Will the Rotary Kiln Shell Break, and What is Going on if It Breaks?

时间:2021-02-26 作者 :超级管理员

Rotary kiln shell fracture is a very rare situation. After the rotary kiln shell fractures, samples of the fractured part should be sent to professional institutions or manufacturers for further quantitative analysis of the cause of the shell fracture accident, including fracture analysis, material chemical composition analysis, Mechanical performance test, hardness test, etc. Why does the rotary kiln shell break?

Rotary kiln

   The cylinder body of the rotary kiln under the tyre has different degrees of necking, and continuous operation will easily cause the cylinder body to break. The cylinder at the junction of the cooling machine and the discharge port of the rotary kiln is prone to cylinder fracture accidents.


   Rotary kiln shell fracture usually has cracks distributed along the circumference of the section of the shell, accompanied by the phenomenon of shell bending. Once the crack exceeds more than 1/3 of the circumference of the kiln, a cylinder fracture accident may occur.


The overall strength is low. A number of multi-tube cooler discharge holes are evenly distributed on the circumference of the cylinder at the junction of the cooling cylinder and the kiln discharge port, so that the actual iron plate length is only about 1/2 of the circumference, and the overall strength is significantly reduced , So it is very easy to break here.


   Grooves were formed in the process of manufacturing, transportation and installation of the rotary kiln shell, resulting in micro cracks. After the cracks appear, rush repairs must be carried out. However, during the emergency repair process, if the welder's welding technique is not good enough, or the welding filler metal is not properly selected, the welded part is likely to crack again and extend and expand, resulting in the occurrence of a cylinder fracture accident.


  Material fatigue under high temperature conditions, the cylinder body has to bear the action of alternating load and cold and heat changes for a long time. When the kiln is stopped due to production reasons and non-production reasons, it may cause radial deformation of the section of the cylinder body. The thermal calibration of the rotary kiln shows that the surface temperature of the cylinder is often as high as 300℃. In this high temperature working environment, especially the alternating cold and heat, it is easy to cause the steel plate of the rotary kiln to fatigue, decrease the rigidity, and then break.


If there are crack defects in the kiln shell fracture source area before the fracture, after repair welding but the welding quality is poor, the initial crack cracks longitudinally along both sides of the repair welding place, extends to both ends for a certain length and then bifurcates, gradually under the action of gravity Turn to the ring to expand until the cylinder breaks and falls off the kiln base.


The kiln shell belongs to the low-temperature brittle fracture generated on the basis of large-scale defects. Under the condition of low material temperature, dynamic load directly leads to rapid brittle fracture. Before the final low-temperature fracture occurs, the defect has experienced corrosion damage and thermal welding damage. And crack fatigue and other growth processes.

   Generally speaking, rotary kiln shell fracture is relatively rare, but it is not without such phenomena. In most cases, it is caused by some small manufacturers or irresponsible factories cutting corners or low manufacturing level in the processing process. Therefore, it is recommended that you choose a professional large factory such as Hongke Heavy Industry for customized production when buying a rotary kiln. In order to provide you with high-quality equipment.