After the new dry process cement rotary kiln is put into operation, the problem of heating of the supporting roller tiles will occur. In serious cases, it will lead to accidents such as tile burning, tile collapse, supporting roller shaft wear, etc., thus affecting the stable operation of the rotary kiln. Therefore, it is very important to correctly install and adjust the supporting roller tiles, and to strengthen the inspection and monitoring of the supporting roller during operation.
Learn more about the design features of supporting wheels and tiles
Due to differences in technology, the designs of supporting rollers and tiles of various types of rotary kilns are different. Generally speaking, the new dry production line technology of various design departments has matured, and the processing of supporting wheels and tiles can also meet the design requirements. During on-site installation, the contact angle of the tiles and the inlet and outlet oil wedge can also be basically achieved. specification. However, if we carefully study and analyze the design of various types of rotary kiln supporting rollers and tiles, we can find that due to the unique design and technical differences of various cement design institutes, the designs of supporting wheels and tiles are also different, and their thrust plates The position is also quite different. In some rotary kilns, the thrust plate of the supporting roller is on the outside of the supporting roller shaft, while in some cases the supporting roller shaft is on the side of the supporting roller. When the rotary kiln is running, if the monitoring is not in place when the working conditions fluctuate and the supporting roller tiles heat up, the maintenance personnel should first understand the difference in the position of the thrust surface of the supporting roller tiles, and change the thrust by adjusting the relative position between the tiles and the thrust plate. The gap between the plate and the tile is eliminated, thus eliminating the friction and heating between the two.
Details that cannot be ignored during installation
The contact between the supporting roller tiles of the rotary kiln should be controlled at about 30°, and the oil wedge at the inlet and outlet should meet the requirements. During installation, the relevant dimensions of the supporting roller shaft and tiles must be reviewed, and the casting quality of the supporting roller tiles and spherical tile seats must be confirmed.
Details that are often overlooked during the actual installation process are: the scraping and grinding of the inlet and outlet oil wedges does not meet the requirements; the size and machining accuracy of the support wheel shaft are not checked; the tile pressure plate bolts, oil spoon fixing bolts, and oil drip pan fixing bolts are not tightened and tightened according to standards. Anti-loosening treatment; the relative dimensions of the oil scoop and the roller seat in the roller seat have not been rechecked, etc., thus leaving great hidden dangers to the operation of the roller tile. If the bolts are loose, it is easy to pull the tile over; friction between the oil spoon and the internal parts of the roller seat will cause damage to the oil spoon, insufficient oil supply, and the oil spoon will get stuck inside the roller seat, causing the tile to be scrapped. During installation, foreign objects must not fall between the oil spoon, tile surface and shaft.
The correct installation method is: before installation, measure the size of the supporting roller journal to detect the journal size error and roundness; check whether the shaft surface has been grinded, whether the supporting roller tile is deformed, whether the spherical tile is leaking, and whether the spherical tile is leaking. The contact angle of the tile should be controlled at about 30° during grinding; the oil wedge in and out should be controlled reasonably; the oil spoon fixing bolts, the oil dripping plate fixing bolts, the tile and the pressure block bolts should all be checked to see if they are fixed in place and anti-loosened; the supporting roller The relative size of the oil spoon in the seat and the roller seat also needs to be measured by disassembling the end cover of the roller seat to see if there is friction, and adjusting the gasket to adjust the gap.
Carefully arrange preparations before adjustment
After the new supporting rollerl tile is installed and repaired, due to the possible imbalance between the supporting roller and the kiln roller belt, and the unreasonable size of the center of the supporting wheel and the wheel belt, it may cause the end surface of the tile and the contact area between the tile surface and the shaft to heat up, so it is necessary to Adjustment.
Before adjustment, debugging personnel must carefully make relevant preparations, such as understanding the design, installation, protection, etc., and preparing corresponding tools and solutions. After understanding the basic design of the kiln, it is necessary to verify the installation process and hidden data, such as the centerline error, the scraping of the supporting roller tiles, whether the connecting parts in the supporting roller seat are reliable, whether the oil quality is reasonable, Check whether there are any foreign objects in the roller seat. In terms of temperature protection, rotary kilns are usually equipped with tile and oil temperature measuring devices. The setting value should generally be set to alarm when it is greater than 45 degrees Celsius, and to trip when it is greater than 55 degrees Celsius. The main tools commonly used in the adjustment process include a thin jack of about 75 tons, a hand-held thermometer, a dial indicator, homemade special wrenches for loosening anchor bolts and tightening bolts, spare lubricating oil, and a refueling can.
