The crusher hammer head, the accurate definition should be the hammer crusher hammer head, the hammer head is one of the core components of the hammer crusher, arranged on the hammer shaft of the crusher rotor, the hammer head directly hits the crusher at high speed The material is finally broken into the appropriate material size.
Basic introduction
The crusher hammers on the market can be divided into two types according to the manufacturing process: casting and forging, but their wear resistance is different. Due to the broken material, the head needs good wear resistance and the handle needs sufficient toughness. It is usually formed by forging or casting with alloy steel, high manganese steel, cast steel and high chromium cast iron bimetal composite. The corresponding heat treatment process is more economical. The crusher hammer can be divided into kinds according to the material: high manganese steel hammer head, bimetal hammer head, composite hammer head, big gold tooth hammer head, medium chromium alloy hammer head, hard alloy Hammer head, etc. The main factor is the content of silica. The technology under modern industry shows that the use of cemented carbide hammers performs well in wear resistance.
Hammer head classification
Folding forged hammer.The forging crusher hammer is suitable for crushing pebbles, coal gangue, limestone, etc. Forging crusher hammer head is made of high quality train wheel steel (material 65Mn, good impact resistance, strong toughness, good wear resistance, not easy to break). Forging machine is used for repeated forging by metal forging to obtain certain mechanical properties. A certain shape and size, after a special quenching heat treatment method, to ensure high hardness and high wear resistance of the working area of the hammer. Through forging can eliminate defects such as as-cast looseness caused by metal in the smelting process, optimize the microstructure, and at the same time, the mechanical properties of the forgings are generally superior to those of the castings due to the preservation of the complete metal flow lines. Forging hammers are favored by users because of their low price, economy and durability.
Folded high manganese steel hammer.Alloyed high-manganese steel wear-resistant hammer head, reliable quality, wear resistance is three times that of traditional high-manganese steel. The crusher hammer is widely used in large-scale limestone crusher supporting domestic new dry process cement production line.
Mn13, Mn13Cr2 and Mn18Cr2. It is suitable for strong impact conditions such as tooth plates, rolling walls, broken walls and large excavator teeth of large and medium-sized crushers. It can also be used as a ball mill, a semi-autogenous mill, and a self-grinding liner.
With the continuous development of wear-resistant materials, high-manganese steel has gradually become unsuitable for the development of the modern foundry industry. Replaced by chrome molybdenum alloy steel, high chromium cast iron and nickel hard cast iron. However, the high toughness characteristics of high manganese steel are unmatched by other wear resistant materials.
The high manganese steel crusher hammer has good toughness, good manufacturability and low price. Its main feature is that under the action of large impact or contact stress, the surface layer will quickly produce work hardening, and its work hardening index is higher than other materials. -7 times, the wear resistance is greatly improved. However, the hammer head of the high manganese steel crusher has high requirements on the overall performance of the crusher. If the physical impact force is insufficient or the contact stress is small in actual work, the surface cannot be hardened by work hardening, so that it does not exert its proper wear resistance. Sex. Therefore, the majority of customers should be selected according to the actual parameters of the equipment before use, and if necessary, the equipment can be modified to maximize economic benefits.
Folded high chromium alloy hammer.The sorghum alloy crusher has excellent hardness and is a high-quality wear-resistant material. It has been widely used in fine crushers (third-generation sand making machines) and impact crushers that support hammer frames, but high chromium alloy toughness. Poor, it is prone to breakage without the support of the hammer frame. The high-chromium composite hammerhead, that is, the hammer handle uses high-manganese steel, the hammerhead working area uses high-chromium alloy, and the two are combined to make the hammer head have high hardness, and the hammer handle has high toughness, and the two types are fully utilized. The respective advantages of the material overcome the shortcomings of a single material and meet the performance requirements of the hammer. It is especially suitable for crushing high hardness materials such as quartz stone and basalt. However, its manufacturing process is complicated, the process requirements are strict, and the price is high.
Folding carbide hammer.Compared with other materials, the hard alloy hammer has higher hardness, flexural strength and impact, heat fatigue resistance, good heat hardness and low cost. It solves the cracks and desoldering of high manganese materials. Problems such as collapse, falling blocks, etc.
1. Ultra-high wear resistance is more than 20 times that of high manganese steel hammer
2. It has good resistance to mechanical shock and thermal shock.
3, a wide range of applications, basically can be adapted to all the crushing industry.
Cause of damage
The crusher hammer is prone to breakage and wear, resulting in a variety of reasons:
1. The feed size is seriously above the maximum limit.
2. When the hammer is cast, the quality is inaccurate.
3. The accumulated material inside the crusher was not cleaned in time, and the hammer was subjected to severe wear when it was started again.
Performance characteristics
1. The impact on the material has increased. Since the center of gravity of the hammer crusher hammer moves outward in the radial direction of the radius of gyration, the hammer speed increases during operation. The impact energy of the hammer crusher hammer on the material is increased, thereby improving the crushing effect.
