Mineral sizers tooth structure fastening method diagram, the tooth crown and tooth ring seat of the door (shape) structure are bolted together, the tooth crown is welded with a wear-resistant layer. Mineral sizers tooth structure fastening method schematic diagram, fluted structure teeth from the crushing roll tooth damage, crushing roll teeth break phenomenon, and crushing roll teeth and tooth base joint surface adhesive material.
The reasons are as follows: First, the fastening mode of the crushing tooth structure is unreasonable and there are contradictions, which makes the stress state of the crown of the tooth and the clamping state of the bolt bad, resulting in a bad stress state, and easy to break when subjected to a large impact or difficult to break materials; Second, there are defects in the manufacturing of crushing roll teeth, which lead to the accurate joint of crushing roll teeth and tooth base, and the stress state of crushing roll teeth is not good. From the operation of mineral sizers, the tooth crown is covered by a wear-resistant shell, which has good wear resistance. The shell is a wearing part and is damaged in normal use.
Based on the broken teeth, the structure of the tooth crown has been improved by changing the door structure of the tooth crown to a groove shape, which is not easy to break teeth. The force state of the tooth crown and the state of the bolt are not good. The reasons for the contradictions in the fastening methods of the above two crushing teeth structures are analyzed as follows: When the bolt is not fastened, the two sides of the tooth ring seat and the tooth crown are interstitially fastened due to assembly needs, and when the bolt is fastened through the tooth crown and the tooth ring seat, after the bolt is fastened through the bolt hole, the pretightening force of the bolt only acts on the tooth crown of a single part, that is, the two external measuring surfaces of the tooth crown of the portal structure. Due to the large crushing force, the tooth crown is a door-shaped structure with great strength and stiffness. After the tooth crown is joined by bolt connection, the tooth crown will not produce enough elastic deformation to completely eliminate the matching gap between the two sides of the tooth crown and the tooth ring seat.
The bolt can only be closely matched with a single tooth crown, so the tooth crown and the tooth ring seat cannot be completely fastened. Due to the gap between the mineral sizers bolt and the ring seat, the crown of the tooth will repeatedly slide relative to the ring seat when it is broken, resulting in wear on the mating surface, which further increases the mating gap. Replacing the crown of the tooth cannot eliminate the increased gap. When the material is broken, the gap that cannot be eliminated will put the crown and bolt in an unfavorable stress state, which will shorten the life of the crown and ring seat, and the tooth is often broken. Although the structure of the crown has been improved on the basis of the crushing teeth tightening method, the gate structure of the crown has been changed to a groove shape, which is not easy to break teeth, but the strength and stiffness are greater. The connection between the tooth crown and the tooth ring seat is also the pretightening force of the fastening bolt acting on a part of the tooth crown with greater strength and stiffness. The crown is still easy to loosen, resulting in wear of the connecting part and reducing the service life of the crown and ring seat.
2 Improvement measures for crushing teeth sudden reinforcement For crushing roll teeth broken, crushing roll teeth and tooth base joint surface sticking material problems, the following measures can be adopted. The first is to improve the fastening mode of the crushing tooth structure to improve its stress state and increase the service life of the crushing roll tooth; Second, the crushing roller teeth should be inspected to reduce casting defects as much as possible. The improved fastening method of the crushing teeth is shown in the schematic diagram. A bolt is only used to fasten the crown of the tooth and the matching surface of the tooth ring seat on both sides of the tooth tip to the unilateral surface B, and the pretightening force of the bolt acts on the two fastened parts at the same time. The positive pressure generated by bolt fastening fully acts on the matching surface B of the tooth ring seat and the tooth crown, and then generates a friction force on the B side that is sufficient to overcome the radial component of the tooth crown when broken to completely tighten the two into one, and the tooth ring seat and the tooth crown will not move along the matching surface B to prevent the relative slip of the tooth crown. After tightening, the matching gap between the two surfaces exists only on the one-sided surface C of the rotating circumference of the tooth tip which has no effect on the crushing. The surfaces A and D which are in contact with each other and are easy to process bear the radial inward impact of the tooth crown, and the closely contacted surface B bears the positive impact of the circumference of the tooth crown. The above analysis shows that the fastening mode and stress state of the improved crushing tooth structure are superior to the traditional structure.
This solution has been applied in mineral sizers, a sieve type double-toothed roller developed by our company, which is in normal operation at the Beskuduk coal mine in Xinjiang. Compared with the prior art, the mineral sizers of this tooth structure have the advantages of reasonable and reliable fastening of the crushing teeth, good force state of the teeth, strong structure, easy processing of the surface to be processed, convenient installation and replacement, etc., which will be widely used in the mineral sizers industry.