Spirally welded steel tubes for petroleum pipe lines

Execution standards

SR EN 10208-1 Steel tubes for pipe lines for combustible fluids. Tubes in regulation class A.
Dimensions and linear weights According to SR EN 10208-1
Steel L 235 GA,L 245 GA, L 290 GA, L 360 GA

DIN 1626 Steel pipes for pipelines for transport of combustible fluids and gases.
Dimensions and linear weights According to DIN 2458
Steel St 37.2, St 44.2, St 52.2

API 5L 44-th Ed./2007 PSL 1 and PSL 2
 Steel pipes for gas, water and oil in the petroleum and natural gases industry.
Dimensions and linear weights See table 1.1
Steel Grd B, X42, X46, X52

QUALITY TECHNICAL CONDITIONS ACCORDING TO SR EN 10208/1

Outside diameter, mm Wall thickness, mm
5,0 5,6 6,3 7,1 8 8,8 10,0 11,0 12,5
Linear weight (kg/ml)
219,1 26,40 29,48 33,06 37,12 41,64 - - - -
273 33,04 36,92 41,43 46,45 52,18 - - - -
323,9 39,23 43,95 49,34 55,47 62,32 68,38 - - -
355,6 43,23 48,33 54,26 61,02 68,57 75,26 - - -
406,4 49,49 55,35 62,16 69,91 78,60 86,28 97,75 107,26 121,42
457 - 62,34 70,02 78,77 88,58 97,26 110,23 120,98 137,02
508 - 69,38 77,94 87,70 98,64 108,33 122,81 134,82 152,74
559 - - 85,87 96,63 108,70 119,40 135,39 148,65 168,46
610 - - 93,79 105,56 118,76 130,47 147,96 162,49 184,19
660 - - 101,56 114,32 128,63 141,32 160,02 176,05 199,60
711 - - 109,48 123,25 138,69 152,39 172,87 189,89 215,32
762 - - 117,41 132,18 148,75 163,46 185,45 203,72 231,04
813 - - - 141,11 158,82 174,52 198,03 217,56 246,76
864 - - - 150,04 168,88 185,59 210,60 231,39 262,49
914 - - - 158,79 178,74 196,44 222,53 244,94 277,90
1016 - - - - 198,87 218,58 248,09 272,63 309,34
1067 - - - - 208,93 229,65 260,67 286,46 325,06
1118 - - - - - 240,71 273,24 300,30 340,79
1167 - - - - - 251,35 285,33 313,59 355,89
1219 - - - - - 262,63 298,15 327,70 371,92
1321 - - - - - 284,77 323,31 355,37 403,36
1422 - - - - - 306,69 348,22 382,77 434,50
1524 - - - - - 328,83 373,37 410,44 465,94
1626 - - - - - 350,96 398,52 438,11 497,39

2. Tolerances
2.1. Outside diameter
  • diameter ≤ 610 mm; ± 0,5 mm or ± 0.75% D (whichever is higher), but max. ± 3 mm
  • 610 < diameter ≤ 1430 mm: ± 0,5% D but max. ± 4 mm
  • diameter > 1430 mm: by agreement
2.2. Wall thickness
  • wall thickness ≤ 10 mm: +1,0 mm/-0,5 mm
  • 10 < wall thickness < 20 mm: +10%/-5%
3. Lengths
  • normal lengths
Length range Length range for 90% of ordered items (m) Minimum average length of ordered item (m) Shortest length of ordered item (m)
r1 6 ÷ 11 8 4
r2 9÷ 14 11 6
r3 10÷ 16 13 7
r4 11 ÷ 18 15 8
  • fixed lengths: delivery tolerance ± 500 mm
4. Chemical composition (%)
4.1 Chemical composition on analysis on liquid steel

Steel symbol C max. Si max. Mn max. P max. S max.
Alphanumeric Numeric
L 235 GA
L 245 GA
L 290 GA
L 360 GA		 1.0458
1.0459
1.0483
1.0499		 0,16
0,20
0,20
0,22		 0,40
0,40
0,40
0,45		 1,20
1,15
1,40
1,45		 0,030
0,030
0,030
0,030		 0,030
0,030
0,030
0,030

4.2 Chemical composition on product analysis - tolerances as to limits of chemical composition on analysis on liquid steel

Element Tolerances
C + 0,02
Si + 0,05
Mn + 0,10
P + 0,005
S + 0,005

5. Mechanical requirements

Steel grade Yield limit
Rp 0,2, min. (N/mm²)		 Tensile strength
Rm, min. (N/mm²)		 Elongation A
min. (%)
L 235 GA 235 370 ÷ 510 23
L 245 GA 245 415 ÷ 555 22
L 290 GA 290 415 ÷ 555 21
L 360 GA 360 460 ÷ 620 20

6. Hydrostatic pressure test
Hydrostatic test pressure is calculated by the formula:
p =20 × S × T
D
where:
  • p = hydrostatic test pressure, in bar
  • D = specified outside diameter, mm
  • S = stress, in N/mm², equal to a percentage of minimum yield limit specified for the respective steel grade
  • T = minimum specified wall thickness, in mm
Test pressure must not exceed 207 bar.
Test pressure must be maintained for at least:
  • 5 sec for pipes with outside diameter ≤ 457 mm
  • 10 sec for pipes with outside diameter > 457 mm
7. Other quality checks
  • non-destructive TVX checks along the length of welded seam up to 102 mm from the ends. The end zone and the repaired ones are XR and / or US checked.
  • ultrasonic non-destructive checking of tubes in the technological line
  • tensile testing of base material
  • impact bend testing of base material at 20 °C *
  • tensile testing of seam
  • bend testing of seam
  • checking of chemical analysis on pipe *
* At customer's request

III. Protection, marking, documents, delivery
  • the pipes are delivered unprotected
  • the pipes are delivered with bevelled ends to an angle of 30°C ± 5°C keeping a front ring of 1,50 ± 0,79 mm
  • each pipe will be marked - stencilled and painted at about 305 mm from one of the ends
  • each lot of pipes will be accompanied by the mill test certificate according to EN 10204/DIN 50049
  • the delivery will be made by railway, truck or ship