Causes Of Damage To Blades Of Twin-shaft Mixer And Its Improvement

Cement plants generally use twin-shaft mixers for pre-wetting and mixing. After the raw material powder is pre-wetted and mixed, the balling effect is greatly improved. Twin-shaft mixers used in cement plants generally have problems such as heavy load, uneven load, easy bending and breaking of the shaft, easy ash in the bearing, etc., with high failure rate, high maintenance cost, high power consumption, and difficult maintenance. This article analyzes the common faults that occur in the use of twin-shaft mixers and proposes solutions.
The head and tail shafts of the twin-shaft mixer are inserted into the pipe shaft and fixed by pins. The shaft and hole generally adopt transition fit. This kind of assembly and disassembly is very difficult. In order to facilitate maintenance, some manufacturers use clearance fit for the shaft and hole. In this way, the head, tail shaft and pipe shaft will produce relative rotation, resulting in wear of the head, tail shaft and pipe shaft, resulting in the whole rotor being non-concentric, and the clearance fit load mainly acts on the pin, which is easy to be sheared off. The pin breaks in the shaft hole and is difficult to remove, and it is very difficult to replace the pin.
Some manufacturers weld the mixing blades directly to the pipe shaft during design. The blades need to be replaced frequently during use. When replacing, they must be cut with acetylene flame or welded with electric welding. The pipe shaft is greatly affected by heat and is easily deformed.
The bearing chamber of the twin-shaft mixer is sealed by felt or packing. When the sealing element is worn, dust directly enters the bearing chamber, causing the bearing to burn. Solution to the structure of the twin-shaft mixer
Reform the unreasonable structure of the twin-shaft mixer
The head and tail shafts and the pipe shaft are connected with a connecting plate (the outer diameter of the connecting plate must be smaller than the diameter of the wallboard bearing seat hole). The ash discharge hole is cast on the bearing seat. If the sealing element is worn, the material is discharged from the ash discharge hole and cannot enter the bearing chamber.
In modern industrial production, mixing and stirring are crucial to product quality control. In order to meet the needs of this key link, it is particularly important to choose a mixing equipment with stable performance.
The blades of the twin-shaft mixer are the main components of the twin-shaft mixer. When the blades are worn, the uniformity and efficiency of the mixer will be significantly reduced. Therefore, damage analysis and improvement of the blades will help improve wear resistance and extend the service life of the blades. When working, the mixer blades not only have a stirring effect, but also have a certain thrust effect to push the material forward for transportation.
The reasons for blade damage and failure are as follows: 1. The blade is broken at the connection with the shaft 2. The blade shaft is bent and deformed 3. The working surface and top arc surface of the blade are worn 4. The amount of material pushed by the blade is too large, causing the mixer to overload. The above two types of blade damage and failure are mainly caused by improper manufacturing and use of the blades. Therefore, improvements in the performance, material and processing methods of the blade shaft can avoid the occurrence of these problems. Blade wear is the main cause of blade damage. The blade is installed on the mixer shaft. After working for a period of time, under the continuous friction and extrusion of the material, the top of the blade will gradually become thinner during the rotation process, and the wear at the two corners of the fan-shaped working surface will be more serious. When the blade rotation diameter and blade thickness are worn to a certain extent, the output of the conveyed material will be significantly reduced.