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Leak Prevention in Double-Wall Diesel Tanks
A ground double-wall diesel fuel storage tank prevents leakage at connection points through precision engineering, specialized seals, and rigorous quality control.
1. Welded and Flanged Joints with Redundant Seals
Critical connections use continuous, gas-shielded arc welding to create seamless, leak-proof bonds. Welds are inspected via non-destructive testing (NDT).
Connection Specifications
- Full-penetration welding for primary wall connections
- NDT inspection (radiography/ultrasonic testing)
- Raised-face flanges with spiral-wound gaskets
- Stainless steel/graphite gasket materials
- Standardized bolt torquing protocols
2. Penetration Seals for Dual-Wall Systems
Where pipes or sensors pass through both walls, dual-seal assemblies are employed to maintain containment integrity.
Sealing Components
- Welded/threaded primary wall fittings
- Secondary wall flange/compression fittings
- Annular seals (O-rings, PTFE gaskets)
- Test ports between primary/secondary seals
- Welded baffles to prevent fuel bypass
3. Flexible Hoses and Expansion Joints
Movement Accommodation
- Stainless steel-braided flexible hoses
- EPDM/Viton hose linings
- Bellows expansion joints in fixed piping
- Corrugated metal/rubber components
- Pressure/temperature rated connections
4. Non-Metallic and Composite Sealing Solutions
Advanced Materials
- Polyurethane/nylon seals for non-metallic parts
- Chemical-resistant adhesives for bonding
- Composite adapters for hybrid materials
- Epoxy transition layers
- Galvanic corrosion prevention
5. Pressure Testing and Quality Assurance
Comprehensive testing protocols ensure all connections maintain leak-proof integrity throughout the tank's service life.
Testing Procedures
- Hydrostatic/pneumatic pressure testing (1.5x operating)
- Annular space vacuum/positive pressure tests
- Visual inspections for wear/rust
- Bolt torque verification
- Infrared imaging for hidden leaks