7,324
45 6,956 7,300 7,651 7,990 8,317 8,632
48 7,491 7,892 8,280 8,656 9,020 9,371
50 7,861 8,286 8,699 9,110 9,489 9,865 10,580 11,246
51 8,046 8,484 8,909 9,322 9,723 10,111 10,851 11,542
53 8,416 8,878 9,328 9,766 10,191 10,604 11,394 12,133
54 8,601 9,075 9,538 9,988 10,426 10,851 11,665 12,429
56 8,971 9,470 9,957 10,432 10,894 11,345 12,207 13,021
57 9,156 9,667 10,167 10,654 11,128 11,591 12,479 13,317
60 9,710 10,259 10,796 11,320 11,831 12,331 13,293 14,205
63 10,265 10,851 11,424 11,985 12,534 13,070 14,106 15,093
65 10,635 11,246 11,844 12,429 13,003 13,564 14,649 15,685
68 11,190 11,838 12,473 13,095 13,706 14,304 15,463 16,573
70 11,560 12,232 12,892 13,539 14,174 14,797 16,005 17,164
73 12,115 12,824 13,521 14,205 14,877 15,537 16,819 18,052
75 12,485 13,219 13,940 14,649 15,345 16,030 17,362 18,644
76 12,670 13,416 14,150 14,871 15,580 16,276 17,633 18,940
80 13,410 14,205 14,988 15,759 16,517 17,263 18,718 20,124
83 13,965 14,797 15,617 16,425 17,220 18,003 19,532 21,012
85 14,334 15,191 16,036 16,868 17,688 18,496 20,074 21,603
89 15,074 15,981 16,875 17,756 18,626 19,483 21,160 22,787
90 15,259 16,178 17,084 17,978 18,860 19,729 21,431 23,083
95 16,184 17,164 18,132 19,088 20,031 20,962 22,787 24,563
100 17,109 18,151 19,180 20,198 21,203 22,192 24,144 26,043 29,692 33,145 36,400
102 17,479 18,545 19,600 20,642 21,671 22,689 24,686 26,634 30,383 33,934 37,288
108 18,589 19,729 20,857 21,973 23,077 24,168 26,314 28,410 32,455 36,302 39,952
110 18,959 20,124 21,277 22,417 23,546 24,662 26,856 29,002 33,145 37,091 40,839 44,391 47,745
120 20,808 22,097 23,373 24,637 25,888 27,128 29,569 31,961 36,598 41,037 45,278 49,323 53,170
130 22,658 24,070 25,469 26,856 28,231 29,504 32,282 34,921 40,050 44,983 49,718 54,255 58,596
140 24,507 26,043 27,565 29,076 30,574 32,060 34,995 37,880 43,503 48,928 54,157 59,188 64,021
150 26,357 28,016 29,662 31,295 32,917 34,526 37,707 40,839 46,955 52,874 58,596 64,120 69,447
160 28,207 29,988 31,758 33,515 35,260 36,992 40,420 43,799 50,408 56,820 63,035 69,052 74,872
170 30,056 31,961 33,854 35,733 37,603 39,458 43,133 46,758 53,861 60,766 67,174 73,984 80,298 86,414

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
0,3 0,4 0,5 0,6 0,8 1,0 1,2 1,4 1,5 1,6 1,8 2,0 2,2 2,5
Extra-thin-walled
180 8,779 9,647 10,944
190
200
210
220
240
250

Continuation of the table. 1

Outer diameter, mm Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
2,8 3,0 3,2 3,5 4,0 4,5 5,0 5,5 6,0 6,5 7,0
Extra-thin-walled Thin-walled
180 12,236 13,095 13,952 15,235 17,362 19,476 21,579 23,669 25,747 27,812 29,865
190 12,927 13,835 14,742 16,098 18,348 20,586 22,812 25,025 27,226 29,415 31,591
200 14,575 15,531 16,961 19,335 21,696 24,045 26,382 28,706 31,018 33,318
210 15,315 16,320 17,824 20,321 22,806 25,278 27,738 30,186 32,621 35,044
220 16,055 17,109 18,687 21,308 23,915 26,511 29,094 31,665 34,224 36,770
240 26,135 28,977 31,807 34,625 37,430 40,223
250 27,244 30,210 33,164 36,104 39,033 41,949

Continuation of the table. 1

Outer

diameter, mm

Theoretical weight of 1 m of pipes, kg, with wall thickness, mm
7,5 8,0 8,5 9,0 9,5 10 11 12 14 16 18 20 22 24
Thin-walled Thick-walled
180 31,906 33,934 35,950 37,954 39,945 41,925 45,846 49,718 57,313 64,712 74,913 78,917 85,723 92,333
190 33,755 35,907 38,046 40,174 42,288 44,391 48,558 52,677 60,766 68,658 76,352 83,849 91,149 98,251
200 35,605 37,880 40,143 42,393 44,631 46,857 51,271 55,636 64,218 72,603 80,791 88,781 96,574 104,170
210 37,455 39,853 42,239 44,613 46,974 49,323 53,984 58,596 67,671 76,549 85,230 93,714 102,000 110,089
220 39,304 41,826 44,335 46,832 49,317 51,789 56,697 61,555 71,124 80,495 89,669 98,646 107,425 116,008
240 43,003 45,772 48,528 51,271 54,002 56,721 62,122 67,474 78,029 88,387 98,547 108,511 118,276 127,845
250 44,853 47,744 50,624 53,491 56,345 59,188 64,835 70,433 81,481 92,333 102,986 113,443 123,702 133,764

Notes:

1. The theoretical mass of 1 m of pipe length is calculated in kilograms using the formula:

,

where M -

weight, kg;
D
n
-
outer diameter, mm;
s
wall thickness, mm.

