The roller granulator uses two relatively movable rollers for extrusion molding. There is a certain gap (adjustable) between the two rollers and the two rotate at the same rotation speed. One set of roll shaft seats is fixed and the other set of roll shaft seats is slid to help the cylinders press each other against each other. Casting steel roller shell is a good choice. The surface of the roll is regularly arranged with many arc grooves of the same shape and size. The two rolls are horizontally parallel. The powdery granular material is continuously and evenly weighed on both rolls and pressed between the rolls by a forced feeder to roll granulation. The machine is formed under the high pressure of two rollers. Next, it enters the shredding device to break the pellets, and then the screening machine sifted out the finished granules. The screened out defective products can be put into the feeding port again for secondary granulation. The shape of the particles depends on the shape of the groove on the surface of the roller (e.g. oval, sheet or strip). We provide customized roller shell with wholesale price and high quality.