What Affects The Service Life of Wear Parts
Common wear parts in crushing equipment include jaw plates, hammer heads, rotors and impact plates. For example, the main wear parts in an impact crusher are the rotor and hammer plates, whilst the wear-resistant components in a sand-making machine are primarily the hammer plates on the impeller, alloy cutting edges, liners and the rotor. The wear-resistant components of jaw crushers are primarily the jaw plates and side liners, whilst the wear parts of hammer crushers are the hammer heads, and those of cone crushers are the concave and concave liners.
The service life of crusher wear parts depends on the combined effect of multiple factors, and the way these factors interact varies across different application scenarios. To maximise performance and minimise downtime, it is essential to understand the causes of wear and how to manage it effectively. These influencing factors can be summarised into four main aspects.
Firstly, the feed material has a significant impact, as rock type, size and shape, crushability, and rock index all influence the rate of wear.
The wear patterns of wear parts vary depending on the material being crushed. The harder the rock, the greater its cohesiveness, and the finer the required particle size, the faster the wear rate of the crusher, and consequently, the shorter the service life of the wear parts. Therefore, selecting the appropriate type and model of crusher based on the comprehensive characteristics of the material is more effective in reducing wear on the wear parts. For example, when crushing granite, using an impact crusher can easily lead to the fracture of the hammer plates; in such cases, a cone crusher should be chosen, as this will prevent excessive wear on its wear-resistant components, such as the concave liner. In the daily operation of jaw crushers, the feed size must not exceed 85% of the equipment’s rated feed opening. If the maximum feed size is 500 mm, the jaw crusher model should be selected as PE-750*1060; one must not select PE-600*900 based on the product specification table, to avoid situations such as material jamming, motor overload, and accelerated wear of wear parts; If the material to be crushed contains a high proportion of impurities, particularly iron blocks and steel bars, this can result in minor issues such as machine jamming, or more serious consequences such as damage to the jaw plates or even cracking of the frame. To prevent this, impurity and iron removal equipment must be installed upstream.
Secondly, the type of liner—including its manganese content (whether 13%, 18% or 22%), profile and overall quality—determines the performance of the manganese liners and other wear-resistant components under pressure. High-manganese steel offers the advantages of moderate hardness, good toughness, impact resistance and resistance to spalling; however, it has the disadvantages of being susceptible to abrasive wear and cutting wear. Consequently, high-manganese steel performs exceptionally well with pure ore and rock, offering a service life 3–8 times that of ordinary carbon steel; however, it is highly disadvantageous for materials containing high levels of impurities, sand, gravel or iron, where the service life of wear parts may be reduced by 30%–70%. In summary, high-manganese steel is not a universal material for wear parts; different materials must be recommended based on specific operating conditions. For example, in applications with high silt and sand content, high-chromium alloys typically extend service life by 1–3 times; where there are high levels of metallic impurities and significant impact, modified high-manganese steel should be used, prioritising toughness, and fitted with a magnetic separator at the front end; for construction waste and complex mixed materials, bimetallic composite hammer heads should be employed to balance wear resistance and crack resistance.
Furthermore, different types of wear—such as abrasive, grinding and chiselling—impose varying degrees of stress on components. Under high-speed scouring conditions involving silt, dust and fine particles, low-stress abrasive wear occurs. As the impact on the surface of the wear parts is insufficient, high-manganese steel cannot undergo sufficient work hardening, resulting in a relatively soft surface. This surface is continuously ‘sanded’ by fine sand, leading to a significant reduction in service life, typically only 40–70% of that under ideal conditions; If, due to excessive size or other factors, materials are repeatedly crushed and subjected to mutual friction within the crushing chamber, this results in medium-stress abrasive wear. This causes the formation of an unstable hardened layer on the surface of the wear parts, manifesting as uniform thinning and the sharpening of rounded edges, with a service life of approximately 60–80% of that under ideal conditions; Under high-stress conditions, large chunks of hard material—such as iron blocks and steel bars—in high-impact crushers can cause chiselling wear, including continuous chipping, fragmentation and fatigue cracks, even though high-manganese steel possesses good toughness and is resistant to chipping and fracture.
Finally, environmental factors (including moisture content and temperature) can also significantly affect the service life of wear-resistant components.
Excessive moisture content in the material can cause it to stick and clump together, forming a cushioning layer within the crushing chamber. This reduces the impact strength, preventing high-manganese steel materials from undergoing sufficient work hardening, and resulting in a significant decline in wear resistance. At the same time, slurry can cause severe corrosion and scouring, exacerbating surface wear, and is also likely to lead to material blockages and overloads, further shortening the service life of wear parts. Ambient and material temperatures similarly affect the service life of wear-resistant components. In low-temperature environments, the toughness of certain steels decreases whilst brittleness increases, making them more prone to cracking and chipping under strong impact; high-temperature conditions may cause the hardness of the wear-resistant layer to diminish, reducing wear resistance, whilst simultaneously accelerating oxidation and thermal fatigue, leading to premature failure of the wear-resistant components.
By taking all these factors into account, DMAC Machinery helps customers extend the service life of wear-resistant components, enabling more efficient and cost-effective operations. 