When determining the theoretical mass of 1 m of pipes, the steel density of 7.85 g/cm3 is taken as the initial value.

2. At the consumer’s request, it is allowed to manufacture pipes with a diameter of 4 mm with a wall thickness from 0.2 to 1.2 mm, diameters of 125 and 133 mm with a wall thickness of 2.0 to 20 mm, and dimensions 29 ´ 5.5; 32 ´ 8.5; 33 ´ 1.5; 33 ´ 8.0; 39 ´ 3.0; 41 ´ 5.5; 43 ´ 8.0; 44 ´ 3.0; 46 ´ 3.0; 46 ´ 6.0; 55 ´ 9.0; 58 ´ 4.0 and 84 ´ 8.0 mm.

3. Pipes with a diameter of 100 mm or more with a D

n
/ s
more than 50 and pipes with a ratio
D
n
/ s
less than 4 are supplied according to the technical documentation agreed with the customer.

table 2

Pipe sizes Limit deviations
Outer diameter, mm:
from 4 to 10 incl. ±0.15 mm
St. 10" 30" ±0.30 mm
» 30 » 50 » ±0.40 mm
» 50 ±0,8%
Wall thickness, mm:
up to 1 ±0.12 mm
St. 1 to 5 incl. ±10%
» 1 » 2.5 with a diameter of 110 mm or more ±12%
St. 5 ±8%

4, 5. (Changed edition, Amendment No. 2).

6. Pipes must be manufactured according to the outer diameter and wall thickness. At the request of the consumer, pipes must be manufactured according to the internal diameter and wall thickness, as well as the outer and inner diameter and wall thickness.

Maximum deviations for the internal diameter of pipes should not exceed the corresponding maximum deviations for the outer diameter.

For pipes with an internal diameter of 10 mm or less, maximum deviations in the internal diameter are established by agreement between the manufacturer and the consumer.

7. Ovality and variation in wall thickness of pipes should not take their dimensions beyond the maximum deviations in outer diameter and wall thickness, respectively.

8. The curvature of any section of the pipe per 1 m length should not exceed:

3 mm - for pipes with a diameter of 4 to 8 mm;

2 mm - for pipes with a diameter of 8 to 10 mm;

1.5 mm - for pipes with a diameter over 10 mm.

At the request of the consumer, the curvature of pipes with a diameter of 20-90 mm should not exceed 1 mm per 1 m of length.

Note: For pipes with outer diameter ratio D

n to wall thickness
s manufactured
without heat treatment, curvature standards are established by agreement between the manufacturer and the consumer.

(Changed edition, Amendment No. 2).

9 . Pipe material and technical requirements for them are in accordance with GOST 8733.

Examples of symbols

Pipe with an outer diameter of 70 mm, a wall thickness of 2.0 mm, a length multiple of 1250 mm, made of steel grade 20, supplied according to the chemical composition (according to group B) GOST 8733:

The same, 6000 mm long (measurement length), made of steel grade 20, supplied according to mechanical properties and chemical composition (according to group B) GOST 8733:

The same, with combined maximum deviations (for the diameter of increased accuracy according to GOST 9567, for the wall thickness of normal accuracy):

The same, of unmeasured length, supplied without standardization of mechanical properties and chemical composition, but indicating the value of hydraulic pressure (according to group D) GOST 8733:

The same, from steel grade 10, supplied according to mechanical properties, controlled on heat-treated samples, and chemical composition (according to group G) GOST 8733:

Pipe with an internal diameter of 70 mm and a wall thickness of 2.5 mm of unmeasured length, made of steel grade 40X, supplied according to group B according to GOST 8733:

INFORMATION DATA

1. APPROVED AND ENTERED INTO EFFECT by Resolution of the State Committee of Standards of the Council of Ministers of the USSR dated October 13, 1975 No. 2604

2. INSTEAD GOST 8734-58

3. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS

Designation of the referenced technical document Item number
GOST 8733-74 9
GOST 9567-75 5, 9

4. Tested in 1991. The validity period was removed by Decree of the USSR State Standard of 11.11.91 No. 1714

5. REISSUE with Amendments No. 1, 2, 3, approved in August 1978, November 1981, March 1988 (IUS 9-78, 2-82, 6-88)

Cons of seamless pipes

Despite the large number of advantages, the pipe still has some disadvantages. Of course, they must be taken into account when choosing equipment. So, the disadvantages of steel pipes regulated by GOST No. 8734 74, 75, 78, 81, 87 include:

  • susceptibility to corrosion. Such a part has only one vulnerable area in this regard - the welded joint. However, in our time, enough ways have already been invented to eliminate such a disadvantage. This is done using various protective coatings, powder coatings, and also by adding special substances to the alloy, such as, for example, according to the GOST standard number 8733 74;
  • heavy weight. This disadvantage implies certain difficulties when transporting equipment and installing it;
  • high price. When compared with analogues made from other materials, metal equipment manufactured in compliance with all the requirements of GOST 8734 75 and 78 is quite expensive. This is explained, first of all, by manufacturing costs, because such pipes have a high cost;
  • limitation on the length of supplied segments. GOST regulates the length of manufactured pipes;
  • high thermal conductivity of products. When installed in residential premises, this may lead to the destruction of the decorative finish of the walls, as well as the danger of getting burned on the hot surface of the pipe.

Since steel pipes are heavy, the cost of using equipment for loading and transportation is inevitable

Features of cold-formed products

It is worth paying attention to several important points regarding pipe design in order to select the right product for your pipeline.

