The synchronous protection device of Mineral sizer
Introduction
Mineral sizer, as a device that can crush materials ranging from 300mm to 2000mm to the specified particle size, has the functions of screening, selective crushing and reducing the crushing volume during the crushing process. It is widely used in industries such as mining, chemical engineering and power. The toothed roller is the main working component of the Mineral sizer. The relative position of the tooth profiles of the two toothed rollers has an impact on the crushing effect. Under the same diameter of toothed rollers, the material that can be bitten cannot reach the maximum. When driven by a single motor, the two toothed rollers can ensure synchronous speeds but cannot work with a single roller. The Mineral sizer driven by two motors cannot ensure synchronous speeds of the toothed rollers.
In response to the technical issues mentioned above, a synchronous protection device for Mineral sizer is developed, which enables the Mineral sizer to synchronize its rotational speed. Under the condition of the same diameter of the toothed roller, the relative position of the tooth profile can maximize the amount of material bitten, thereby protecting the toothed roller.
Synchronous protection device
The synchronous protection device of Mineral sizer includes shaft sleeves connected to the gear roller shaft one and gear roller shaft two, as well as several conical sleeves on the shaft sleeves. Each conical surface of the conical sleeve is meshed with force-transmitting steel balls. The shaft sleeve and the gear transmit torque through a pin shaft with a compression spring in several torque-limiting components set on the gear. There is a bearing between the gear and the shaft sleeve, and the cover seals the bearing. There are several torque-limiting components on the gear, and the gear can be a friction wheel. When subjected to a certain torque, the pin shaft with a compression spring in the torque-limiting component moves, and the force-transmitting steel ball detaches from the cone sleeve.
The advantages of synchronous protection devices
The Mineral sizer with synchronous gears has two toothed rollers rotating at the same speed during operation, which determines the fixed relative position of the tooth profile and ensures the bite Angle of the feed. When the same feed particle size is crushed, the diameter of the toothed rollers is reduced, reducing costs. The pre-compression spring in the torque-limiting component provides a preset torque to the inclined surface on the pin shaft acting on the force transmission steel ball. When an unbreakable object enters, the pin shaft in the torque-limiting component moves away, the force-transmitting steel ball detaches from the cone sleeve, and the shaft sleeve and gear rotate freely, that is, the two toothed rollers separate, and the toothed rollers rotate or stop independently to protect the toothed rollers.
The reasons for installing synchronous protection devices
Prevent mechanical interference and damage
During the operation of the mineral sizer, if the two toothed rollers do not rotate synchronously, the teeth of the two toothed rollers may directly collide and squeeze, causing the teeth to crack or break. The gear roller shaft is subjected to additional radial force, causing the bearing to overheat and crack. It may even cause structural damage such as rack deformation, significantly increasing maintenance costs and downtime.
Avoid damage caused by overloading
During the Mineral crushing process of Mineral sizer, the material properties are complex. If super-hard impurities are mixed in or the instantaneous feeding amount is too large, it may cause the torque borne by the toothed roller to far exceed the design range. Without a synchronous protection device, the motor may burn out due to overload, and components such as transmission gears and reducers may experience tooth surface adhesion and shaft system breakage due to overloading. If the toothed roller is subjected to non-uniform impact for a long time, it will accelerate fatigue wear and shorten its service life.
Common Faults and Solutions of Synchronous Devices
Abnormal gear meshing
The main manifestations are abnormal noise and intensified vibration during gear transmission, and may also be accompanied by uneven wear on the tooth surface and pitting corrosion. The occurrence of faults often stems from insufficient gear installation accuracy of mineral sizer and improper adjustment of axial and radial clearances, which leads to the failure of gears to mesh correctly during operation. Or there may be manufacturing defects in the gears themselves, such as tooth profile errors, cumulative pitch errors, etc., which affect the smoothness of gear transmission.
Solution: Readjust the gear installation clearance to ensure the accurate axial and radial positions of the gears. Replace gears with manufacturing defects; Strengthen the lubrication management of gears, change the lubricating oil regularly, and reduce the wear of tooth surfaces.
The torque-limiting component failed
The main manifestations are that the pin shaft cannot move normally, and the force-transmitting steel balls cannot be separated from the cone sleeve in time. As a result, when encountering unbreakable objects entering, the two toothed rollers cannot be separated in time, and the toothed rollers continuously bear excessive torque, causing damage to the toothed rollers or related transmission components. The occurrence of the fault might be due to the decline in the performance of the compression spring in the torque-limiting component, with insufficient elastic force, which is unable to drive the pin shaft to move. Or there may be jamming between the pin shaft and the relevant channels, such as impurities entering or surface rust, which affects the normal sliding of the pin shaft. It could also be that the surface of the force-transmitting steel ball is worn out, and the fit relationship between it and the cone sleeve changes, making it impossible to disengage smoothly.
Solution: Conduct performance tests on the compression spring. If the elasticity is insufficient, replace it with a new one. Inspect the pin shafts and channels, remove impurities from them, carry out rust removal treatment on the rusted parts and apply lubricating oil. Replace the worn force transmission steel balls to ensure that the fit between them and the cone sleeve meets the design requirements.
Summary
The addition of a synchronous protection device to Mineral sizer can enhance the stability and reliability of the equipment’s operation. The synchronous protection device can respond promptly when the torque-limiting component malfunctions, preventing the further expansion of the fault.
