Compression spring LM40 series

tractiontorsioncoiled

Overview
A multi turn shim end wave spring (also known as a coiled wave spring or microwave spring) is manufactured from pre-hardened flat wire using on-edge coiling (edge-winding) with waves added to provide spring action. These springs are designed for applications requiring tight load-deflection specifications where axial space is critical.

Capabilities

• Spring thickness: 0.15 mm to 0.7 mm
• Spring outside diameter: 12 mm to 60 mm
• Designed for tight load-deflection control and space-constrained axial applications

Classification

• By load type: compression, tension, torsion
• By structure: cylindrical coil springs, variable diameter coil springs (variable diameter mainly for compressive loads)
• By shape: conical, scroll, concave, convex
• By production method & material diameter: large coil springs (typically hot-formed) and small coil springs (typically cold-formed)

Features

• Precise adjustment performance (sensitive force-displacement relationship)
• Good softness with relatively wide deformation range
• Relatively easy to manufacture
• Compact structure
• High energy rate

Material properties (INCONEL 718)
Corrosion resistance: 718 grade stands up well in various atmospheric environments including seawater exposure. Heat resistance: precipitation-hardenable nickel-chromium alloy with high creep-rupture strength, suitable for elevated temperatures up to about 700°C. Offers good solderability and allows age hardening, facilitating welding and annealing without spontaneous hardening during aggressive heating and cooling.

Applications

• Aerospace: actuators and dampers in aircraft systems
• Medical devices: springs in orthodontic and other medical devices
• Automotive: suspension components and powertrain systems
• Industrial equipment: gearboxes, pumps, valves for compression/tension control
• Electronics: components in switchgear, connectors, peripherals
• Oil & gas: springs for downhole tools and related equipment

Additional features & advantages

• Stackability: shim end design permits stacking multiple springs for compact, high-force solutions
• Improved load distribution: wave-shaped coils give more uniform load distribution vs. traditional compression springs
• Space savings: reduced operating height for constrained-height applications
• Constant load characteristics across compression range
• Improved fatigue life due to reduced stress concentrations
• Customization: available in various sizes, materials, and coatings to meet application requirements
• Ease of installation: shim ends simplify positioning and alignment
• Cost-effective: durable design reduces replacement and maintenance frequency

Specification:
Part No. | Operates in (Bore Diameter) | Lears Shaft Diameter | Load (N) | Work Height (mm) | Free Height (mm) | Waves | Turns | Thickness (mm) | Radial Wall | Spring Rate (N/MM)
LM40-H1 | 40 | 30 | 300 N | 5.66 | 9.14 | 4.5 | 3 turns | 0.46 | 3.38 | 86.21
LM40-L1 | 40 | 30 | 100 N | 2.9 | 9.14 | 3.5 | 3 turns | 0.41 | 3.38 | 16.03
LM40-M1 | 40 | 30 | 150 N | 5.44 | 9.14 | 3.5 | 3 turns | 0.53 | 3.63 | 40.54
LM40-H2 | 40 | 30 | 300 N | 7.54 | 12.19 | 4.5 | 4 turns | 0.46 | 3.38 | 64.52
LM40-L2 | 40 | 30 | 100 N | 3.86 | 12.19 | 3.5 | 4 turns | 0.41 | 3.38 | 12
LM40-M2 | 40 | 30 | 150 N | 7.24 | 12.19 | 3.5 | 4 turns | 0.53 | 3.63 | 30.3
LM40-H3 | 40 | 30 | 300 N | 9.42 | 15.24 | 4.5 | (data not fully specified) | (data not fully specified) | (data not fully specified) | (data not fully specified)

Caractéristiques / spécifications techniques

• Commercial designation: Multi Turn Shim End Wave Springs
• Typical material shown: INCONEL 718 (nickel-based superalloy) — high strength, corrosion and heat resistant (up to ~700°C)
• Thickness range: 0.15 mm – 0.7 mm
• Outside diameter range: 12 mm – 60 mm
• Available part numbers (examples): LM40-H1, LM40-L1, LM40-M1, LM40-H2, LM40-L2, LM40-M2, LM40-H3
• Typical uses: preload, shock absorption, load-bearing, vibration damping in aerospace, medical, automotive, industrial, electronics, oil & gas
• Design features: shim ends for stability and stacking; multi-turn geometry for increased deflection and reduced operating height