Hammer head is an important operational component in crushers, and high-quality wear-resistant hammer heads are the foundation for ensuring the normal operation of crushers and an important guarantee for equipment production efficiency. The lifespan of the hammer depends on its quality and also determines the efficiency of the crusher.
In fact, the lifespan of a hammerhead depends not only on the quality of the hammerhead, but also on the hardness of the crushed material. Red Star Machinery suggests that when choosing a crusher hammer, not only should the wear resistance of the hammer material be considered, but also the performance characteristics of the material to be crushed.
According to experts, the common materials for crusher hammer heads in the mining machinery industry include high manganese steel, medium manganese steel, high chromium cast iron, and low-carbon alloy steel. These hammer heads made of various materials have their own characteristics and advantages and disadvantages. Below, Red Star Machine will explain their specific situations.
1. High manganese steel is a traditional material for hammer heads and a typical wear-resistant steel that is resistant to impact wear. It has good toughness and strong work hardening tendency, and exhibits superior wear resistance under impact conditions. Under the action of significant impact or contact stress, the surface layer will rapidly undergo work hardening, with a work hardening index 5-7 times higher than other materials, resulting in a significant improvement in wear resistance. However, the wear resistance of high manganese steel only shows its superiority when it has sufficient conditions to form work hardening. In other cases, if the physical impact force is insufficient or the contact stress is small and cannot quickly cause work hardening on the surface, the wear resistance is very poor.
2. There is a material that is popular among many mining machinery factories in the manufacturing of hammerheads, which is medium manganese steel that can achieve the use effect of ZGMn13 hammerheads without increasing the price of hammerheads. The actual service life of the medium manganese steel hammer head has been increased by more than 50% compared to ZGMn13, achieving good results in use. The service life of the manganese steel hammer in the as cast state is increased by more than 60% compared to ZGMn13 when crushing sodium feldspar. The biggest advantage of cast manganese steel hammerhead is its magnetism, which can remove iron filings from ore through magnetic separation, ensuring the sintering quality of ceramic products, while high manganese steel does not have this advantage.
3. High chromium cast iron is a wear-resistant material with excellent wear resistance, but it has low toughness and is prone to brittle fracture. In order to ensure the safe operation of high chromium cast iron hammerheads, composite hammerheads have been developed based on this. The high chromium cast iron is embedded in the head of the hammerhead made of high manganese steel or low-alloy steel, or the working part of the hammerhead is made of high chromium cast iron and the handle part is made of carbon steel. The two are combined to make the hammerhead head have high hardness and wear resistance, while the handle part has high toughness, fully utilizing the advantages of both materials and overcoming the disadvantages of a single material to meet the performance requirements. It is reported that in the cement industry, the service life of crushed cement clinker is more than twice that of high manganese steel hammer heads.
4. High chromium cast iron is mainly an alloy structural steel containing chromium, molybdenum and other elements, with high hardness and good toughness, which is suitable for hammerheads to have a high service life. Under the same working conditions, its service life is at least twice that of high manganese steel hammer heads. But its manufacturing process is complex, the process requirements are strict, and the quenching and tempering heat treatment of the hammer head is crucial. After quenching and tempering heat treatment, not only is the overall tensile strength required to reach 850
MPa or above, and requires considerable plasticity and toughness. At the same time, it is strictly prohibited for iron blocks to enter the crusher. A secondary iron suction device is required at the feeding front end, which will also become an important consideration for many users and manufacturers when choosing this material.
In summary, we all hope to find hammer materials with high toughness and hardness, but few hammer materials can balance toughness and hardness. The two are inherently contradictory, and hammer heads are inevitably subject to varying degrees of impact and cutting wear during use. Therefore, when choosing the material of the hammer head, it is necessary to fully understand the working conditions and wear mechanism, and choose the hammer head material reasonably.
Red Star Machine experts also share some tips on how to choose between toughness and hardness for hammer materials.
1. When the hardness of the material is higher, the hardness requirements for the hammer head material are also higher, and the larger the block size of the material, the higher the toughness requirements. Therefore, when choosing a hammer head material, attention should be paid to the block size and hardness requirements of the material to be crushed, which are more important.
2. The larger the size of the crusher, the heavier the hammer head, the larger the block size of the crushed material, and the greater the impact load on the hammer head. Therefore, when choosing the material of the hammer head, the toughness of the hammer head should be ensured first, and then how to improve the hardness of the hammer head should be considered on the premise of ensuring the toughness of the hammer head.
3. In addition to the above two points, there is another important point, which is technology, economy, and effectiveness. It is necessary to be able to put the idea into practice, comprehensively consider the rationality of its process, and take into account the cost-effectiveness of the product, as well as market acceptance and usage effects, striving to achieve high quality, low price, good effect, and market competitiveness.
Choosing the right hammerhead is an important prerequisite and guarantee for equipment production efficiency and enterprise economic benefits. Red Star Machinery selects the appropriate hammerhead material for each crusher to achieve the best matching and usage effect, which is highly sought after in the market. (This article is from Red Star Machine)