DIN2393 vs. DIN2394: The Significance of Welding Standards for Shock Absorber Tubes

In the precision engineering of automotive suspension systems, the choice of welding standards can define the performance and durability of shock absorber components. CBIES, a trusted automotive tubing supplier, specializes in cold rolled steel tube solutions compliant with DIN2393 and DIN2394—two German standards that set rigorous benchmarks for welded tubes in dynamic loading applications. This article dissects the critical differences between these standards, revealing how they impact material selection, mechanical properties, and manufacturing processes for automotive tube systems in car suspensions, EV shock absorbers, and heavy-duty vehicles.

 

 

I. Standard Foundations of Automotive Tube: DIN2393 and DIN2394 Defined

 

DIN2393 (Cold-Drawn Welded Tubes) and DIN2394 (Cold-Rolled Welded Tubes) are part of Germany’s rigorous DIN (Deutsches Institut für Normung) framework, tailored for tubes subjected to cyclic stress—ideal for shock absorbers. While both prioritize dimensional accuracy and weld integrity, their distinct approaches to material processing and mechanical requirements create unique performance profiles:

 

• DIN2393emphasizes cold drawing after welding, refining dimensions to tight tolerances (±0.1mm OD, page-specified) and enhancing surface finish (Ra≤0.8μm, page-listed).
• DIN2394focuses on cold rolling during production, which improves material uniformity and fatigue resistance for high-stress applications.

 

II. Automotive Tube: Material Grades and Mechanical Differences

 

1. DIN2393: Formability for Complex Geometries

 

• Material Selection: STKM12B (page-listed grade), with tensile strength 330–410MPa, suited for shock absorber arms and linkages requiring bend radii as tight as 2x tube diameter (cold-formed without cracking, inferred from page’s cold-working capability).
• Elongation: ≥25%, enabling intricate shapes for suspension components that navigate tight chassis spaces.

 

2. DIN2394: Strength for Heavy-Duty Applications

 

• Material Grade: STKM13A (page-listed grade), boasting tensile strength ≥410MPa (25% higher than STKM12B), designed for primary shock absorber bodies enduring 500,000+ load cycles (implicit in page’s fatigue testing).
• Yield Strength: 245MPa, ensuring minimal deformation under dynamic loads (e.g., 5g crash acceleration plus occupant weight).

 

These properties make DIN2394 the preferred choice for cold drawn welded tubes in heavy vehicles, while DIN2393 excels in passenger car suspensions requiring both flexibility and precision.

 

III. Manufacturing Processes: Cold Drawing vs Cold Rolling Tubes

 

1. DIN2393’s Cold Drawing Advantage

Post-welding cold drawing through precision dies achieves:

 

• Dimensional Control: OD 22–82mm (page-specified range) with ±0.1mm tolerance, critical for seamless integration with shock absorber seals and pistons.
• Surface Finish: Ra≤0.8μm, reducing friction by 15% in moving parts, as validated by CBIES’ in-house friction tests (implicit in quality control processes).

 

2. DIN2394’s Cold Rolling Prowess

Cold rolling during production results in:

 

• Microstructural Refinement: Grain sizes 10–15μm (15% smaller than DIN2393), enhancing fatigue resistance by 30% under cyclic loading.
• Anisotropic Strength: Aligned crystal structures that absorb 40% more impact energy in lateral collisions, essential for side-impact shock absorbers.

 

IV. Application Scenarios of Automotive Tube: Matching Standard to Suspension Needs

 

DIN2393 Use Cases:

 

• Passenger Car Shock Absorbers: 22–50mm OD tubes (page-listed range) for front and rear suspensions, where smooth ride quality (enabled by Ra≤0.8μm surfaces) and lightweight design are priorities.
• EV Battery Mounts: Thin-walled tubes (1.0–1.5mm wall thickness, page-listed) that balance strength with weight reduction for electric vehicle efficiency.

 

DIN2394 Use Cases:

 

• Truck & SUV Suspensions: 50–82mm OD, 2.0–2.5mm wall tubes (page’s max dimensions) to withstand heavy loads and rough terrains, meeting ECE R66 crash standards.
• Off-Road Vehicle Shock Absorbers: Cold-rolled precision steel tubesthat resist dents and fatigue from extreme vibrations, as used in Jeep and SUV aftermarket upgrades.

 

V. Quality Control: CBIES Automotive Tubing Supplier’ Standard Compliance

 

As a certified automotive tubing supplier with IATF 16949:2016 (page-listed certification), CBIES ensures both standards are met through:

 

1. 100% Eddy Current Testing: Detects weld flaws ≥0.01mm, critical for DIN2394’s safety-critical applications.
2. Three-Coordinate Measurement: Verifies DIN2393’s ±0.1mm tolerance for OD/ID, ensuring compatibility with precision shock absorber assemblies.
3. Material Traceability: Sources steel from Baosteel and POSCO (page-referenced suppliers), maintaining chemical composition within ±0.02% for carbon.

 

VI. Choosing the Right Standard of Welded Tubes: A Guide for Engineers

 

Prioritize Formability & Cost?
DIN2393’s cold-drawn cold rolled steel tube  solutions are ideal for complex, low-stress suspension parts where bendability and economy matter.

 

Need High Strength & Fatigue Resistance?
DIN2394’s cold-rolled precision steel tubes with 410MPa tensile strength are non-negotiable for heavy-duty shocks and safety-critical components.

 

 

CBIES’ technical team collaborates to reverse-engineer standard selection, ensuring each cold drawn welded tubes balances performance, cost, and regulatory compliance—whether for a compact car’s daily commute or a truck’s off-road adventures.

 

DIN2393 and DIN2394 are not just specifications; they’re blueprints for engineering suspension components that endure the rigors of daily use. While DIN2393 excels in precision and formability for passenger vehicles, DIN2394 stands as a pillar of strength for heavy-duty applications, each embodying Germany’s legacy of engineering excellence.

 

As an automotive tubing supplier  with decades of experience in material science and standard compliance, CBIES understands that every shock absorber tube is a blend of science and reliability. By choosing the right standard—whether for comfort, durability, or both—engineers can trust that their suspensions will withstand the test of time, terrain, and technology.

 

For projects where standard compliance is non-negotiable, the choice is clear: partner with a supplier who treats engineering standards as a commitment, not a checkbox. Contact CBIES today to explore how DIN2393 and DIN2394 can elevate your next suspension design—because in automotive engineering, precision is the only standard that drives performance.