Crusher Hammer

The hammer head of hammer crusher is an important part of the crushing machine, and its quality determines the efficiency and service life of the equipment. Therefore, the selection of materials for the hammer head is crucial.

Generally, the hammer head of a hammer crusher is made of high-manganese steel, high-chromium cast iron, or bimetallic composite materials. The selection of material depends on the properties of the crushed material, the type of crushing machine, and the operating conditions.

High-Manganese Steel Hammer Head: High-manganese steel is a common material for hammer heads due to its high toughness, wear resistance, and impact resistance. It is suitable for crushing brittle materials such as limestone, coal, and gypsum, with low compressive strength and high water content. However, high-manganese steel is susceptible to fatigue and wear, and its service life is relatively short.

High-Chromium Cast Iron Hammer Head: High-chromium cast iron has excellent wear resistance, corrosion resistance, and heat resistance. It is suitable for crushing materials with high compressive strength and moderate hardness, such as granite, basalt, and quartz. However, high-chromium cast iron has poor toughness and is brittle, which makes it prone to cracking and fragmentation during operation.

Bimetallic Composite Materials Hammer Head: Bimetallic composite materials consist of two or more materials, with one being the main material and the other being the reinforcement material. The main material can be made of high-manganese steel or high-chromium cast iron, while the reinforcement material can be made of tungsten carbide, titanium carbide, or other wear-resistant materials. Bimetallic composite materials combine the advantages of both materials, with high wear resistance and impact resistance. It is suitable for crushing materials with high hardness, abrasiveness, and toughness.

Wear of the hammer head of the hammer crusher is inevitable, but if the wear is too fast and the replacement frequency is too high, you need to check whether there is a problem with the equipment itself or the operation. The main factors that affect the wear of the hammer head are: the material, manufacturing quality and structural design of the hammer head,Crusher Technical Parameters.
Impact Of Hammer Head Material
The greater the hardness of the hammer, the greater the wear resistance. To improve the wear resistance of the hammer, it is necessary to increase its hardness, but with the increase of hardness, the impact toughness of the hammer will decrease. Therefore, how to give consideration to the appropriate hardness and good impact toughness of the hammer is the key to improve the wear resistance of the hammer.

Hammer commonly used materials are: high manganese steel, high chromium cast iron, low carbon alloy steel.

High manganese steel has good toughness, good processability and low price. Its main feature is that under the action of large impact or contact stress, the surface layer will work hardening rapidly. Its work hardening index is 5-7 times higher than other materials, and its wear resistance is greatly improved. However, if the impact force is not enough or the contact stress is small, the surface can not be hardened rapidly, and the wear resistance of high manganese steel can not be fully developed.

High chromium cast iron is a kind of 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 hammers, people have developed composite hammers, that is, high chromium cast iron is inlaid on the head of high manganese steel or low alloy steel hammers, or the working part of hammers is made of high chromium cast iron, and the handle part is made of carbon steel, The advantages of the two materials are brought into full play to overcome the disadvantages of single material and meet the performance requirements of hammer. However, the manufacturing process is complex and the process requirements are strict.

Low carbon alloy steel is mainly alloy structural steel containing chromium, molybdenum and other elements, with high hardness and good toughness. Its matrix structure includes martensite, bainite or bainite + martensite composite structure. Under the same working conditions, the service life of the hammer is at least twice as long as that of the high manganese steel hammer. However, the quenching and tempering heat treatment of hammer head is the key. After quenching and tempering heat treatment, not only the overall tensile strength is required to be more than 850mpa, but also considerable plasticity and toughness are required.
Certifications

The Manufacturing Quality Of The Hammer
The manufacturing process of hammer head is also the key factor to determine its service life. If there are defects in the surface or internal manufacturing of the hammer head, such as shrinkage and cracks, it will not only reduce the performance of the hammer head, but even cause the hammer head to break. Therefore, reasonable casting and heat treatment process must be established in hammer production.

For high chromium cast iron hammerhead, measures such as vertical casting, rational use of external chill and strict control of casting temperature should be adopted, so that the hammerhead can have good solidification sequence and feeding conditions during casting, thus obtaining dense internal structure and weakening the phenomenon of coarse grain.

The Structure Design Of The Hammer Head
The mechanical properties and internal microstructure of hammers with different structures and geometric shapes are very different, which has a great influence on the wear resistance, especially for hammers with large thickness and size. The thicker the hammer head is, the harder it is to harden, and the worse its wear resistance is.

As the internal anti-wear performance of the hammerhead is obviously lower than that of the surface, it can only be improved by reasonable casting and heat treatment process for the hammerhead with larger thickness. However, this method is limited to improve the anti-wear performance of the hammerhead.

The best way is to optimize the structure of the hammerhead without changing the impact kinetic energy and strength of the hammerhead, On the one hand, it can improve the utilization rate of the hammer, on the other hand, it can reduce the influence of the structure on the heat treatment performance and avoid the decline of the wear resistance of the hammer.

Crusher Technical Parameters
The life of the hammer is also related to the technical parameters of the crusher, the most important of which is the power and speed of the rotor. These two parameters directly reflect the linear velocity and impact force of the hammerhead. They are not only related to the production capacity of the crusher, but also to the degree of impact hardening of the hammerhead.

The hammer with good impact hardening will have a prolonged service life. The rotor speed is too low, not only the low production capacity, but also low kinetic energy, resulting in poor hammer impact hardening and poor wear resistance; the rotor speed is too high, although the hammer can obtain better impact hardening and equipment productivity, but also The hammer head, the stringer and the lining plate are strongly worn, which is also detrimental to the service life of the hammer head, and at the same time, the power consumption is significantly increased.