Don't Let the Rotor "Drag": The Core Code for the Efficient Operation of Hydrapulpers
The rotor is the core part of the hydrapulper. The Fuchs rotor is commonly used in low - consistency pulpers, and the performance of the rotor directly affects the output of the hydrapulper and the quality of the pulp. The rotor of the pulper is like a "knife". After being used for a period of time, it will be blunted. The pulping effect of the pulper will gradually decline, the power consumption will rise, and the pulping effect will deteriorate, which indicates that the "knife" of the pulper needs to be "sharpened".
The vertical ribs of the rotor and the front blades of the wing plates are worn. After the rotor has been used for a while, the current drops (below 60 - 70% of the rated current), and the output decreases accordingly. This shows that the rotor is worn. The wear - resistant materials surfacing - welded on the front surface of the wing plate blades and the front of the vertical ribs, after being used for two to three months, many edges and corners are blunted. The pulping ability of the rotor is reduced, the turbulence is decreased, resulting in a decrease in the output of the pulper and a decline in the quality of the pulp. According to our tests, after replacing the rotor, the current of the pulper increases by about 18 - 20%, and the consistency increases by about 15 - 25%.
(Comparison of Current Curves Before and After Rotor Replacement)
The bottom of the rotor and the bottom knife are worn. There is generally a clearance requirement of 0.5 - 1.5mm between the bottom knife of the rotor and the bottom knife of the screen plate. When this clearance is ensured, the pulping ability is optimal. If the clearance is too large, pulp will be blocked at the bottom of the rotor and the screen plate, accelerating the wear rate of the rotor and the screen plate, increasing power consumption, and making the equipment difficult to start. If the rotor is used for more than half a year, it will inevitably cause serious damage to the rotor body. The original size and geometric angles cannot be guaranteed, which will cause difficulties in subsequent repairs. Many rotors even have no repair value in the end. (In the photo, the bottom plane of the 60m³ pulper rotor is worn about 20mm.)
The front angle and negative angle of the rotor are worn. Each wing plate of the rotor has a front angle and a secondary angle. The size of the angles should vary according to the different specifications of the rotor. An appropriate secondary angle can enhance the cleaning ability of the screen plate. When the bottom surface of the rotor is worn, the entire secondary angle changes, and the cleaning ability of the screen plate decreases.
The balance of the rotor. After the rotor is repaired, it needs to be re - balanced. Some manufacturers do not have special equipment and tools, so they either do not balance the rotor or the balance is not up to standard, resulting in excessive unbalance. After installation and use, the operation will be unstable, the current will fluctuate greatly, and it will cause great damage to the transmission parts, bearings, and reducers.
The maintenance of the rotor is highly professional. Many paper mills, in order to save costs or time, arrange in - factory maintenance workers to repair the rotor after it is removed from the machine or find some non - professional factories for repair. The angles, dimensions, and materials of the rotor are difficult to guarantee. In addition, according to the different materials of the rotor body, the selection of maintenance welding materials and the size of the welding current directly affect the repair effect of the rotor. After repair, the rotor is not up to standard at all, so many paper mills have made a lot of unproductive efforts in the maintenance of the pulper.
If the rotor is used and maintained correctly, its service life can reach more than 15 years. Therefore, paper mills should attach great importance to the maintenance of the rotor. Firstly, a complete maintenance system should be established. During daily operation, closely monitor various operating parameters of the pulper, such as current, output, and pulp quality. Once abnormalities are found, stop the machine in time to check the wear condition of the rotor. Regularly conduct comprehensive inspections and maintenance on the rotor, including the repair of worn parts and balance verification. Secondly, choose professional maintenance teams or qualified manufacturers for repair, ensure the use of appropriate maintenance processes and materials, and strictly follow the standards for operation. Only in this way can the service life of the rotor be effectively extended, the efficient and stable operation of the pulper be guaranteed, production costs be reduced, and the economic benefits and market competitiveness of paper mills be improved. In the current context of rapid equipment upgrading, reasonable maintenance of key equipment components to maximize their performance is undoubtedly an important part of the sustainable development of enterprises.
(Photos of the Fox Rotor Before and After Repair)