Steel pipes produced in accordance with the GOST document differ:

  • high level of thermal conductivity. This is fraught with some unpleasant moments. For example, if you are using the product to supply hot water in your home, it is best not to install the pipes tightly against the walls, as the outer surface of the product may fog up. And this will lead to dampness on the walls and, as a result, the appearance of fungus or mold;
  • good electrical conductivity. Therefore, the cold-deformed part is not used to protect and insulate electrical cables;
  • susceptible to liquid freezing. Try to install communications from pipes GOST 8734 74, 75, 78 in conditions more or less close to normal temperatures. If the transported liquid freezes inside the pipe, there is a risk of damage to the surface of the product;
  • restriction of segments. For 1 km of communications, with a pipe diameter (according to the 8734 78 standard) of 110 mm, there will be approximately 83-85 joints, and, accordingly, weak points.

Material for production

Steel pipes owe many of their advantages and disadvantages, of course, to the material from which they are made. Steel is a type of metal alloy that is resistant to the development of corrosion processes, strength and long service life.

The quality and properties of pipes depend on the raw materials used for the blanks

Having a dense structure, the pipe, manufactured in accordance with state standard No. 8733 74, is airtight and not subject to mechanical damage. Difficulties may arise when it is necessary to transport chemically aggressive substances using such pipes. The action of some of them can have a detrimental effect on the performance and strength characteristics of the material.

The pipes in accordance with GOST No. 8733 74 include high quality carbon and alloy steel. This provides a certain level of resistance to the effects of biologically and chemically active substances, however, this feature is not absolute for any aggressive environment. It is better to consult a specialist before using pipes for supplying caustic liquids and gaseous media.

Production process

In order to better understand the types of equipment and its quality, it is not a bad idea to familiarize yourself with the process of its manufacture, since it is at this stage that all the necessary parameters and qualities of the product, as provided for by GOST, are formed.

In the manufacture of pipes, in accordance with 8734 81 standards, the seamless production method is used. First, an ingot is made from a carbon steel alloy (according to the conditions of standard No. 8733 74). Then, inside it, with the help of special equipment (a rolling mill with rotating rolls operating on a drive), plastic deformation of the workpiece occurs. As a result of this procedure, a hole of the required diameter is formed inside the ingot. At the same stage, the thickness of the workpiece walls is also adjusted.

Finished pipes are checked for compliance with the parameters defined by accepted standards

The specificity of the pipe manufactured according to this GOST is that the cold rolling method is used in its production. This means that during the formation of the product, according to standard No. 8734 75, the metal temperature is maintained at a lower temperature than that required for recrystallization. After the main part of the process is completed, the pipe is tested to ensure that it meets all stated quality standards. The part is checked for strength, resistance to damage and other parameters. Next, the products are packaged and prepared for sale.

Round thin-walled steel pipe

A steel pipe with a wall thickness not exceeding 1.5 mm is classified as non-standard rolled metal. Products of this type are difficult to manufacture, however, due to their small diameter, the use of such products makes it possible to solve highly specialized specific problems. And in some cases, there may simply be no alternative to a thin-walled pipe.

Thin-walled steel pipes are used only in areas where there are no heavy loads on the pipeline

Application of thin-walled pipes

A few words about the specifics of products of this type. Since we are talking about technical products, its definition should contain numbers, and not a subjective assessment of belonging to one class or another. So: the range of thin-walled steel pipes includes products with a wall thickness of no more than 1.5 millimeters or if the value of the coefficient determined by the formula

K= Din/Sst., where

Din. is the outer diameter, and S st. – wall thickness, lies in the range of 12.5...40.

A good example of the use of thin-walled metal products includes pneumatic and hydraulic drive systems in the automotive, aviation and shipbuilding industries.

Of course, the above-mentioned area of ​​application for thin-walled steel pipes is far from the only one. They can be found in such industries as:

  • construction;
  • housing and communal services sector;
  • furniture manufacturing;
  • boiler houses of energy enterprises.

Architectural elements or decorative items can be made from steel pipes

In everyday life, these products are also not uncommon. But here they are most often used when engineering communications must have moderate strength, sufficient to withstand only low loads. In this case, we are talking primarily about a thin-walled steel pipe for electrical wiring.

Steel pipe production

Depending on the production method, there are three types of thin-walled steel pipe products:

  • cold-formed seamless;
  • hot-formed seamless;
  • electric welded

Each type has its own characteristics, which affect the strength and possibility of using them in a particular industry.

Cold-deformed seamless pipes (GOST 8734-75). The production process for products of this type is practically the same as in the case described above. The main two differences are:

  1. The stitched sleeve is cooled and passes through all the rollers at a relatively low temperature.
  2. At the final stage, heat treatment is carried out. Thus, by eliminating the stress in the metal, which always occurs during cold deformation, the steel acquires elasticity and toughness. After this, the rollers are recalibrated.

Cold deformation is one of the methods for producing seamless steel pipes

Electric welded pipes. They are produced in accordance with GOST 10704 from flat steel sheet, which is unwound from a roll, and then cut into strips of small width. At the next stage, the sheets are welded into an endless strip. The workpiece thus obtained is fed to an automatic welding machine. The welding procedure is performed mainly in two ways:

  • high-frequency induction currents using the so-called HF technology;
  • welding in an inert environment with an electric arc is already a TIG technology.

Note! When purchasing thin-walled metal pipes, you will most likely be offered products manufactured by the HF method. The TIG seam is considered more durable. However, in those areas where a very reliable thin-walled small diameter is required, preference should be given to seamless rolled pipe.

After cooling, the workpiece undergoes flaw detection. At this stage, quality control is carried out, as well as the tightness of the seam. The dimensions required by GOST are ensured by calibration on rollers.