2. The effective wear amount of the hammer crusher hammer head is increased. The hammer weight is generally calculated as 27 kilograms, and the effective wear amount is one-third, that is, 9 kilograms. The improved overall weight change of the structure is small, and the effective wear amount is 16 kg. The improved hammerhead is equivalent to the two sets before the improvement, which reduces the cost of use.
3. Reduce the discharge size and increase the production time. After the improvement, the length from the end of the suspension hole to the end of the hammer is from 350 mm to 360 mm, the diameter of the rotation is about 1250 to 1270 mm, and the clearance from the hammer to the shell of the hammer crusher is reduced from 25 mm to 15 mm. Therefore, the discharge particle size can be changed from the original 20 mm or less, 25% powder to 8-10 mm, 60% powder, which greatly improves the crushing effect of the crusher, thereby improving the production time of the crusher. .
4. Improved grinding effect. After secondary crushing of materials such as limestone, it is necessary to study energy consumption and efficiency. The crushing efficiency is higher than the grinding efficiency and the power consumption is small. Therefore, it is required and hoped that the limestone will be broken and less polished. The discharge size of 8-10 mm, 60% of the powder, greatly improved the production effect of the powder machine. The output is 16 tons per hour and 16 tons per hour, which reduces the production cost of raw meal.
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. At the same time, it will also cause strong wear of the hammer, the purlin and the lining, which will also be detrimental to the service life of the hammer, and will significantly increase the power consumption. Therefore, a reasonable rotational speed should be determined to improve the degree of impact hardening at the initial stage of the hammer work and reduce the wear of the hammer.
Feeding conditions include: 1 feeding size and hardness; 2 feeding mode of hammer crusher. The former is related to whether the crusher will encounter the impact impulse when the material and the hammer hit the material. The latter will cause the difference of the material to the rotor due to the different feeding modes, and also affect the impact impulse when the hammer hits the material. When the weight of the hammer and the rotor speed are constant, the collision impulse of the hammer is proportional to the material quality and the drop, and the magnitude of the collision impulse is directly related to the degree of work hardening and wear resistance of the hammer. Therefore, the particle size of the large hammer crusher should not be too small, and the speed of the feeding equipment should be higher. Also. Excessive moisture content of the material will also have a certain impact on the life of the hammer. If the water content is too high, the materials are easily bonded into a mass, which causes accumulation of materials and aggravates the wear of the hammer.
Service life
1. According to the design model, the feed size should be properly controlled, and it is strictly forbidden to enter the machine beyond the design maximum size.
2. Select suitable feeding equipment, such as feeding with plate feeder or vibrating feeder to ensure uniform and stable feeding, avoiding impact on equipment and ineffective operation due to uneven feeding.
3. Due to the error in the quality of the hammer casting, the hammer should be reversed and turned according to the current in the process of use, so that the hammer is evenly worn and the rotor is balanced.
4. It is best to weigh the new hammer when it is replaced. It is divided into several groups according to the average quality. The quality requirements of each group are equal. Otherwise, the rotor imbalance will cause vibration when starting.
5. Check the gap between the hammer head and the screen bar, between the screen bar and the screen bar when parking, adjust if necessary, and replace the screen bar regularly. Because the cost of the hammer is higher than that of the sieve, the new sieve can use 4-5 more hammers than the old sieve.
6. The hammer frame of the hammer crusher is made of cast steel and has less contact with the material. However, when the metal or the lining plate falls into the crusher, it is easy to cause damage or bending of the middle hammer plate. Drop, otherwise it is easy to lose the hammer and cause vibration.
7. The edge hammer disc of the hammer frame and the side plate of the casing are subjected to material impact, and the wear of the hammer disc is serious. In order to extend the service life of the side disc, it can be welded on the circumferential surface of the side disc and the side near the side panel. Wear layer.
8. Due to the friction during operation, the shaft diameter at both ends of the spindle is easy to wear. When installing, add two bushing sleeves at the shaft diameter to protect the shaft diameter on the shaft.
9. After the bearing wears, it must be repaired and withered in time. After the bearing is worn, the bearing bush should be scraped according to the new size, and the thickness of the gasket should be adjusted to maintain a reasonable gap to form an effective lubricating film.
10. The power and speed of the rotor, in addition to directly related to the production capacity of the crusher, is also related to the degree of hammer hardening, to extend the life of the hammer of the crusher, but also to distinguish the material of the hammer, for high manganese steel The hammer of the material must be ensured that it has a large enough impact force, but for the high-chromium hammerhead, it is just the opposite, it must be controlled to have no excessive impact.
11. It is necessary to regularly clean the accumulated parts of the crusher. Because of the accumulation of materials, the hammer of the crusher will be subjected to severe friction and wear and the service life will be drastically reduced.
