The content of machine-made sand and gravel powder refers to the content of sand particles smaller than 0.16mm in the finished product. Particles smaller than 0.08mm can be regarded as an inert admixture:
The hammer crushing sand making machine is reasonably adjusted, and there will be no phenomenon of high powder yield:
1. Excessive content of stone powder will affect the strength and compactness of concrete.
2. Appropriate stone powder content can improve the workability of concrete, improve the compactness of concrete, and is beneficial to improve the performance of concrete. Many large-scale artificial sand and gravel systems in China have insufficient rolling stone powder content, or some engineering sand and stone powder content exceeds the standard. Generally, the stone powder content of sand and gravel materials used in projects is required to be controlled at about 6-18%, and the stone powder content of roller compacted concrete sand. The requirement is controlled between about 12-22%.
Then the reasons that affect the high powder output rate of the hammer crusher are as follows:
1. The hammer head is seriously worn: the hammer head is the main working part of the hammer crusher. It is easy to wear during the blowing operation of the material. When the hammer end of the hammer head is worn to 1/3 of the hammer head, it will It is easy to produce the situation that the discharge particle size is too large and the shape of the material is not good; solution: It is recommended that you use a high-chromium alloy forging hammer to replace the traditional ordinary hammer. The life of the hammer is 3-4 times that of the ordinary hammer. The alloy hammer used not only saves a lot of parts costs, but also saves a lot of production time wasted by frequent replacement of the hammer.
2. The hammer disc is worn or damaged: the hammer disc is the main structure of the rotor, which plays the role of protecting the hammer head. When the hammer crusher operates at high intensity or is impacted by large pieces of material, the hammer disc is prone to wear or damage, and is easily damaged. The worn hammer disc is easy to cause some hammer heads in the row of hammer heads to produce the phenomenon of chucking, that is to say, some hammer heads cannot be hammered normally, and the impact force on the material will also cause the equipment to produce powder. The phenomenon that the rate is too high; solution: We can install a retainer on the edge of the hammer plate to widen and thicken the hammer plate to improve its degree. When the hammer disc is cracked or seriously damaged, we need a new hammer disc.
3. Wear and tear of grate bars: traditional hammer crushing sand making machines mostly use grate bar discharge ports, that is to say, materials that meet the discharge size will be discharged through the gaps of the grate bars. If the gap is too large, or if it is directly broken, the direct consequence is that it is impossible to control the discharge particle size, which makes the material discharge particle size too large. Solution: Replace the grate plate. The grate plate is the same wearable part as the hammer head in the hammer crushing sand making machine. To solve this problem, we can replace the traditional grate plate outlet with an adjustable lining plate. The tightness adjustment can realize the control of the discharge granularity, and avoid the occurrence of the material blocking the grate plate or the wear and tear of the grate plate.
4. Screen hole adjustment of vibrating screening machine: round, linear, diamond and other screening machines will directly affect the quality of the finished product of the hammer crusher.