Hot-deformed seamless pipes. The production of products of this type is regulated by the requirements of GOST 8732-78.

  • the workpiece is a monolithic steel cylinder. First, the rod (this is another name for the cylindrical billet) is sent to the furnace, where it is heated to the metal recrystallization temperature;
  • then a hollow cylinder inside is formed from plastic steel on a piercing press - a sleeve, characterized by irregular dimensions and shape;
  • After passing through a series of rollers, the workpiece acquires the diameter and required wall thickness determined by the assortment. After calibration, the cooled pipe is cut into pieces of the required length and packaged.

Finished pipes undergo inspection, including visual inspection, as well as measurements with special devices and tools.

It should be noted that when passing through the rollers, a mandrel is present inside the pipe.

Technical characteristics of thin-walled steel pipe

The weight of this product is the main factor on the basis of which its price is calculated. In addition to the assortment, GOSTs contain tables of the mass of one linear meter of thin-walled steel pipe depending on the wall thickness and diameter. You can get an idea of ​​the relationship between these characteristics of such parts by studying the table below. It contains selective data concerning only some standard sizes of cold-formed products.

Scope of application

Pipes manufactured in accordance with GOST 8734 75, 87 (hot and cold deformed) are a very popular product. And not only in the plumbing products market, but also in various branches of the engineering and furniture industries. In addition, the use of seamless cold-deformed steel pipes according to GOST 8734 74 is also acceptable for decorating premises. However, the most popular, of course, are pipes as an element of communication systems. These can be water pipes adapted to supply cold and hot water. In addition, such a pipe is used to supply and transport fuel substances, as well as gaseous and liquid chemically active substances.

Helpful advice! It is worth keeping in mind that steel is susceptible to the effects of some particularly aggressive chemicals, therefore, when choosing a material for a communication system, pay attention to the properties of the working environment and check the actual parameters of the pipe material with the standards of GOST 8734 75 and 8733 74.

Steel gives off heat well, so pipes made from it are often used for the production of heating devices

Steel pipes are manufactured in various lengths, diameters and thicknesses. Therefore, this material is very convenient for the manufacture of various furniture elements (table and chair legs, backrests, etc.) and decor.

Thin-walled steel pipe: production, range and application

Articles

In this article we will try to find out what a thin-walled steel pipe is, how it is produced, what sizes it comes in and where it is used.

Definition

Which pipe is considered thin-walled?

This is what thin-walled pipes look like before being sent to the customer

Since we are not talking about subjective perception, but about technical terminology, we need an accurate definition, preferably in numbers. So: a thin-walled pipe is one whose ratio of outer diameter to wall thickness is in the range from 12.5 to 40, or which has walls thinner than 1.5 mm .

Please note: there are also particularly thin-walled pipes, the walls of which, of course, are also often thinner than 1.5 mm.

In general, their ratio of outer diameter to wall thickness is more than forty, however, for pipes with a minimum diameter, the smallest wall thickness is limited by production capabilities.

Hence thin-walled pipes with a diameter of 5 mm and walls 1.5 mm thick (ratio 3.(3) or especially thin-walled 5x0.5 (ratio 10).

Here the ratio of diameter and wall thickness can be assessed visually

Production

From a production point of view, all thin-walled steel pipes sold in the country fall into one of three categories:

  • Electric welded pipes;
  • Hot-formed seamless;
  • Cold-formed seamless.

A lot of articles have already been written about pipe production methods, so let’s just go over the main points.

Electric welded

Strips - raw materials for welded pipes

  • The strips are welded into an endless strip;
  • Which is fed to an automatic welding machine. Welding is carried out in several ways; the most common are TIG (electric arc welding in an inert gas environment) and HF (welding with high-frequency induction currents);

Please note: If you are purchasing small diameter electric welded steel thin wall pipes, you will most likely be offered HF welded pipes.

TIG seam is considered more durable; however, in applications where strong, thin-walled, small-diameter pipes are needed, seamless pipes are preferred.

For the production of decorative chrome-plated tubes, the method by which welding is performed is indifferent, so the market is saturated with pipes that are cheaper to produce.

  • The welded workpiece is cooled;
  • Passes flaw detection to determine the quality and tightness of the seam;
  • Calibrated in rollers;
  • Cut into pieces of the required length;
  • It undergoes visual inspection, is packaged and sent to the finished product warehouse.

Before us is the final calibration of the pipe

Seamless hot-formed pipes

  • The workpiece is a so-called rod - a monolithic steel cylinder . First, it is sent to the furnace, where it is heated to the steel recrystallization temperature;
  • Then, on a piercing press, a sleeve is formed from ductile metal - a cylinder hollow inside. It still differs from the pipe in its irregular shape and size;
  • Then the workpiece passes through several rollers in succession, where it acquires the required diameter and wall thickness. All this time, the mandrel remains inside the pipe;
  • The calibrated and cooled pipe is cut into pieces and packaged.

During most of the production stages, the pipe is hot

Seamless cold-formed pipes

The production process in general terms looks the same as in the previous case.

Classification and parameters of pipes

Depending on certain factors, there are different types and types of pipes. According to the cross-sectional shape they are distinguished:

  • cold-deformed seamless steel pipes GOST 8734 75 and hot-deformed GOST 8734 87 annular section;
  • profile (flat-oval, rectangular, oval).

Seamless pipes include cold-deformed and hot-deformed pipes, the production of which is regulated by GOSTs 8734 81 and 87 (the latter for hot-deformed ones). A distinctive feature is the absence of a seam. This gives them some advantage in strength, a percentage of 5-10%. There are also welded steel products produced according to standard 8734 74. They are straight-seam (the seam is located along the entire length of the pipe) and spiral-seam (when the pipe is stitched in a spiral).

