Canted Coil Spring

Solution

Key Technical Characteristics

Axial and Radial Compliance: Exhibits simultaneous axial deflection up to 60% of free length and radial deflection of 30-50% of coil diameter without permanent deformation

Load Distribution: Maintains uniform contact pressure of 0.7-35 MPa across mating surfaces even under misalignment conditions

Dynamic Performance: Capable of 107 to 109 cycles at moderate loads (20-70% of maximum deflection) depending on material

Temperature Range: Standard stainless steel variants operate from -200°C to +300°C, with specialized alloys extending to 800°C

Electrical Resistance: Contact resistance as low as 1-10 mΩ when used in electrical applications

Primary Applications

canted coil springs serve critical functions across multiple industries due to their unique combination of mechanical properties:

Aerospace and Defense

In aircraft and spacecraft electrical systems, canted coil springs provide redundant grounding paths with contact resistance below 5 mΩ, maintaining conductivity even under vibration levels exceeding 20 G. They serve in avionics connectors, missile guidance systems, and satellite deployment mechanisms where reliability must be maintained across temperature swings of -65°C to +150°C.

Medical Devices

Implantable medical components utilize biocompatible canted coil springs (typically made from MP35N or Elgiloy alloys) with fatigue lives exceeding 500 million cycles. Applications include lead retention in pacemakers (maintaining 2-5 N retention force) and MRI-compatible connectors where magnetic permeability must remain below 1.05 μr.

Oil and Gas

Downhole tools employ canted coil springs that maintain sealing integrity at pressures up to 20,000 psi while compensating for thermal expansion differentials of 0.5-3 mm in high-temperature environments (175-250°C). They prevent gas leakage in wellhead equipment with helium leak rates below 1×10-6 atm·cc/sec.

Automotive Electronics

Electric vehicle battery systems use canted coil springs for cell-to-cell connections, providing constant contact force of 10-50 N while accommodating ±1.5 mm movement from thermal cycling. Their current-carrying capacity reaches 50-200 A depending on wire cross-section and plating.

Maintenance and Care Procedures

Proper maintenance ensures optimal performance and longevity of canted coil springs:

Cleaning Protocols

For most applications, ultrasonic cleaning in 50-60°C solutions with 3-5% alkaline detergent (pH 9-11) for 5-10 minutes at 40 kHz effectively removes contaminants. Critical medical applications may require passivation in 20-25% nitric acid at 49-60°C for 20-30 minutes to restore corrosion resistance.

Inspection Criteria

Periodically examine springs for:

Coil spacing uniformity (tolerance ±0.05 mm)

Surface defects exceeding 10% of wire diameter

Permanent set greater than 2% of free length after compression

Corrosion pits deeper than 0.01 mm in critical applications

Lubrication Requirements

For dynamic applications, apply thin films (2-5 μm) of perfluoropolyether (PFPE) grease for high-temperature environments or silicone-based lubricants (ISO VG 10-22) for standard conditions. Avoid petroleum-based lubricants in oxygen-rich environments due to flammability risks.

Storage Conditions

Store springs in controlled environments with:

Temperature: 15-25°C

Relative humidity: 40-60% RH

Protective atmosphere: Nitrogen purge for precious metal alloys

Orientation: Flat storage to prevent creep deformation