DIN 1629 Structural Seamless Tube

DIN 1629: Seamless Circular Unalloyed Steel Tubes Subject to Special Requirements

Standard: DIN 1629
EOI can provide different grades of structural steel pipes, such as St37.0, St44.0, St52.0, and the like.


  • DIN 1629 structural steel tube is applicable for manufacturing pipelines, containers, equipment, pipe fittings and steel complexes.
  • These structural steel pipes are predominantly use within construction of chemical plants, vessels, pipeworks and for general mechanical engineering aims.
  • Size Range The size range of DIN 1629 structural steel tube is as follows:
  • Outer dimension is produced by 6.0 mm to 219.0 mm.
  • Wall thickness of this structural steel pipe ranges from particular.0 mm to 30 millimeter.
  • The maximum length is 12000 millimeters.
  • Advantages of DIN 1629 Structural Steel Tube
  • JST advanced rolling technology makes the quality of pipes obtain the standard quantity. Under the advanced rolling technology, our structural steel pipes challenging purer but smaller tolerance range than that produced by other manufacturers
  • JST configures micro oxidation and non-oxidation heat treatment furnace that present the required thermal treatment temperature for structural steel tubes. The temperature difference is controlled within 5℃. After heat treatment, an individual no oxidation layer close to the pipe. The structural steel pipe acquires higher surface quality and stable motion. Thus the usage own life is improved.
  • We possess multiple inspection machines for testing the inside and outside surface quality of plumbing.
  • JST configures UNICORN ultrasonic joint inspection machine, automatic ultrasonic inspection machine and magnetic flux leakage inspection machine to look at the obvious defects on leading of structural steel tubes or structural steel conduits. We also own professional surface inspectors who gain the relevant appropriate qualifications. Our company provides regular training and carries out artificial inspection for the interior and outside defects of pipes to make certain stable performance of water pipes.
  • The actual JST advanced rolling technology, the allowable deviation of DIN 1629 structural steel tube is controlled within the standard range, even smaller than the standard range.
  • Packaging of DIN 1629 Structural Steel PipeCustomers can opt bare, bundles, crates or crate protection at the both sides of tubes. Daily also package products as per customers' requirements

Parameters of DIN 1629 Structural Steel Tube

1. Chemical Composition of DIN 1629 Structural Steel Pipe

Standard Grade Chemical Composition Limits (%)
C Si Mn P S Cr Mo
DIN1629 St37.0 ≤ 0.17 / / ≤ 0.040 ≤ 0.040 / /
St44.0 ≤ 0.21 / / ≤ 0.040 ≤ 0.040 / /
St52.0 ≤ 0.22 ≤ 0.55 ≤ 1.70 ≤ 0.040 ≤ 0.040 / /

2. Mechanical Properties of DIN 1629 Structural Steel Tube

Standard Grade Tensile Strength (MPa) Yield Strength (MPa) Elongation (%)
DIN1629 St37.0 350-480 ≥ 235 ≥ 25
St44.0 420-550 ≥ 255 ≥ 21
St52.0 500-650 ≥ 270 ≥ 21

Other Parameters

1. Max. Working Pressure and Temperature of St37.0, St44.0 and St52.0

  Max. Working Pressure Max. Working Temperature (°C) Provided Document
D ≤ 219.1 64 300 DIN 50049
219.1< D ≤ 660 25 300
D > 660 16 300

Note: a. 1bar=0.1MPa

b. DIN50049 is Germany metal product inspection file type standard.

2. Outer Diameter Deviation of Structural Steel Pipe

Outer Diameter (mm) Outside Diameter Deviation
Pipe Body and Pipe End Pipe End: It needs to be specially dealed.
≤ 100 ±1%D或±0.5mm ± 0.4 mm
100 < D ≤ 200 ±1%D ± 0.5 % D
> 200 ±1%D ± 0.6% D

Note: a. Pipe end refers to the place within 100 mm to the pipe port.

b. The allowable deviation may involve the inside diameter and cause the allowable deviation of wall thickness. Thus we should take the inside diameter into consideration when formulating the agreement content.

3. DIN1629 Wall Thickness Allowable Deviation

D ≤ 130 mm 130 < D ≤ 320 mm 320 < D ≤ 660 mm
≤ 2Sn 2Sn < S ≤ 4Sn > 4Sn ≤ 0.05D 0.05D < S ≤ 0.11D >0.11D ≤ 0.05D 0.05D < S ≤ 0.09D > 0.09D
+15% -10% +12.5%
± 9% +17.5%
± 12.5% ±10% +20%

Note: Sn is the length deviation of DIN1629 with standard thickness regulated in DIN2448.

4. Inspection Item of Structural Steel Tube

No. Inspection Item Inspection Range Inspection Responsibility Pipe Billet Inspection Documents
1 Tensile Test Choose one sample from a batch of steel pipes. Determined in Consultation DIN50049-3.1A
2 Flattening Test The wall thickness of one end of regulated steel pipe sample should not exceed 40 mm. It does flattening test. Determined in Consultation
3 Compactness Test Test each steel pipe. Manufacturer
4 Surface Test Test each steel pipe. Determined in Consultation
5 Diameter Test Test each steel pipe. Determined in Consultation
6 Product Analysis Determined in Consultation Manufacturer

5. Allowable Shape Deviation of Structural Steel Pipe

Roundness The outside roundness should be controlled within the allowable deviation.
Straightness It must be straight in visual inspection. If there is any special requirement, we make according to users' requirements.

6. Tube End Polishing

1. Tube end should be vertical to the pipe central axis after cutting. There is no burr on the pipe end.
2. According to agreement, we use steel pipes with the wall thickness of 3.2 mm to do polishing.
3. The angle of side channel is 30°. The surface thickness of steel pipe end is1.6 mm (±0.8 mm).

7. Allowable Weight Deviation of Structural Steel Tube

Weight Deviation of Each Steel Pipe +12%, -8%
Weight Deviation of a Batch of Steel Pipes with the Weight of More than 10 Tons =10%, -5%

Note: DIN2448 regulated the weight of steel pipes per unit of length.

Need A Quote?

We'll do our best to support your business growth.