By purpose:

  • special. These include, for example, profile ones. Such pipes are used to replace reinforcement structures and load-bearing elements during construction and repairs;
  • general purpose. This is a standard seamless pipe with an annular cross-section, used for water supply, gas transmission and heating systems. Its quality is regulated by standard No. 8734 75 - for cold-formed and 87 - for hot-formed.

According to the ratio of diameter and wall thickness:

  • especially thin-walled. The diameter of such pipes, in accordance with the standards of standard 8734 78, is 20 mm, and the wall thickness is 0.5 mm. The ratio of these parameters for such pipes is more than 40;
  • thin-walled with the same diameter, but with thicker walls - their thickness ranges from 0.5 to 20 mm;
  • thick-walled, according to the 78th standard, characterized by a diameter from 6 to 250 mm, wall thickness 1.6 – 24 mm;
  • especially thick-walled.

The range of seamless steel pipes includes products with a wide range of diameters and wall thicknesses

Directory of rolled metal products

Seamless cold-deformed pipes in %CITY%

This type of metal products includes cold-deformed (cold pipes) and heat-deformed general-purpose pipes made of carbon and alloy steel, manufactured by outer diameter, wall thickness and length.

The range of pipes corresponds to GOST 8734-78.

Depending on the ratio of the outer diameter (Dn) to the wall thickness (s), they are divided into:

— thin-walled pipes with Dn/s from 12.5 to 40 and pipes with a diameter of 20 mm or less with a wall of 1.5 mm;

— thick-walled pipes with Dn/s from 6 to 12.5;

— especially thin-walled pipes Dn/s more than 40 and pipes with a diameter of 20 mm and a wall of 0.5 mm or less;

- especially thick-walled pipes with Dn/s less than 6.

Thick-walled pipes are manufactured by heat treatment. Thin-walled pipes are produced without heat treatment, in which the ratio of the outer diameter to the wall thickness is 50 or more.

Thin-walled pipe works well for bending. Such cold-pressed pipes of small diameter are widely used for the manufacture of furniture and electric lighting fittings.

According to the length of the cold pipe, they are divided into: - unmeasured length from 1.5 to 11.5 m; — measured length from 4.5 to 9 m with maximum deviations along the length + 10 mm; — multiple measured lengths from 1.5 to 9 m with an allowance for each cut of 5 m

Depending on the quality indicators, thick-walled and thin-walled pipes are manufactured in the following groups B, B, D, E: B - with normalization of the chemical composition from mild steel grades according to GOST 1050, GOST 14959, GOST 4543 and GOST 19281; B - with standardization of mechanical properties, controlled on heat-treated samples and chemical composition, of steel grades according to GOST 1050, GOST 14959, GOST 4543 and GOST 19281. Standards of mechanical properties must comply with the requirements of the relevant standards for steel; D - without standardization of mechanical properties and chemical composition, but with standardization of test hydraulic pressure; E - after special heat treatment. Steel grades, heat treatment conditions and standards of mechanical properties are established by documentation approved in the prescribed manner.

Depending on the purpose and technical requirements, thin-walled pipes and thick-walled pipes are made from steel grades with a chemical composition in accordance with GOST 380-94, GOST 1050, GOST 4543, GOST 19281.

Seamless pipes are options without a welded spiral or longitudinal seam. For production, rolling is used on machines known as pipe rolling units. Seamless pipe has found its worthy recognition in the field of aircraft manufacturing, automobile and tractor manufacturing, boiler manufacturing and other areas of mechanical engineering. It is also an excellent help in the chemical and oil industries, various types of public utilities.

Pipe rolling production includes the production of seamless cold-rolled pipes (cold rolling of pipes after hot rolling is required), seamless hot-rolled pipes (rolling is carried out in a hot condition).

The long-term development of pipe rolling production allows today to effectively use various pipe rolling units, the difference between which lies in the standard size of the output pipes; classification by type of rolling is also possible.

Seamless cold-rolled pipes (cold-deformed pipes), produced in accordance with GOST 8734-78. Outer diameter 8-450 mm, wall thickness can range from 0.08 to 20 mm. The unmeasured length is in the range of 1.5-11.5 m, the measured length is 4.5-9 m.

A variety of production methods allows you to ensure a high level of strength in relation to atmospheric pressure, saving your own time and money for choosing materials.

Differences between seamless pipes may lie in the grade of steel used in production, the thickness and diameter of the walls. The main steel grades for the production of seamless pipes are: steel 9G2s, steel 20, steel 10, st 35, st 40x, st45, st30KhGSA. This variety allows you to always find the best option that will exactly match your priorities.

Seamless pipes are those that do not have a welded spiral or longitudinal seam.

They are made by rolling a heated ingot on special machines, which make a hole in the center of the pipe. Unlike other pipes, seamless pipes have increased strength and reliability, which allows them to be used in areas such as aircraft manufacturing, mechanical engineering, as well as in the oil and chemical industries, etc.

The size of the pipes is determined by the outer diameter. Rolling of hot-deformed seamless pipes is carried out in accordance with GOST 8732–78 and GOST 8731-74, for steel varieties: steel 10, steel 20, steel 35, steel 45, steel 09g2s, etc.

The range of pipes corresponds to GOST 8734-78.

Depending on the ratio of the outer diameter (Dn) to the wall thickness (s), they are divided into:

— thin-walled pipes with Dn/s from 12.5 to 40 and pipes with a diameter of 20 mm or less with a wall of 1.5 mm;

— thick-walled pipes with Dn/s from 6 to 12.5;

— especially thin-walled pipes Dn/s more than 40 and pipes with a diameter of 20 mm and a wall of 0.5 mm or less;

- especially thick-walled pipes with Dn/s less than 6.

