Haihao Group, a trusted manufacturer of steel piping systems in China, recently completed the production of a batch of DIN 2448 ST 35.8 seamless steel pipes for a long-term customer in Singapore. Though this standard has been officially replaced by EN norms, it continues to be widely requested due to its clear dimensional system and historical significance in industrial pipelines.
In this article, we’ll explore the key technical specifications, dimensional series, and enduring value of DIN 2448 standard seamless pipes — and explain why ST 35.8 grade is still relevant in many international projects.
DIN 2448 ST 35.8 seamless steel pipes
What Is DIN 2448?
DIN 2448 is a historic German standard that defines the dimensions, weight, and tolerances of seamless carbon steel pipes. While it doesn’t specify material grades, it is typically used with carbon steel materials such as ST 35.8, ST 37.0, or ST 52.0.
The standard has since been replaced by EN 10220 for dimensional aspects, and EN 10216 / EN 10210 / EN 10297 for material and delivery conditions. However, DIN 2448 remains widely referenced in legacy systems, procurement specs, and industrial usage, especially in Asia, the Middle East, and Africa.
Key Dimensional Features
DIN 2448 defines pipe dimensions using the DN (Nominal Diameter) system with fixed outside diameters (OD). The wall thickness varies by series, providing flexibility for different pressure ratings.
Nominal Sizes and Outside Diameters
Each DN corresponds to a fixed OD, unlike the American NPS system where slight OD differences exist. For example:
DN 25 = OD 33.7 mm
DN 50 = OD 60.3 mm
DN 100 = OD 114.3 mm
Wall Thickness Series (Reihe)
DIN 2448 defines several wall thickness levels:
Reihe 1 (Series 1) – Light series
Reihe 2 (Series 2) – Medium series (most common)
Reihe 3 (Series 3) – Heavy series
Reihe 4 (Series 4) – Extra heavy-duty
These correspond to pressure requirements and affect internal diameter and pipe weight.
DIN 2448 seamless steel pipes
Theoretical Pipe Weight
Each pipe’s weight is calculated based on its OD and wall thickness, with values provided in the standard (kg/m). This simplifies structural and logistic planning.
Material: ST 35.8 and Equivalents
While DIN 2448 does not assign a material grade, it is often used with ST 35.8, a non-alloy carbon steel with good mechanical strength and weldability. Equivalent modern materials include:
S235JR / S275JR / S355JR (EN 10210-1)
ASTM A53 Grade B (similar chemical range)
Delivery conditions (tensile strength, chemical composition, etc.) typically follow DIN 1629, EN 10216-1, or client-specific requirements.
Tolerances and Inspection
DIN 2448 provides strict tolerances for:
Outside diameter
Wall thickness
Straightness and ovality
Inspection methods such as hydrostatic testing, UT/ET, chemical analysis, and dimensional checks are typically applied based on project specifications.
Applications of DIN 2448 Seamless Pipes
Despite its age, DIN 2448 ST 35.8 pipes remain widely used in:
- Industrial pipelines for water, oil, air, and gas
- Boiler and pressure vessel systems
- Mechanical hydraulic/pneumatic piping
- Heating and HVAC pipelines
- Structural supports in construction and machinery
Their versatility and straightforward dimensions make them especially popular in refurbishment or legacy equipment projects.
DIN 2448 vs American Standards (NPS/Schedule)
| Feature | DIN 2448 | ASTM/ASME (NPS) |
| Diameter Basis | DN (Nominal Diameter) | NPS (Nominal Pipe Size) |
| OD | Fixed per DN | Fixed per NPS (slightly different) |
| Wall Thickness | Series (Reihe 1/2/3/4) | Schedule (SCH 10/40/80…) |
| Common Series | Reihe 2 | SCH 40 |
| Pipe Weight Calculated | Based on OD + wall thickness | Same |
Conversion is not direct — refer to detailed charts when comparing specs.
DIN 2448: Replaced, But Not Forgotten
Although DIN 2448 has been replaced by EN 10220 (latest version: EN 10220:2017), the dimensional formats from DIN 2448 — especially Reihe 2 — continue to be globally used and recognized. Manufacturers like Haihao Group still produce pipes according to DIN 2448 Series 2 dimensions upon request.
For welded pipes, DIN 2458 was the counterpart to DIN 2448 (also replaced by EN), but the dimensional conventions remain similar.
Why Choose Haihao Group for DIN 2448 Pipes?
Over 40 years of steel pipe manufacturing experience
Own production lines for seamless and welded steel pipes
Full QA/QC including EN 10204 3.1/3.2 certification
Strong export portfolio in Asia, Europe, Middle East
Custom production of legacy specs like DIN 2448 ST 35.8 to fit your system
Contact Us Today
Looking for DIN 2448 ST 35.8 seamless steel pipes or custom pipe solutions?
Haihao Group offers OEM manufacturing, third-party inspection, and global delivery — all with precision and reliability.
