What should be paid attention to when replacing silicon carbide roller

1. It is best to replace the silicon carbide roller when stopping the kiln or low temperature (below 800 degrees), so as to ensure safety and long service life of the replacement roller. The roller bar can not be broken in one place more than two, otherwise, it must be replaced urgently, or even stop the kiln immediately.

2. In the actual operation process, often for a variety of reasons we can not immediately reduce the firing or stop the kiln to replace the roller, but while normal firing, while replacing the broken roller. At this time, we should first take out the new roller (with the same model as the broken roller), plug one end of the new roller with fire-resistant cotton, the other end is loaded with spring; Then take out a roller in the 400-500 degree area, and change the new roller to preheat for 20-30 minutes (one end of the plug refractory cotton has been inserted into the transmission side), or install the high temperature area type roller in the 400-500 degree area in advance for replacement.

3. The length of refractory cotton needed to plug the new roller is L, that is, the thickness of kiln wall; The initial depth of cotton plug is L+L1, that is, the part of porcelain tube exposed to kiln wall plus the thickness of kiln wall; The end depth of cotton plug is L1, that is, the part of porcelain tube exposed to kiln wall. The fire-resistant cotton at one end of the new porcelain tube should be plugged first, and the fire-resistant cotton at the other end should be plugged after being installed. (as shown below) L L L1 Refractory cotton L1 kiln wall thickness L

4. The broken silicon carbide roller is taken out, and the brick hole is temporarily plugged with refractory cotton to avoid heat spillover and cold air entering; The porcelain tube on the side of the transmission shall be removed by removing the transmission gear or pushed into the kiln (note that the broken roller shall fall below the horizontal plane of the roller and shall not hinder the operation of the kiln plate), and shall be cleaned after the kiln is stopped. Special attention should be paid to the process of taking out the roller to prevent the roller from being burned due to sudden cold fracture.

5. Take out the preheated new roller, and slowly insert one end of the plugged refractory cotton into the broken roller while rotating. Be sure not to insert the speed too fast, and keep rotating at the same time.

6. For roller kiln wall plug out of the drive side don't mount drive gear, use refractory cotton first porcelain tube gap between simple plug plug, and continue to kept turning porcelain tube, wait for transmission of porcelain tube head on one side of the cooled to a certain temperature before installation drive gear, and porcelain tube gently into steel bushing, so as to avoid the thermal contact porcelain tube steel bushing damaged due to rapid cooling. Note that the drive gears must be aligned, level and at the same distance from the adjacent front and rear drive gears.

7. After the installation of the new roller, plug the gap between the two ends of the roller and the kiln wall with refractory cotton, especially the gap between the lower part of the porcelain tube and the kiln wall with refractory cotton plug. At the same time, the end of the roller is not blocked refractory cotton with cotton stopper, the depth of cotton stopper according to the requirements of Point 3. Finally, check whether the spring falls on the bearing, and write the date and time of replacement, model and serial number of the porcelain tube on one end of the porcelain tube with a marker pen.

8. Record the date, time, model and quantity of the broken roller, the sequence number of the broken roller, the date and time of the previous replacement of the broken roller and the person in charge on duty in the special Record book of the broken roller. Note: the continuous fracture caused by replacing the porcelain tube should also be recorded in detail.

9. Take out the broken roller to observe (roller type, fracture position, wear, thickness, density, other abnormalities), analyze, discuss, and report to the superior, so as to take effective control and improvement measures.