Thick-walled pipes are manufactured by heat treatment. Thin-walled pipes are produced without heat treatment, in which the ratio of the outer diameter to the wall thickness is 50 or more.

Thin-walled pipe works well for bending. Such cold-pressed pipes of small diameter are widely used for the manufacture of furniture and electric lighting fittings.

According to the length of the cold pipe, they are divided into:

  1. unmeasured length from 1.5 to 11.5 m;
  2. measured length from 4.5 to 9 m with maximum length deviations + 10 mm;
  3. multiple measured lengths from 1.5 to 9 m with an allowance for each cut of 5 mm.

Depending on the quality indicators, thick-walled and thin-walled pipes are manufactured in the following groups B, C, D, E:

B - with standardization of the chemical composition of mild steel grades according to GOST 1050, GOST 14959, GOST 4543 and GOST 19281;

B - with standardization of mechanical properties, controlled on heat-treated samples and chemical composition, of steel grades according to GOST 1050, GOST 14959, GOST 4543 and GOST 19281. Standards of mechanical properties must comply with the requirements of the relevant standards for steel;

D - without standardization of mechanical properties and chemical composition, but with standardization of test hydraulic pressure;

E - after special heat treatment. Steel grades, heat treatment conditions and standards of mechanical properties are established by documentation approved in the prescribed manner.

Depending on the purpose and technical requirements, thin-walled pipes and thick-walled pipes are made from steel grades with a chemical composition in accordance with GOST 380-94, GOST 1050, GOST 4543, GOST 19281.

