The practical installation method of SKF combined bearing is worth seeing
The rolling bearing is composed of the above two bearing structures in a set of bearings. Skf Combined Bearing Such as needle roller and thrust cylindrical roller combined bearing, needle roller and thrust ball combined bearing, needle roller and angular contact ball combined bearing, etc. SKF combined bearings, such as SKF nkia5902, SKF nkia5906 and SKF nkx15, have various combinations. Next, let’s take a look at their installation methods.
1. Install bearings in a clean condition: Skf Combined Bearing the installation site shall be separated from lathes, grinders and other mechanical equipment. The site shall be cleaned, often dry and clean, and beware of iron filings, sand, dust and moisture entering the bearing. Check the bearing housing (seat), shaft and other relevant components of the bearing to ensure that they are clean. The bearing should remain in the original packaging until the moment before the device to avoid contamination.
2. Check the bearing model and prepare the equipment: Skf Combined Bearing check whether the bearing model and size meet the requirements of the device, select the appropriate assembly method according to the structural characteristics of the bearing and the common parts, and prepare the equipment and measuring tools.
The commonly used Skf Combined Bearing devices include hand hammer, copper rod, sleeve, special backing plate, screw mosquito fixture, press, etc., and the measuring tools include vernier caliper, micrometer, dial indicator, etc.
3. Check the size and Skf Combined Bearing shape of all components in contact with the bearing: the diameter of cylindrical journal, and measure four points of each three planes with a micrometer. For the bore diameter of bearing housing (seat), use internal gauge to measure four points on three planes.
4. Clearing and trimming Skf Combined Bearing the assembly appearance of common parts with SKF Bearing: before the device, the appearance of journal, bearing seat shell hole, shoulder end face, and the common appearance of connecting parts such as bushing, washer and end cover shall be carefully inspected.
If there are bruises, Skf Combined Bearing rust layer, wear debris, sand, dust and soil, the bearing device is difficult and the assembly position is inaccurate; Second, these attachments constitute abrasives, which are easy to rub the surface of the bearing task and affect the assembly quality. It can be trimmed with fine file and fine emery cloth. Pay attention not to lose the accuracy together. Clean the attachments on the assembly surface with cotton yarn.
5. Open the bearing package and Skf Combined Bearing wipe off the rust inhibitor on the inner hole and outer surface of the bearing.
6. If the bearing is Skf Combined Bearing smooth with grease and used at extremely high or low temperature, or the grease is incompatible with rust inhibitor, carefully clean and dry the bearing.
7. Generally, the tighter common surface shall be assembled first.
8. The shaft is interference common: use mineral oil to fine smooth the inner hole of the bearing. When installing the bearing device, ensure that the rear of the bearing device is perpendicular to the shaft (Fig. 5), and apply appropriate sleeve force on the inner ring.
9. The bearing housing (seat) is interference common: use mineral oil to smooth the outer surface of the bearing. When installing the bearing, ensure that the rear of the bearing device is perpendicular to the bearing housing (seat), and apply appropriate sleeve force on the outer ring.
10. The shaft and bearing box (seat) are also installed: smooth the inner hole and outer surface of the bearing with mineral oil. Ensure that the shaft and bearing box (seat) are adjusted so that the rear of the bearing device is perpendicular to the shaft. When installing the device, use a suitable sleeve to force the inner ring of the table.
11. After the SKF Bearing device is in the correct position, install the locking installation.
12. Make sure that the bearing inner ring (or shaft), bearing outer ring (or wheel, etc.) can change sensitively.
13. If the bearing is smooth with oil, pay attention to the use of accurate smooth oil and dosage. If the bearing is smooth with grease, add smooth grease at this time. If the bearing must also be installed into the shaft and bearing housing (seat), it is necessary to add smooth grease earlier.
Under normal conditions, the bearing should be completely filled with smooth grease (except for high-speed). In addition, the remaining space (about 30-50%) in the bearing housing (seat) should be filled with smooth grease.
14. When the bearing is hot loaded, the bearing heater or oil bath shall be used for heating, and the temperature shall be strictly controlled, which shall not exceed 120 ℃. Do not heat with flame.
15. During assembly, do not use the method of striking the non assembly ring to force the rolling element to prevent falling accuracy.
16. The bearing must be protected during and after assembly to prevent pollution and damage.
17. For other matters without rules, the relevant rules in JB / T 5000.10-1998 general skill prerequisite assembly of heavy machinery shall be implemented.
do not directly hammer SKF Bearing end face and non stressed surface, but use pressure block Sleeve or other installation tools (Tooling) make the bearing bear the force evenly, and do not install through the rolling element. If the installation surface is coated with lubricating oil, the installation will be more smooth.
If the fit interference is large, put the bearing into mineral oil and heat it to 80 ~ 90 ℃ for installation as soon as possible, and strictly control the oil temperature not more than 100 ℃ to prevent tempering effect, hardness reduction and size recovery. In case of difficulty in disassembly, it is recommended to
When you use the disassembly tool to pull outward, carefully pour hot oil on the inner ring. The heat will expand the bearing inner ring and make it easier to fall off.
You must select the appropriate clearance according to the conditions. In national standard 4604-93, the radial clearance of combined bearing is divided into five groups – group 2, group 0, group 3, group 4 and group 5.
The clearance value increases from small to large, of which group 0 is the standard clearance. The basic radial clearance group is suitable for general operating conditions, conventional temperature and common interference fit; Large radial clearance should be selected for bearings working under special conditions such as high temperature, high speed, low noise and low friction;
Small radial clearance should be selected for precision spindle and bearing for machine tool spindle; For roller bearings, a small amount of working clearance can be maintained. In addition, there is no clearance for separate bearings;
Finally, the working clearance after bearing installation is smaller than the original clearance before installation, because SKF Bearing has to bear certain load rotation, as well as the elastic deformation caused by bearing fit and load.