Flat Spring Washers – also known as conical or Belleville washers – deliver high spring force within an extremely low axial height. Their conical shape actively maintains bolt preload under vibration, thermal cycling, and material creep. Unlike flat washers that only distribute load, these washers store mechanical energy and compensate for joint relaxation. Manufactured from spring steel or stainless steel with optional corrosion-resistant coatings, they provide a compact, cost‑effective solution for bolted joints that must stay tight.
| Parameter | Details |
|---|---|
| Shape | Conical disc (Belleville) |
| Outer Diameter | 3 mm – 100 mm+ (M3 – M100+) |
| Inner Diameter | 1.5 mm – 70 mm+ |
| Thickness (t) | 0.2 mm – 20 mm |
| Free Cone Height (h₀) | 0.3 mm – 30 mm |
| Materials | Carbon spring steel (51CrV4, CK75), Stainless (301, 304, 316), Alloy steel (high temp) |
| Surface Finishes | Zinc plated, Dacromet, PTFE, Xylan, nickel plated, phosphated & oiled |
| Load Range | 10 N – 500,000+ N (depending on size and stack) |
| Deflection | 10% – 75% of free cone height |
| Stacking Options | Parallel (load increases), series (deflection increases), parallel+series |
| Operating Temp. | Carbon: -40°C to +300°C / Stainless: -200°C to +500°C |
| Standards | DIN 2093, GB/T 1972, ASME custom |
| Testing | 100% load test, MPI, dye penetrant (upon request) |
| Traceability | Mill test reports, EN 10204 3.1 |
Flanged joints under thermal cycling rely on these washers to maintain gasket compression when bolts expand or relax.
Petrochemical and refinery piping flanges
Steam lines and heat exchanger covers
Boiler manways and handhole closures
Exhaust system connections in heavy vehicles
High-pressure gas pipeline flanges
Heavy machinery and vibrating equipment use flat spring washers to prevent loosening under dynamic loads.
Mining crushers and vibrating screens
Compressor and pump housing bolts
Wind turbine tower and hub flanges
Railroad rail fastening systems
Agricultural machinery subjected to field vibration
Electrical and power applications benefit from constant contact pressure over wide temperature swings.
Bus bar and electrical panel connections
Transformer tank cover bolts
Switchgear and circuit breaker mounts
Generator stator bolted joints
Battery terminal connections
Valves and actuators demand preload retention under pressure cycles.
Control valve bonnet bolts
Actuator yoke and bracket connections
Safety relief valve flange studs
Hydraulic manifold mounting
Pneumatic cylinder end cap fasteners
Automotive and transportation require vibration-resistant fastening in confined spaces.
Transmission clutch pack washers
Engine timing chain tensioner bolts
Differential bearing preload adjustment
Brake caliper mounting brackets
Suspension component fasteners
Choose Flat Spring Washers for active joint security and long‑term reliability without complex systems.
Space efficient: Achieves high spring force with very low solid height – ideal for tight assemblies.
Vibration proof: Absorbs dynamic loads and prevents nut loosening caused by machinery operation.
Thermal compensation: Maintains bolt preload when temperature changes cause expansion or contraction.
No re‑torquing needed: Eliminates repeated tightening after gasket settling or bolt relaxation.
Customizable performance: Stack in parallel to increase load, in series to increase deflection, or combine both.
Predictable spring rate: Progressive load curve matches increasing bolt stretch under pressure.
Material versatility: Carbon, stainless, or alloy steel with corrosion‑resistant coatings for any environment.
Easy installation: Directly replaces flat washers – no special tools or training required.
Long service life: Engineered for millions of cycles without fatigue failure.
Cost effective: Low cost per joint compared to hydraulic tensioning or coil springs.
Each Flat Spring Washer delivers specific mechanical actions that solve real bolted joint problems.
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Conical deflection: Flattens under load, storing mechanical energy that pushes back against the bolt head or nut.
Preload retention: Maintains clamping force after external forces cause bolt stretch or joint compression.
Shock absorption: Compresses instantly under impact loads, protecting bolt threads from stripping.
Vibration dampening: Converts vibrational energy into small elastic movements rather than allowing rotation.
Thermal expansion management: Expands or compresses as joint temperature changes, keeping gasket compression constant.
Creep compensation: Gradually relaxes to take up space when soft gaskets or plastic materials settle.
Parallel stacking: Multiple washers stacked same direction multiply load without changing deflection distance.
Series stacking: Washers stacked opposite direction increase deflection travel without changing load.
FAQ
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2. How long is your delivery time?
Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.
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Yes, we could offer the sample for free charge but need pay the cost of freight.
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