Weight of cold-formed seamless steel pipes

Outer diameter, mm Wall thickness, mm Weight 1m, kg Meters per ton Outer diameter, mm Wall thickness, mm Weight 1m, kg Meters per ton
d 6 1,6 0,174 5759,8 d 56 4,5 5,715 175
1,8 0,186 5363,6 5 6,289 159
d 7 1,6 0,213 4693,2 5,5 6,85 146
1,8 0,231 4332,2 6 7,398 135,2
d 8 1,6 0,253 3959,9 6,5 7,935 126
1,8 0,275 3633,4 7 8,459 118,2
d 9 1,6 0,292 3424,7 7,5 8,971 111,5
1,8 0,32 3128,8 8 9,47 105,6
d 10 1,6 0,331 3017 8,5 9,957 100,4
1,8 0,364 2747,2 9 10,432 95,9
d 11 1,6 0,371 2696,1 d 57 5 6,412 156
1,8 0,408 2448,6 5,5 6,985 143,2
d 12 1,6 0,41 2436,8 6 7,546 132,5
1,8 0,453 2208,6 6,5 8,095 123,5
2 0,493 2027,5 7 8,632 115,9
d 13 1,6 0,45 2223,1 7,5 9,156 109,2
1,8 0,497 2011,4 8 9,667 103,4
2 0,543 1843,1 8,5 10,167 98,4
d 14 1,6 0,489 2043,8 9 10,654 93,9
1,8 0,542 1846,5 9,5 11,129 89,9
2 0,592 1689,5 d 60 5 6,782 147,5
2,2 0,64 1562 5,5 7,392 135,3
d 15 1,6 0,529 1891,3 6 7,99 125,2
1,8 0,586 1706,6 6,5 8,576 116,6
2 0,641 1559,6 7 9,149 109,3
2,2 0,694 1440 7,5 9,71 103
2,5 0,771 1297,6 8 10,259 97,5
d 16 1,6 0,568 1759,9 8,5 10,796 92,6
1,8 0,63 1586,4 9 11,32 88,3
2 0,691 1448,2 9,5 11,831 84,5
2,2 0,749 1335,6 d 63 5,5 7,799 128,2
2,5 0,832 1201,5 6 8,434 118,6
d 17 1,6 0,608 1645,7 6,5 9,057 110,4
1,8 0,675 1482,1 7 9,667 103,4
2 0,74 1351,6 7,5 10,265 97,4
2,2 0,803 1245,4 8 10,851 92,2
2,5 0,894 1118,6 8,5 11,424 87,5
2,8 0,981 1019,8 9 11,985 83,4
d 18 1,6 0,647 1545,3 9,5 12,534 79,8
1,8 0,719 1390,6 d 65 5,5 8,07 123,9
2 0,789 1267,2 6 8,73 114,5
2,2 0,857 1166,5 6,5 9,378 106,6
2,5 0,956 1046,4 7 10,013 99,9
2,8 1,05 952,7 7,5 10,635 94
3 1,11 901,1 8 11,246 88,9
d 19 1,6 0,687 1456,5 8,5 11,844 84,4
1,8 0,764 1309,7 9 12,429 80,5
2 0,838 1192,6 9,5 13,003 76,9
2,2 0,911 1097,1 10 13,564 73,7
2,5 1,017 983 d 68 5,5 8,477 118
2,8 1,119 893,9 6 9,174 109
3 1,184 844,8 6,5 9,858 101,4
d 20 1,8 0,808 1237,8 7 10,53 95
2 0,888 1126,4 7,5 11,19 89,4
2,2 0,966 1035,5 8 11,838 84,5
2,5 1,079 926,8 8,5 12,473 80,2
2,8 1,188 842 9 13,095 76,4
3 1,258 795,1 9,5 13,706 73
3,2 1,326 754,3 10 14,304 69,9
d 21 1,8 0,852 1173,3 11 15,463 64,7
2 0,937 1067,1 d 70 6 9,47 105,6
2,2 1,02 980,4 6,5 10,179 98,2
2,5 1,141 876,7 7 10,876 91,9
2,8 1,257 795,7 7,5 11,56 86,5
3 1,332 750,9 8 12,232 81,8
3,2 1,405 711,9 8,5 12,892 77,6
3,5 1,511 662 9 13,539 73,9
d 22 1,8 0,897 1115,2 9,5 14,174 70,6
2 0,986 1013,7 10 14,797 67,6
2,2 1,074 930,9 11 16,005 62,5
2,5 1,202 831,8 d 73 6 9,914 100,9
2,8 1,326 754,3 6,5 10,66 93,8
3 1,406 711,4 7 11,394 87,8
3,2 1,484 674 7,5 12,115 82,5
3,5 1,597 626,2 8 12,824 78
d 23 2 1,036 965,5 8,5 13,521 74
2,2 1,129 886,1 9 14,205 70,4
2,5 1,264 791,2 9,5 14,877 67,2
2,8 1,395 716,9 10 15,537 64,4
3 1,48 675,8 11 16,819 59,5
3,2 1,563 640 12 18,052 55,4
3,5 1,683 594,1 d 75 6,5 10,981 91,1
d 24 2 1,085 921,6 7 11,739 85,2
2,2 1,183 845,5 7,5 12,485 80,1
2,5 1,326 754,4 8 13,219 75,7
2,8 1,464 683,1 8,5 13,94 71,7
3 1,554 643,6 9 14,649 68,3
3,2 1,641 609,2 9,5 15,346 65,2
3,5 1,769 565,1 10 16,03 62,4
4 1,973 506,9 11 17,362 57,6
d 25 2,2 1,237 808,4 12 18,644 53,6
2,5 1,387 720,9 d 76 6,5 11,141 89,8
2,8 1,533 652,3 7 11,912 84
3 1,628 614,4 7,5 12,67 78,9
3,2 1,72 581,3 8 13,416 74,5
3,5 1,856 538,9 8,5 14,15 70,7
4 2,072 482,7 9 14,871 67,2
d 26 2,2 1,291 774,4 9,5 15,58 64,2
2,5 1,449 690,2 10 16,277 61,4
2,8 1,602 624,2 11 17,633 56,7
3 1,702 587,7 12 18,94 52,8
3,2 1,799 555,8 d 80 7 12,602 79,4
3,5 1,942 514,9 7,5 13,41 74,6
4 2,17 460,8 8 14,205 70,4
d 27 2,2 1,346 743,2 8,5 14,988 66,7
2,5 1,511 662 9 15,759 63,5
2,8 1,671 598,4 9,5 16,517 60,5
3 1,776 563,2 10 17,263 57,9
3,2 1,878 532,4 11 18,718 53,4
3,5 2,028 493 12 20,124 49,7
4 2,269 440,8 d 83 7 13,12 76,2
4,5 2,497 400,5 7,5 13,965 71,6
d 28 2,5 1,572 636,1 8 14,797 67,6
2,8 1,74 574,7 8,5 15,617 64
3 1,85 540,7 9 16,425 60,9
3,2 1,957 511 9,5 17,22 58,1
3,5 2,115 472,9 10 18,003 55,5
4 2,368 422,4 11 19,532 51,2
4,5 2,608 383,4 12 21,012 47,6
d 30 2,5 1,695 589,8 d 85 7 13,465 74,3
2,8 1,878 532,4 7,5 14,334 69,8
3 1,998 500,6 8 15,191 65,8
3,2 2,115 472,8 8,5 16,036 62,4
3,5 2,287 437,2 9 16,868 59,3
4 2,565 389,9 9,5 17,688 56,5
4,5 2,83 353,4 10 18,496 54,1
5 3,083 324,4 11 20,074 49,8
d 32 2,8 2,016 496 12 21,603 46,3
3 2,146 466,1 d 89 7,5 15,074 66,3
3,2 2,273 440 8 15,981 62,6
3,5 2,46 406,5 8,5 16,875 59,3
4 2,762 362 9 17,756 56,3
4,5 3,052 327,7 9,5 18,626 53,7
5 3,329 300,4 10 19,483 51,3
d 34 2,8 2,154 464,2 11 21,16 47,3
3 2,294 436 12 22,787 43,9
3,2 2,431 411,4 d 90 7,5 15,259 65,5
3,5 2,633 379,9 8 16,178 61,8
4 2,959 337,9 8,5 17,084 58,5
4,5 3,274 305,5 9 17,978 55,6
5 3,576 279,6 9,5 18,86 53
5,5 3,866 258,7 10 19,729 50,7
d 35 3 2,368 422,4 11 21,431 46,7
3,2 2,51 398,5 12 23,083 43,3
3,5 2,719 367,8 d 95 8,5 18,132 55,1
4 3,058 327 9 19,088 52,4
4,5 3,385 295,4 9,5 20,031 49,9
5 3,699 270,3 10 20,962 47,7
5,5 4,001 249,9 11 22,787 43,9
d 36 3 2,441 409,6 12 24,563 40,7
3,2 2,588 386,3 d 100 8,5 19,18 52,1
3,5 2,805 356,5 9 20,198 49,5
4 3,157 316,8 9,5 21,203 47,2
4,5 3,496 286,1 10 22,195 45,1
5 3,823 261,6 11 24,144 41,4
5,5 4,137 241,7 12 26,043 38,4
6 4,439 225,3 14 29,692 33,7
d 38 3,2 2,746 364,1 16 33,145 30,2
3,5 2,978 335,8 18 36,4 27,5
4 3,354 298,2 d 102 8,5 19,6 51
4,5 3,718 269 9 20,642 48,4
5 4,069 245,8 9,5 21,671 46,1
5,5 4,408 226,8 10 22,689 44,1
6 4,735 211,2 11 24,686 40,5
d 40 3,2 2,904 344,3 12 26,634 37,5
3,5 3,151 317,4 14 30,383 32,9
4 3,551 281,6 16 33,934 29,5
4,5 3,94 253,8 18 37,288 26,8
5 4,316 231,7 d 108 9 21,973 45,5
5,5 4,68 213,7 9,5 23,077 43,3
6 5,031 198,8 10 24,168 41,4
6,5 5,37 186,2 11 26,314 38
d 42 3,5 3,323 300,9 12 28,41 35,2
4 3,749 266,8 14 32,455 30,8
4,5 4,162 240,3 16 36,302 27,5
5 4,562 219,2 18 39,952 25
5,5 4,951 202 d 110 9 22,417 44,6
6 5,327 187,7 9,5 23,546 42,5
6,5 5,691 175,7 10 24,662 40,5
7 6,042 165,5 11 26,856 37,2
d 45 4 4,044 247,3 12 29,002 34,5
4,5 4,495 222,5 14 33,145 30,2
5 4,932 202,7 16 37,091 27
5,5 5,358 186,6 18 40,839 24,5
6 5,771 173,3 d 120 10 27,128 36,9
6,5 6,172 162 11 29,569 33,8
7 6,56 152,4 12 31,961 31,3
7,5 6,936 144,2 14 36,598 27,3
d 48 4 4,34 230,4 16 41,037 24,4
4,5 4,827 207,1 18 45,279 22,1
5 5,302 188,6 d 130 10 29,594 33,8
5,5 5,765 173,5 11 32,282 31
6 6,215 160,9 12 34,921 28,6
6,5 6,652 150,3 14 40,05 25
7 7,078 141,3 16 44,983 22,2
7,5 7,491 133,5 18 49,718 20,1
8 7,892 126,7 20 54,255 18,4
d 50 4,5 5,049 198 d 140 12 37,88 26,4
5 5,549 180,2 14 43,503 23
5,5 6,036 165,7 16 48,928 20,4
6 6,511 153,6 18 54,157 18,5
6,5 6,973 143,4 20 59,188 16,9
7 7,423 134,7 d 150 14 46,956 21,3
7,5 7,861 127,2 16 52,874 18,9
8 8,286 120,7 18 58,596 17,1
d 51 4,5 5,16 193,8 20 64,12 15,6
5 5,672 176,3 22 69,447 14,4
5,5 6,172 162 d 160 14 50,408 19,8
6 6,659 150,2 16 56,82 17,6
6,5 7,133 140,2 18 63,035 15,9
7 7,596 131,7 20 69,052 14,5
7,5 8,046 124,3 22 74,872 13,4
8 8,484 117,9 d 170 14 53,861 18,6
8,5 8,909 112,2 16 60,766 16,5
d 53 4,5 5,382 185,8 18 67,474 14,8
5 5,919 169 20 73,985 13,5
5,5 6,443 155,2 22 80,298 12,5
6 6,955 143,8 24 86,414 11,6
6,5 7,454 134,2 d 180 18 71,913 13,9
7 7,941 125,9 20 78,917 12,7
7,5 8,416 118,8 22 85,723 11,7
8 8,878 112,6 24 92,333 10,8
8,5 9,328 107,2 d 190 18 76,352 13,1
d 54 4,5 5,493 182 20 83,849 11,9
5 6,042 165,5 22 91,149 11
5,5 6,578 152 24 98,251 10,2
6 7,103 140,8 d 200 20 88,781 11,3
6,5 7,614 131,3 22 96,574 10,4
7 8,114 123,2 24 104,17 9,6
7,5 8,601 116,3 d 210 20 93,714 10,7
8 9,075 110,2 22 102 9,8
8,5 9,538 104,8 24 110,089 9,1
9 9,988 100,1 d 220 20 98,646 10,1
22 107,426 9,3
24 116,008 8,6
d 240 20 108,511 9,2
22 118,277 8,5
24 127,845 7,8
d 250 22 123,702 8,1
24 133,764 7,5

