The requirement of pebble sand making machine for sand making material is fine particle. Usually, for needle-like materials, they need to enter the fine crusher cabin for crushing. However, for crushed stone, there are strict requirements for its particle shape and grade. This is because the cubic sand particles have angles that make them form an interlocking effect with each other. At the same time, the continuous gradation of the sand significantly reduces the presence of pores. In addition, square sand has a larger surface area than round sand, which allows asphalt or cement to bond to the material, thus reducing the possibility of displacement.

When stone that cannot be finely crushed enters the crushing chamber of a pebble sand making machine, a rear thrust plate is often used as a safety component in order to protect important parts of the machine from damage. The rear thrust plate is sometimes made of integral cast iron with slots or a number of small holes in it to reduce its cross-sectional strength. It can also be cast into two pieces and then connected with screws to form a combined thrust plate. When the sand making stone that cannot be finely crushed enters the fine crushing chamber, the equipment will be overloaded, which will be transmitted to the thrust plate, causing the thrust plate to break or the screws on the combination thrust plate to break, thus stopping the machine and acting as a protection. This design principle is not only very applicable, but also easy to control, low cost to replace the safety parts, easy to operate, and also helps the overall maintenance of the equipment and avoid damage.