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Hardness Means Durability – Lapua Ultra Chains Deliver Long Service Life Even in Demanding Conditions

Lapua Ultra chains are designed for applications subject to extremely heavy wear. The product family includes chains treated with the Lapua Hybrid® hardening method as well as through-hardened chains. 

Lapua Hybrid® hardening 

Lapua Hybrid® is Lapua Chains’ proprietary hardening method, developed especially for smaller chain sizes (M56–M160). The method combines the best characteristics of case hardening  and through hardening, giving the chains exceptional wear resistance. 

High resistance to mechanical wear is particularly important in riveted chains operating at high speeds. Lapua Hybrid® provides the required durability by hardening the material throughout while also creating a highly wear-resistant surface layer. 

– Products that are only surface-hardened wear slowly at first, but once the wear-resistant surface layer has worn through, chain elongation increases rapidly and the chain soon needs to be replaced. A Hybrid-hardened chain wears in a more linear and predictable manner, without sudden increases in wear or elongation, explains Tomi Ulvila, Quality and IT Manager at Lapua Chains. 

Through hardening 

Through hardening is particularly well suited to larger chain sizes (M224–M900). A through-hardened bush can withstand high contact pressure without cracking and is designed for chains subjected to continuous heavy loads. Lapua Chains has extensive research and testing experience in through-hardened chain components. 

– There is a common misconception that through hardening makes a chain brittle. This is not the case. Through hardening makes the chain components extremely strong against the pressure generated by the sprocket. We have studied this and verified it through testing, Ulvila explains. 

The key strengths of the Lapua Ultra product family 

• Pins and bushes are hardened throughout, providing a significantly greater wear reserve compared with surface-hardened components. As a result, elongation caused by wear in the chain joints develops more slowly, and the chain requires considerably less maintenance than surface-hardened chains. 
• Precision cylindrical holes for pins and bushes are machined into the side plates, ensuring a secure and stable chain construction. 
• Thanks to their material properties, the side plates offer excellent weldability without losing their essential properties, making the chains highly serviceable and repair-friendly. 
• Through hardening helps prevent bush cracking. 
• Only raw materials of known origin from Western suppliers are used. 
• The products offer excellent resistance to low temperatures. 
• Tight press fits increase fatigue strength and breaking strength. 

In addition:

• In chain sizes M224–M900, the pins and bushes are welded, increasing breaking strength by 40%.
• In riveted chains, the pins and bushes feature double flats. These prevent the pins and bushes from rotating and significantly improve chain durability. The double-flat design also creates a supporting shoulder against the side plate, enabling very strong and reliable joints. 

Lapua Chains aims to provide maximum service life with the Lapua Ultra product family. 

Read more about the strengths of the Lapua Ultra product family: 12 competitive advantages. 

Lapua Chains also offers a product family designed for lighter-duty applications: Lapua Standard.