Труба бесшовная CT 20 ГОСТ 8732-78

We are a professional manufacturer of Seamless pipe St20 GOST 8732-78 in China.Мы профессиональный производитель бесшовных труб St20 по ГОСТ 8732-78 в Китае.
GOST 8732-78 is a Russian standard for seamless pipes.

The standard applies to hot-rolled seamless steel pipes of general purpose, manufactured on the outer diameter, wall thickness and length.These pipes are designed for high-pressure, high-temperature, and critical applications in industries such as oil & gas, petrochemical, power generation, and mechanical engineering.

Specifications of GOST 8732-78 Ct20 Pipes

  • Standard: GOST 8732-78

  • Steel Grade: CT20 (Ст20 / Steel 20, a low-carbon steel)

  • Manufacturing method: Hot-finished seamless

  • Outer diameter: 20 mm – 550 mm

  • Wall thickness: 2 mm – 75 mm

Chemical Composition of GOST 8732-78 Ct20 steel pipes

Element Percentage Range
Carbon (C) 0.07-0.14
Manganese (Mn) 0.35-0.65
Silicon (Si) 0.17-0.37
Phosphorus (P) ≤0.035
Sulfur (S) ≤0.035

Please note that the above figures are approximate ranges and may vary slightly depending on the specific grade.

Mechanical Properties of GOST 8732-78 Ct20 steel pipes

Property Value
Ultimate Tensile Strength (MPa) ≥490
Yield Strength (MPa) ≥245
Elongation (%) ≥24
Hardness less than 156HB

 

