High Strength Shock Absorber Coil Spring

XiaYi High Strength Shock Absorber Coil Spring uses alloy spring steel and controlled forming processes to achieve consistent spring dimensions and stiffness. The design can be matched with different shock absorber assemblies according to vehicle weight, axle load, suspension space and expected operating conditions.

The spring can be supplied for original equipment production, replacement parts and suspension upgrades. Different wire diameters, coil diameters, free lengths and spring rates can be developed according to drawings or sample springs.

Load & Spring Rate

The load capacity of a suspension spring depends on material strength, wire diameter, coil diameter, active coils and overall geometry. XiaYi controls these factors during forming to help maintain consistent spring force between batches.

For passenger vehicles and EVs, spring specifications can be adjusted according to curb weight and battery weight. For commercial vehicles and machinery, the spring design can focus more on continuous loading, impact conditions and higher axle loads.

Spring stiffness is also matched with the shock absorber. Excessively soft springs may cause greater suspension compression, while excessively stiff springs can reduce suspension compliance on uneven roads. XiaYi therefore develops spring specifications according to the actual suspension requirements rather than using one specification for different vehicle applications.

Production Process

The production process is designed around spring geometry and fatigue performance rather than simply increasing material hardness.

Material Selection

XiaYi uses 60Si2Mn, Cr-Si and Cr-V alloy spring steel according to the required load and application. The selected material provides the tensile strength and elastic characteristics required for repeated compression and rebound cycles.

Heat Treatment

Controlled quenching and tempering stabilize the metallurgical structure of the spring. Finished hardness is maintained at approximately HRC45--52 according to the product specification, helping balance strength and elasticity.

CNC Coiling

Automatic CNC coiling equipment controls outer diameter, pitch and free length. Typical control values include ±0.2 mm for outer diameter, ±0.1 mm for pitch and ±0.5 mm for free length.

Stress Relief

After coiling, controlled stress-relief treatment reduces residual stress generated during forming. This helps limit permanent deformation and changes in spring height during extended service.

Shot Peening

Full-surface shot peening introduces compressive residual stress into the spring surface. This process helps slow fatigue crack initiation when the spring repeatedly operates under compression and rebound loads.

End Grinding

The spring ends are precision ground to provide stable contact with the spring seat. End flatness can be controlled to ≤0.03 mm, helping distribute load more evenly after installation.

Key Parameters

Product Comparison

Vehicle Matching

Different vehicles require different spring characteristics. XiaYi High Strength Shock Absorber Coil Spring can be developed according to vehicle weight, axle load and suspension structure.

For passenger cars, the focus is generally on balancing load support and ride comfort. EV applications require additional consideration of battery pack weight and its influence on front and rear axle loads.

For SUVs and light commercial vehicles, higher load variation requires a spring with stable stiffness under repeated loading. Heavy commercial vehicles and construction machinery require higher load capacity and better resistance to impact fatigue.

Application Cases

EV SUV Project

In 2025, a domestic EV brand used customized XiaYi High Strength Shock Absorber Coil Springs for a medium-sized pure electric SUV. The original springs showed noticeable body sagging after approximately 30,000 km because of the vehicle's high battery load.

After replacing them with XiaYi alloy springs with optimized stiffness, road testing showed no measurable body sagging after 80,000 km. The lateral roll angle decreased by 22%, while the 500-hour salt spray coating provided additional protection for vehicles operating in humid coastal areas.

Loader Project

A construction machinery company replaced imported springs on its 5-ton loader with XiaYi heavy-duty springs. The original springs had an average replacement cycle of less than six months under repeated impact on gravel construction sites.

After using Cr-V alloy springs with full shot peening, the service cycle increased to more than 14 months. The customer's replacement cost decreased by nearly 45%, while abnormal vibration and operating noise were also reduced.

Delivery Fleet

A city logistics fleet replaced the original suspension springs on its delivery vans with XiaYi springs. The vehicles frequently operated under full-load cargo conditions, causing elastic attenuation and uneven tire loading.

After replacement, spring support remained more consistent under full load. The fleet reported a 38% reduction in unilateral tire wear, helping lower tire replacement costs.

Customization

XiaYi supports customized spring development for OEM and aftermarket applications.

Customers can provide drawings, samples or basic vehicle information such as vehicle model, curb weight, maximum load, axle load and installation dimensions. The technical team can then determine the appropriate wire diameter, outer diameter, free length, number of active coils and spring rate.

For fleet and machinery applications, the spring can also be adjusted according to working load, road conditions and operating frequency.

Installation Notes

The spring should be installed together with compatible shock absorbers and spring seats. Before installation, confirm the free length, outer diameter, end shape and mounting position.

After replacement, four-wheel alignment should be performed when required by the vehicle suspension design. Springs on the same axle should normally be replaced as a matched pair to maintain balanced suspension height and load distribution.

FAQ

Can the spring rate be customized?

Yes. XiaYi can customize spring stiffness according to vehicle weight, axle load, suspension travel and customer drawings or samples.

Is it suitable for EVs?

Yes. The spring can be developed for EV suspension systems by considering the additional battery weight and front/rear axle load distribution.

How long can it last?

Service life depends on vehicle load, road conditions, suspension design and maintenance. XiaYi products undergo fatigue verification of at least 1 million cycles to evaluate long-term elastic performance.

Can small batches be customized?

Yes. XiaYi supports both OEM mass production and customized orders. Specifications, materials, dimensions and spring rates can be adjusted according to the application.

Quality & Supply

XiaYi has established a quality management system compliant with IATF 16949:2016 and controls material inspection, forming, heat treatment, surface strengthening and finished-product testing throughout production.

As a professional China manufacturer, XiaYi provides customized suspension springs for automotive OEMs, aftermarket suppliers, commercial vehicle manufacturers and construction machinery companies. Batch inspection records and product test data can be provided according to customer requirements.