DINSEN Spring Clamp – Precision Sealing Solution Compliant with DIN3021

Key Specifications

Standard: DIN 3021 (Part 1: Dimensions & Materials; Part 2: Technical Delivery Conditions) 

Material: Spring steel (e.g., 51CrV4, C75S)

Band Width: 12mm/15mm 

Temperature Range: -40°C to +200°C 

Surface Treatment: Chromium(VI)-free zinc flake coating; corrosion resistance up to 720h salt spray

Forms: Type A / Type B

Constant Clamping Force

The DINSEN spring clamp employs a precision-engineered spring band design that maintains near-constant radial force across the entire service life. This ensures: Leak-free sealing under thermal cycling and pressure fluctuations; No relaxation or loss of tension over time

• Elimination of manual re-torquing after installation

Robust Material Performance

• High-tensile alloy spring steel with exceptional resistance to brittle fracture, even at low temperatures 

• Optional surface protection: galvanized, black oxide, or passivated—meeting automotive ELV directives 

Application Versatility

The DIN3021 hose clamp is suitable for:

• Automotive systems: fuel lines, coolant circuits, charge air ducts, power steering, air intake, heating/cooling 

• Industrial machinery: engine manufacturing, agricultural equipment, white goods 

• Fluid handling: water/brine outlet lines, air ducts, fuel vent systems

Quality Assurance – Comprehensive Inspection Protocol

Every DINSEN spring clamp batch undergoes a rigorous multi-stage inspection process aligned with DIN3021 technical delivery conditions :

1. 100% Visual Inspection

• Burr height ≤0.02mm; no sharp edges, cracks, rust, or plating defects 

2. Dimensional Accuracy

• Core inner diameter tolerance: ±0.05mm

• Full geometric verification: circularity, parallelism, fillet radius 

3. Surface Treatment Validation

• Coating thickness: galvanized ≥8μm; passivation ≥3μm

• Cross-cut adhesion test; salt spray resistance 

4. Mechanical Performance Testing

• Hardness: 65Mn HV420-480 / 304SS HV380-450

• Clamping force per DIN3021-2 test requirements 

• 50-cycle resilience test: rebound deviation ≤2%

• Long-term endurance and tightness verification 

5. Simulated Assembly & Functional Tests

• Pressure-holding tightness (hydraulic/pneumatic)

• Torque resistance for double-ear clamps

• Fatigue life: 1000+ cycles (standard); 5000+ cycles (automotive grade)

Why Choose DINSEN Spring Clamps?

✔ DIN3021 Compliant – Fully meets German and international hose clamp standards 
✔ Self-Adjusting Design – Maintains sealing integrity under temperature extremes (-40°C to +200°C) 
✔ No Maintenance Required – Permanent clamping force eliminates re-tightening 
✔ Environmentally Responsible – Chromium(VI)-free coatings comply with end-of-life vehicle directives 
✔ Proven in Automotive & Industrial Applications – Trusted by leading manufacturers worldwide 

📩 Contact DINSEN today to discuss your application requirements or request a sample batch of our DIN3021 spring clamps.