GOST 8732-78 Dimension Chart
Outside diameter, mm Mass of 1 m of pipes, kg, at wall thickness, mm
2.5 2.6* 2.8 3 3.2* 3.5 4 4.5 5 5.5 6 -6.5 7 -7.5 8
20* 1.08 1.12 1.19 1.26 1.33 1.42 1.58
21.3* 1.16 1.2 1.22 1.35 1.43 1.54 1.71
22* 1.2 1.24 1.33 1.41 1.48 1.6 1.78
25 1.39 1.44 1.53 1.63 1.72 1.86 2.07 2.28 2.47 2.65 2.81 2.97 3.11 3.24 3.35
26.9* 1.5 1.56 1.66 1.77 1.87 2.02 2.25 2.49 2.7 2.9 3.09 3.27 3.43 3.59 3.83
28 1.57 1.63 1.74 1.85 1.96 2.11 2.37 2.62 2.84 3.05 3.26 3.45 3.63 3.79 3.95
30* 1.7 1.76 1.88 2 2.12 2.29 2.57 2.83 3.08 3.32 3.55 3.77 3.97 4.16 4.34
31.8* 1.81 1.86 2 2.13 2.26 2.44 2.74 3.03 3.3 3.57 3.82 4.05 4.28 4.49 4.69
32 1.82 1.88 2.02 2.15 2.27 2.46 2.76 3.05 3.33 3.59 3.85 4.09 4.32 4.53 4.74
33.7* 1.92 1.99 2.13 2.27 2.41 2.61 2.93 3.24 3.54 3.82 4.1 4.36 4.61 4.84 5.07
35* 2 2.08 2.22 2.37 2.51 2.72 3.06 3.39 3.7 4 4.29 4.57 4.83 5.09 5.33
38 2.19 2.27 2.43 2.59 2.75 2.98 3.35 3.72 4.07 4.41 4.74 5.05 5.35 5.64 5.92
40* 2.31 2.4 2.57 2.74 2.9 3.15 3.55 3.94 4.32 4.68 5.03 5.37 5.7 6.01 6.31
42 2.44 2.53 2.71 2.89 3.06 3.32 3.75 4.16 4.56 4.95 5.33 5.69 6.01 6.38 6.71
42.4* 2.46 2.55 2.73 2.91 3.09 3.36 3.79 4.2 4.61 5 5.38 5.75 6.11 6.45 6.79
44.5* 2.59 2.69 2.88 3.07 3.26 3.54 4 4.44 4.87 5.29 5.7 6.09 6.47 6.84 7.2
45 2.62 2.72 2.91 3.11 3.3 3.58 4.04 4.49 4.93 5.36 5.77 6.17 6.56 6.94 7.3
48.3* 2.82 2.93 3.14 3.35 3.58 3.87 4.37 4.86 5.34 5.8 6.26 6.7 7.13 7.54 7.95
50 2.93 3.04 3.26 3.48 3.69 4.01 4.54 5.05 5.55 6.04 6.51 6.97 7.42 7.86 8.29
51* 3.55 3.77 4.1 4.64 5.16 5.67 6.17 6.65 7.13 7.6 8.04 8.48
54 3.77 4.01 4.36 4.93 5.49 6.04 6.58 7.1 7.61 8.11 8.6 9.08
57 4 4.25 4.62 5.23 5.83 6.41 6.99 7.55 8.1 8.63 9.16 9.67
60* 4.22 4.48 4.88 5.52 6.16 6.78 7.39 7.99 8.58 9.15 9.71 10.26
60.3* 4.24 4.5 4.9 5.55 6.19 6.82 7.43 8.03 8.62 9.2 9.76 10.32
63.5 4.48 4.76 5.18 5.87 6.55 7.21 7.87 8.51 9.14 9.75 10.36 10.95
68 4.81 5.11 5.57 6.31 7.05 7.77 8.48 9.17 9.86 10.53 11.19 11.84
70 4.96 5.27 5.74 6.51 7.27 8.02 8.75 9.47 10.18 10.88 11.56 12.23
73 5.18 5.51 6 6.81 7.6 8.39 9.16 9.91 10.66 11.39 12.12 12.82
76 5.4 5.74 6.26 7.1 7.94 8.76 9.56 10.36 11.14 11.91 12.67 13.42
82.5* 6.82 7.74 8.66 9.56 10.44 11.32 12.18 13.03 13.87 14.7
83 6.86 7.79 8.71 9.62 10.51 11.39 12.26 13.12 13.96 14.8
89 7.38 8.39 9.38 10.36 11.33 12.28 13.23 14.16 15.07 15.98
95 7.9 8.98 10.04 11.1 12.14 13.17 14.19 15.19 16.18 17.16
102 8.5 9.67 10.82 11.96 13.09 14.21 15.31 16.4 17.48 18.55
104* 9.86 11.04 12.21 13.36 14.5 15.63 16.74 17.85 18.94
108 10.26 11.49 12.7 13.9 15.09 16.27 17.44 18.59 19.73
114 10.85 12.15 13.44 14.72 15.98 17.23 18.47 19.7 20.91
121 11.54 12.93 14.3 15.67 17.02 18.35 19.68 20.99 22.29
127 12.13 13.6 15.04 16.48 17.9 19.32 20.72 22.1 23.48
133 12.73 14.26 15.78 17.29 18.79 20.28 21.75 23.21 24.66
140 15.04 16.55 18.24 19.83 21.4 22.96 24.51 26.04
146 15.7 17.39 19.06 20.72 22.36 24 25.62 27.23
152 16.37 18.13 19.87 21.6 23.32 25.03 26.73 28.41
159 17.15 18.99 20.82 22.64 24.45 26.24 28.02 29.79
165* 19.73 21.63 23.53 25.41 27.28 29.13 30.97
168 20.1 22.04 23.97 25.89 27.79 29.69 31.57
178* 21.33 23.4 25.45 27.49 29.52 31.53 33.54
180 21.58 23.67 25.75 27.81 29.87 31.91 33.93
194 23.31 25.57 27.82 30.06 32.28 34.5 36.7
203 29.15 31.5 33.84 36.16 38.47
219 31.52 34.06 36.6 39.12 41.63
245 38.23 41.09 43.93 46.76
273 42.72 45.92 49.11 52.28
299 53.92 57.41 62.34
324* 58.54 62.34
325 58.73 62.54
351 67.67
356* 68.66
377

 

Dimensional tolerances – Outside diameter

Outside diameter, mm Permissible deviation of outside diameter – Enhanced accuracy Permissible deviation of outside diameter – Usual accuracy
Less than 50 ± 5 mm ± 5 mm
50 – 219 ± 0.8 % ± 1.0 %
More than 219 ± 1.0 % ± 1.25 %

Dimensional tolerances – Wall thickness

Outside diameter, mm Wall thickness, mm Permissible deviation for wall thickness – Enhanced accuracy Permissible deviation for wall thickness – Usual accuracy
Less than 219 S ≤ 15 ± 12.5 % +12.5/-15 %
Less than 219 15 < S ≤ 30 +10/-12.5 % ± 12.5%
Less than 219 S > 30 ± 10 +10/-12.5 %
More than 219 S ≤ 15 +12.5/-15.0 %
More than 219 15 < S ≤ 30 ± 12.5 %
+10.0/-12.5%
More than 219 S > 30

Трубы стальные бесшовные горячедеформированные ГОСТ 8732-78 чаще всего используются в трубопроводных системах, где необходимо главное качество трубного проката – прочность. Труба стальная г/к, благодаря своим высоким эксплуатационно-техническим параметрам, пользуется спросом в строительстве, при изготовлении монолитно-каркасных конструкций, как наиболее оптимальный и рентабельный материал.

Основные направления применения:

  • газовая и нефтяная промышленность;
  • автомобилестроение;
  • авиационное строительство;
  • тяжелое машиностроение;
  • химическая промышленность.