A, lubrication method
Bearing lubrication principle with the other bearing lubrication basically the same, just the bearing operating conditions are relatively poor performance of its ability to obtain effectively depends largely on the bearing lubrication.
Bearing lubrication methods are mainly used grease and oil lubrication.
Both grease lubrication grease seal, sealing and lubrication facilities, simple structure, easy to add grease, so long as the working conditions allow, the bearings are generally lubricated with grease.
The cooling effect of strong oil lubrication and bearing away from dirt and moisture. Bearings with oil lubrication methods are pressure lubrication, fuel injection lubrication, oil mist lubrication and oil lubrication.
Pressure lubrication is the conventional speed bearing the most effective lubrication.
The oil injection lubrication is a certain pressure through the nozzle mounted on the bearing side sprayed into the interior of the bearing lubrication, generally used in high-speed bearings, or pressure lubrication can not meet the cooling requirements of the occasion.
Lubrication is spray drying of compressed air containing oil mist sprayed into the bearing for lubrication, using less oil, the role of the air, the cooling effect is very strong, mainly for the rolling speed is high and a high precision large rolling bearing, or for the bearing housing is not frequent removal of the bearing.
Pressure lubrication and injection lubrication requires installation of inlet and outlet tubing, lubrication pump, oil reservoir, oil cooler and sometimes need, therefore, higher cost, generally bearing less used.
B, Configuration Type
(1), self-aligning roller bearings
Early in the rolling mill bearing types and configurations on different now, was mainly using two self-aligning roller bearings mounted side by side on the same roll neck. This configuration type basically meet the prevailing production conditions, rolling speeds of up to 600rpm. But as speeds increase, more prominent drawback: short bearing life, consumed in large quantities, finished low precision, roll neck wear serious, and large axial movement.
(2), four cylindrical roller bearing + thrust bearing
Cylindrical roller bearings and roll neck diameter of a tight fit, radial force, with a load capacity, high limiting speed, high precision, detachable and interchangeable inner and outer rings, easy processing, low production cost and easy installation and removal ; thrust bearing axial force, the specific structure type can be selected according to the characteristics of the rolling mill.
Heavy at low speeds, with thrust roller bearings, with a smaller axial clearance to bear the thrust load. When the rolling speed is high, with angular contact ball bearings, not only the high speed limit, but when working axial clearance can be strictly controlled. So get close axial guidance, axial load can withstand normal force.
This not only has a bearing type bearing arrangement long life, high reliability, and has rolled products of high precision, easy to control, and many other advantages, the most widely used, and more for wire rod mill, lumber mill, foil mill, two support rollers cold rolling mill and hot rolling mill machines and other supporting roller.
(3), four-row tapered roller bearings
Tapered roller bearings can support radial forces, but also to withstand the axial force, no need to configure the thrust bearing, so the host is even more compact. Tapered roller bearings and roll neck diameter using a loose fit, installation and removal is very convenient, but sometimes due to sliding creep caused by a loose fit, so often processed with a spiral groove diameter.
This configuration type of the current application is still relatively wide, such as four-roll rolling mill and cold rolling mill work rolls, blooming machines, structural steel mill and other occasions.
Product Model | Inside Diameter | Outside Diameter | Thickness |
7205CDB NSK | 25 | 52 | 15 |
7205BDB NSK | 25 | 52 | 15 |