Specifications

To choose the right equipment needed for specific purposes, you need to study its technical parameters. All parameters correspond to their own standard number:

  1. GOST No. 8734 78 determines the outer diameter, length and wall thickness of products;
  2. GOST 8734 75 is responsible for the quality of products entering the market;
  3. GOST 8734 74 - regulates the production part, that is, it determines the standards for metal rolling;
  4. GOST 9941 81 applies to hot and cold rolled stainless steel pipes, regulating product manufacturing standards;
  5. GOST 8734 87 determines the quality of hot-deformed rolled metal.

Such an important quality as the chemical composition, on which the scope of application of the product directly depends, is regulated by standard No. 8733 74.

Equipment and equipment

If you are confident in your abilities and decide to make the pipeline yourself, then be prepared to acquire special equipment.

Helpful advice! If the volume of work is small, then it will be much more profitable to rent equipment, since if purchased, the costs will not be recouped. However, if there is a lot of work, then on the contrary - it is more profitable to buy a device than to pay for its rental.

So, you will need a pipe bender. This is a device adapted for bending and deforming. Such equipment will become a necessity, especially if the room in which the system is installed has hard-to-reach corners or curved walls.

In addition, you will need devices for cutting pipes, as well as chamferers, threading machines and devices (clamps), and devices for rolling grooves. Select such equipment in accordance with the parameters of wall thickness, diameter and length of pipes specified in standard No. 8734 75, 78, 87.

Connecting steel pipes, especially large diameters, requires the use of welding and welding skills

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