What Are The Reasons For The Damage Of Refractory Bricks

The diameter of the new dry-process cement rotary kiln shell has been increasing with the expansion of production capacity, from 3300mm to today's 6400mm, almost doubled. At present, there are two main types of refractory bricks used in cement rotary kilns. Among them, the basic refractory bricks generally adopt the VDZ series brick type (international general series, the width of the middle is constant at 71.5mm), and the sintered silico-alumina refractory bricks generally adopt the ISO series brick type. (International general series, the width of the big head is constant at 103mm).

The height and thickness of the refractory bricks are relatively fixed, and there is not much room for adjustment. If the height of the refractory brick is too low, the heat insulation performance of the refractory brick is too poor, the hot end of the brick is slightly damaged, the temperature of the kiln body will rise above the upper limit, and the kiln will be stopped and replaced: if the height of the refractory brick is too high, the quality of the brick It will increase, it will cause excessive deformation of the kiln body, and damage the refractory bricks.

The increase of the kiln diameter, the increase of the speed, especially the second gear of the technology, the speed should be higher, reaching 5r/min, which will easily cause the ovality of the cylinder to increase, correspondingly higher requirements on the compressive stress of refractory bricks, so it is required The compressive strength of refractory bricks should be high. Especially for the cylinder of the tyre, it is required that the refractory bricks near the tyre should be made of refractory bricks with the same characteristics.

With the expansion of the kiln diameter, the corresponding center angle a of the refractory bricks will appear, and the stress on the refractory bricks will increase. At the same time, more stringent requirements are put forward on the dimensional tolerances of the refractory bricks. The body diameter reaches 6.4m, and the external dimensions of the refractory bricks in the kiln are extremely demanded. The refractory bricks with large deviations in the external dimensions are caused by accidents such as bricks falling off during the construction and use, which seriously endangers the normal operation of the cement kiln.