First, on the premise of selecting a high-quality ring die, the appropriate die hole form, opening ratio and shrinkage ratio (tightening ratio = useful length of die hole diameter of the die hole) should be selected according to the specific gravity of the product. Under the premise of ensuring the strength of the ring die, try to improve the opening ratio of the ring die. For some kinds of materials, under the condition of ensuring a reasonable tightening ratio, the ring die is too thin, resulting in the strength of the ring die, and the explosion will occur during production. In the die phenomenon, the thickness of the ring die and the opening of the pressure reducing hole should be increased under the premise of ensuring the useful length of the die hole.
The ring die tightening ratio refers to the ratio of the useful length of the ring die hole to the minimum diameter of the ring die hole, which is a target reflecting the kneading strength of the wood chip particles. The greater the tightening ratio, the stronger the extruded wood pellets. Regarding the ring die tightening ratio of the straight hole, the useful length of the ring die hole is the total thickness of the ring die, and the minimum diameter is the diameter of the die hole itself; regarding the release stepped hole and the outer tapered hole, the die The useful length of the hole is the total thickness of the ring die minus the length of the release hole or the length of the outer tapered hole. The aperture of the small diameter segment is the aperture for calculating the tightening ratio; for the compact stepped hole and the inner tapered hole, This situation is quite special. Generally, the thickness of the entire ring die is taken as the useful length of the die hole, and the minimum diameter is taken as the diameter of the small diameter segment. Of course, the meaning of the calculated ring die tightening ratio is different from the first two cases.
Roughness is also an important target for measuring the quality of ring dies. Under the same tightening ratio, the greater the roughness value, the greater the extrusion resistance of the wood chip, the more difficult the discharge is, and the excessive roughness also affects the quality of the particle appearance. A suitable roughness value should be between 0.8 and 1.6.
The company has a large CNC die punching center, a pellet machine assembly and testing center, a large blank forging base, an assembly line manufacturing base, and a pellet production test center. The products are subject to strict quality control from raw material procurement, parts processing, heat treatment, welding assembly, to finished product delivery. The company will recommend the appropriate biomass pellet machine according to the customer's needs, and will never force it for recommendation. Believing in the power of quality and providing quality services has always been the corporate principle of Jiangsu Kingwood!