The scraping and installation methods of the thrust bearing of the cone crusher

Scraping and installation methods of thrust bearings for cone crushers:

I. Function and Structure of the Thrust Bearing: The function of the thrust bearing in the cone crusher is to support the empty eccentric shaft and reduce the running resistance of the empty eccentric shaft. Meanwhile, the installation accuracy directly affects the meshing clearance of the bevel gear. Ensuring a reasonable fit clearance between the empty eccentric shaft sleeve and the main shaft can prevent the occurrence of "runaway" phenomena.

2. Scraping of the thrust bearing During the operation of the crusher, the upper circular plate of the thrust bearing is connected to the empty eccentric shaft 1 with pins and rotates along with it. The three-pronged circular plate 5 below is inlaid with the bottom cover 7 through the three prongs around it. The middle circular plate 3 and the central circular plate slide relatively. Then, a total of three contact surfaces, namely between the pieces, between piece 3 and piece 4, and between piece 4 and piece 5, need to be scraped to ensure their good operating condition. The purpose of scraping is to ensure uniform pressure on the flat bearing and create conditions for good liquid lubrication. The entire process can be divided into two parts: rough scraping and fine scraping. When scraping, you can first check the flatness of the two contact surfaces. You can apply red lead powder evenly and thinly for testing. First, rotate the two contact surfaces in a clockwise direction. For the second scraping, rotate them in a counterclockwise direction. Then, rub them alternately. Then start the rough scraping. When scraping, you can use a 25mm flat-mouthed special scraper or a slightly larger diameter is also acceptable. When performing rough scraping, all the contact surfaces after grinding should be scraped off. Areas that have not been touched should not be scraped. The movement distance of the knife mark should not exceed 25mm, and the scraping knife mark should be in a hook shape. Repeat the grinding process and then scrape it off. Each time you scrape, you can retain some contact points. When the two contact points are basically evenly distributed, the oil accumulation points can be precisely scraped by the monthly scraper. At this time, it should be noted that starting from the center of the circular plate, the larger the diameter, the better the distribution points of the contact points should be. After repeated grinding and precise scraping, ensure that there are no less than 3 contact points within every 25mm X 25mm between the two contact surfaces. The scraping of the three contact surfaces can all be done in the same way as mentioned above. Considering the different materials of each round plate, a harder round plate can be selected for scraping first, and this can be used as the reference surface. Uneven contact points or too many or too few contact points on the contact surface will all affect the flat operating state of the plain bearing. During on-site fault maintenance, it was repeatedly found that the movement speed of the three-jaw circular plate was not zero, forcibly damaging the circumferential three jaws on the three-jaw circular plate, accelerating the wear of the circular plate (friction plate) in the circumferential direction. After wear, it changed from a circular shape to an irregular elliptical one, causing the crusher to malfunction or resulting in a "flying wheel" phenomenon.

Iii. Installation of Thrust Bearings Ensuring the installation accuracy of thrust bearings on the cone crusher is a necessary condition for the normal operation of the crusher. Installation can be carried out in the following steps:

(1) The installation of the young thrust bearing should be consistent with the sequence of the contact surfaces between them during the scraping process.

(2) First, when placing the three-jaw circular plate on the bottom cover, it should be stable. If there are any casting burrs or remaining molding sand inside the bottom cover, they should be cleaned up thoroughly. Then, pour in lubricating oil until it is exactly flush with the upper plane of the three-jaw circular plate to check if it is stable. The inspection can be carried out by gently tapping around the three-jaw disc with a lifting tool. If oil splashes out from the circumference of the disc, it indicates that there is still a gap between the three-jaw disc and the bottom cover, and it should be cleaned and repaired again.

(3) Then install the medium round plate and the round plate in sequence. The detection method can still be the same as mentioned above.

(4) Finally, install the empty eccentric shaft, spherical bearing frame and main shaft. When hoisting the empty eccentric shaft, the counterweight of the large gear should be placed above the small bevel gear to align the outer ends of the bevel gears. After the spherical bearing is installed, the spherical bearing housing and the machine base should adopt an interference fit as much as possible, and it is better to be tight rather than loose. During this period, three data were measured successively: the gap a of the conical bevel tooth; The clearance b between the main shaft and the cone sleeve; The clearance c between the end face of the empty eccentric shaft and the bottom of the spherical bearing frame.

(5) Based on the above three data points, the gap plate for installing the tapered stop bearing is uniformly considered, that is, the position between the three-jaw disc and the machine bottom cover is determined. The gap plate is made of ordinary plates, but it is advisable to avoid using the superposition of steel plate thicknesses as much as possible to complete it. If the gap is greater than 3.5mm, it is necessary to consider reducing the thickness of the gasket at the connection between the machine bottom cover and the frame or directly lowering the total height of the bottom cover itself, based on on-site experience.