Why do so many people choose the impact crusher instead of the hammer crusher?

By: FTM MachineryDecember 05th,2018

Both the impact crusher and the hammer crusher break the material through high-speed impact, and the shapes of the two devices are very similar, so many people cannot distinguish impact crusher and hammer crusher, and don’t know whether to choose impact crusher or hammer crusher. Here, we mainly introduce the advantages of the impact crusher compared with the hammer crusher.

The impact crusher has a unique working mechanism and structural design features. In terms of performance characteristics, the impact crusher has obvious technical advantages compared to the hammer crusher:

1. Uniform particle size, discharge in cubic shape, low fine powder and dust content;

2. Low operating costs and low investment costs. The total weight of the impact crusher is lighter than that of the hammer crusher, its size is smaller, and the dynamic and static load value is lower, which can effectively reduce the civil construction cost. At the same time, the motor power required by the impact crusher is low, which can effectively reduce the power consumption of the equipment and reduce the operating cost of the equipment.

3. The impact crusher has a long service lifespan and low long-term running cost.

Through the above three analyses, the impact crusher has the following five advantages over the hammer crusher:

1. The impact crusher can effectively handle materials with high humidity and prevent the crusher from being clogged.

When the moisture content of the material is too large, the feed chute and the counter plate of the impact crusher may be equipped with a heating device to prevent the material from sticking. What’s more, the impact crusher does not need to be equipped with a bottom sieve plate to effectively prevent clogging. However, the hammer crusher cannot use heating to prevent material bonding and must be equipped with a bottom screen, which increases the likelihood of clogging.

2. The impact crusher is suitable for both soft materials and hard materials.

The hammer of the impact crusher is fixed to the rotor by a mechanical clamping structure, and has a large rotational inertia when the hammer rotates with the rotor. Compared with the hammer crusher, the rotor of the impact crusher has greater kinetic energy, adapts to crushing harder materials, and has lower energy consumption.

3. The discharge size of the impact crusher can be easily and flexibly adjusted, and the adjustment range is wide.

The output particle size of the impact crusher can be adjusted in a variety of ways, such as adjusting the rotor speed, adjusting the backlash and the clearance of the grinding chamber. The gap can be adjusted both mechanically and hydraulically. The hydraulic adjustment system makes it easy to adjust the clearance through the local operation button or the travel control system. However, the discharge size of the hammer crusher can only be adjusted by replacing the bottom screen.

4. The wear rate of wearing parts of the impact crusher is smaller than that of the hammer crusher, and the metal utilization rate is higher.

The wear of the impact plate only appears on the side facing the material. When the speed of the rotor is normal, the material will fall to the surface of the hammer (the striking surface), and the back and sides of the hammer will not be worn. The grinding rod at the bottom of impact crusher is also easy to replace. The metal utilization rate of the impact plate is as high as 45% - 48%. However, the hammer crusher has a suspended state and is subject to wear in all directions. The metal utilization rate of the hammer is only about 25%. Moreover, the rotor body itself may also be subject to wear. The bottom sieve plate of the hammer crusher is seriously affected by the wear, the barrier is completely replaced, and the work of replacing the sieve plate is also complicated.

5. The replacement of the spare parts of the impact crusher is simple and the maintenance cost is reduced accordingly.

Only a few hammers are installed on the rotor of the impact crusher (the equipment of different manufacturers may have different number of hammers). It is convenient to replace the hammer with a special tool. It takes only one shift to replace a set of hammers. The replacement of grinding rod in the bottom grinding chamber can also take only tens of minutes, which greatly reduces the time and cost of inspection and maintenance. However, the hammer crusher has dozens of hammers, and it takes a lot of time and labor to replace a set of hammers, and the maintenance cost is higher. The replacement of the bottom screen is also very troublesome.