When the rotary kiln starts to rotate slowly, it is necessary to carefully observe the actual oil temperature and shaft temperature change trends on site. If the temperature displayed by the central control tile temperature measuring device is different from the actual temperature, it should be observed on site. When there is a temperature change, special attention should be paid to the location where the heat source comes from and the upward trend.
Adjustment method for supporting roller tile heating
In addition to major defects in the manufacturing and installation of the support roller shaft and tiles, unreasonable oil wedges at the tile openings, and foreign matter entering the tile openings that seriously damage the oil model and require the tiles to be scraped and ground, other serious faults can usually be solved by adjusting the movement of the support roller seat. To eliminate the problem of heating of supporting roller tiles.
When the central control room reports that the tile temperature or the oil pool temperature exceeds 45 degrees Celsius, maintenance personnel are required to go to the site to determine the specific heating location and confirm whether the end surface or the tile surface is heated. Please pay attention to the following methods when operating:
Direction control during adjustment: Use the spiral law of both hands to guide the adjustment of the supporting roller base on site. The method is simple and practical, that is, hold the middle finger, ring finger, and little finger of the left and right hands tightly facing the supporting roller. The direction is consistent with the rotation direction of the supporting roller. The index finger and Keep your thumb straight, the thumb direction is the moving direction of the supporting roller (axial direction of the rotary kiln), and the direction of the index finger is the moving direction of the supporting roller (radial direction of the rotary kiln).
Adjustment method when the thrust surface is heated: When the thrust surface of a supporting roller seat tile is heated, the gap between the thrust plate and the tile can be eliminated by advancing (retreating) the supporting roller seat to move the supporting roller along the direction of the kiln center line to eliminate frictional heating. In order to ensure that the center line remains unchanged, after adjusting the supporting wheel seat, adjust the supporting wheel seat diagonally opposite to the supporting roller seat.
Adjustment method when the tile surface is hot: When the tile surface of the supporting roller seat is heated, the supporting roller seat can be withdrawn to move the supporting roller in the vertical direction along the kiln center line to relieve the stress on the tile and eliminate the heat.
Adjustment method when the thrust surface and tile surface are heated at the same time: When the thrust surface of a supporting roller seat tile is heated, the gap between the thrust plate and the tile can be changed to eliminate friction by advancing (retreating) the supporting wheel seat to move the supporting wheel along the kiln center line. To ensure that the center line remains unchanged, after adjusting the roller seat, adjust the roller seat diagonally opposite to the roller seat.
Control of the kiln speed during adjustment: The kiln can be stopped for a short time during adjustment, but the kiln can also be adjusted during normal operation. At this time, the kiln speed should be appropriately reduced, generally around 1r/m is more suitable, especially when using When the jack pushes the kiln inwards, it is more necessary to rotate the kiln slowly or control the kiln speed at 1rp/m.
Control of the displacement of the roller seat during adjustment: Sometimes the axial stop of the roller seat must be removed during adjustment. In order to ensure the accuracy of the adjustment, two dial indicators should be used for each roller seat during the adjustment process. The amount is between 0.2mm~0.35mm.
Safety control during adjustment: Because the anchor bolts need to be loosened during adjustment, the kiln may still be running at this time, so a jack should be used to hold the kiln up instead of the load when the anchor bolts are loose. Since there are many people during adjustment, constant observation is required. The internal conditions of the roller seat, do not drop foreign objects into the roller seat at this time. When inspecting before adjustment, during adjustment, and after adjustment, when touching the surface of the roller seat with your hands, you should pay attention to personal safety injuries caused by the movement of the oil spoon.
Observation and monitoring after adjustment: After adjustment, pay attention to observe whether the gap between the thrust plate and the tiles changes; whether there are any abnormal changes in the temperature of other supporting rollers in the same gear of the same set of supporting rollers and the other two supporting roller tiles; Whether the temperature of each tile temperature is adjusted appropriately.
Monitoring during normal operation fluctuations: During the operation of the supporting wheel tile, pay close attention to the changes in the supporting roller shaft end face, shaft surface, and oil temperature, whether the working pressure of the hydraulic gear wheel is appropriate, and whether the supporting roller moves up and down normally.
