The science of wear control is extremely complex. Lund recognized early on that all wear is not the same, and by extension
that there is no single best solution for all wear problems. While Lund’s technical expertise and developments include all facets of the design and manufacturing process, the core of its efforts is the development of hard coatings and inlays that can be bonded to steel. The goal is to continue to provide ever-greater utility per unit of cost, and deliver precision parts of exceptional quality.
Lund specializes, in particular, in cutting system wear and abrasive wear. We produce wear and cutting system parts that have extended wear life designed in. Working closely with equipment manufacturers' engineers, Lund first seeks to gain a comprehensive understanding of the application. Then, we sort through the various considerations attendant to the problem to come up with the optimal solution. Those considerations include:
Material selection is the first step in the process of manufacturing the cutting system or wear part. With the information gathered from field testing, Lund engineers are able to select a base steel that will optimize such factors as strength, durability, cost, availability and cost effective manufacture. One material that often meets all of these design criteria is a medium carbon, chrome-molybdenum alloy steel. The combination of carbon, manganese, chrome and molybdenum results in a steel that has excellent strength characteristics as well as superior wear and corrosion resistance.
Cutting System Wear
Cutting system wear is essentially “dullness” of the cutting system. If the system is not kept sharp, the quality of the material being cut suffers, throughput is reduced, more energy is needed to operate the system, more heat is generated, etc.
In general, the harder the cutting edge, the longer it will remain sharp. Unfortunately, similarly the harder the edge the more brittle and susceptible it is to breakage. Therefore, in many of Lund’s products the cutting edge is selectively hardened, while the body of the part is maintained at a lower, tougher, more ductile state.
Lund pioneered the use of tungsten carbide hard coatings on its knives more than thirty years ago. The application of a thin coating of tungsten carbide to a knife edge established two levels of hardness on the working part of the knife. The tungsten carbide is even harder than the hardened edge of the steel. This differential in hardness creates a subsystem on the knife that causes the knife to actually wear itself sharp. That is, the hardened edge of the underlying steel wears slightly faster than the harder tungsten carbide coating, thus maintaining a sharp edge. This results in Lund's well-known "WEAR SHARP" edges.
Keep in mind, however, that the thinner the tungsten carbide coating, the sharper the edge remains. In other words, it can never get sharper than the thickness of the hard facing material. Unlike its competitors, Lund’s approach to tungsten carbide edge treatments is to use very small tungsten carbide particles that can be closely packed in a relatively thin coating, as compared to large chunks in a thick coating (Large chunks also suffer from their susceptibility to be dislodged by impact, thereby leaving a large, wear inducing void).
Abrasive wear is due to hard particles being forced against and moving along a solid surface, or hard protuberances on one solid surface being forced along another solid surface. Such wear can occur in almost any environment, including in soil, in air with abrasive particles, in liquids with abrasive particles, etc. The two principal requirements of any coating that is intended to resist wear are that it must be hard (the harder the better, subject to impact resistance constraints) and it should be as smooth as possible.
Lund’s proprietary WEAR-TUFF ® coating is specifically designed to meet these requirements. And, since it can be applied either as a slurry or sprayed on, it is a very economical process, especially in a production environment.
Other Types of Wear
There are several other mechanisms of wear, including adhesion, erosion, and corrosion. Often, more than one mechanism occurs at the same time. Corrosion is an especially complex problem. However, one of Lund’s wear resistant technologies can typically solve even the most difficult problem.