Recently, I assisted customers to install DMD rolling mill rail system bearings on site. Due to the heavy workload, I made several sets of simple lifting tools on site. The installation operation was carried out safely, quickly and accurately with very good results. There are large four-row cylindrical roller bearings mounted to the back-up roller bearing seat, there are double row tapered roller bearings mounted with a pre-loaded spring, and middle roller and work roller bearing seat end cap spreader.

1 Four row cylindrical roller bearings mounted simple spreader

Large four-row cylindrical roller bearings are commonly used in cold rolling back-up rollers, with FCD and FCDP structural designs, and the bearing holder is designed with lifting screw holes, weighing from several hundred kilograms to several tons.

The cold-rolled large four-row cylindrical roller bearing outer assembly (FCDP structure) consists of 2 outer rings, 2 outer rings, a separator ring, and four rows of roller cage assembly (comb closed cage or common string roller cage structure), each part is numbered in order, and should be installed in order.

Common back-up roll bearings are installed by placing the bearing seat upright with the outer side open upward. Each bearing component is hoisted into the bearing seat in turn, and the bearing end face is lightened with a copper rod and then compacted with an end cover to ensure that the bearing is installed in place.If there is no suitable ring during installation, you can weld the bolt spillage on site, make 3 or 2 of each T-shaped spillage (see the cage lifting port is 3 or 4), the bolt length is 100mm, and the beam is 60~80mm (the beam cannot be left too long, there will be interference in the bearing seat after hoisting, it is not safe to hang on too short sling), in order to improve the installation efficiency, Make 2 for good.

2 Thrust double row tapered roller bearing mounting hook spreader

The current back-up roller thrust bearing is generally designed for face to face large conical Angle double row tapered roller bearing, single weight of about 150 kg or more, bearing structure is double outer ring and single inner ring roller components (inner ring and two row tapered roller and cage have been guaranteed to lock the cage when the bearing is delivered, and will not fall apart when the bearing is installed) when the thrust bearing is assembled, the bearing seat end cover is placed horizontally. The components of the large conical Angle double row tapered roller bearing can be separated, but must be installed in order to the large end cap bearing seat (installation order is: pre-loaded spring - single outer ring - double row inner ring assembly - single outer ring - pre-loaded spring - end cap compression).

Because the back-up roll thrust large cone Angle double row tapered roller bearing double row inner ring assembly is heavy, there is no operating space in the end cover bearing seat, it is easy to clamp safety accidents during assembly, and the inner ring is not easy to be straightened. For this reason, we made a set of simple hook hanger on site to facilitate the double inner ring assembly to be quickly installed in the bearing seat.

Usage is: with two hook spreader, hang the bearing cage, can be operated by two people, lift the inner ring assembly into the bearing seat, and straighten, pay attention to, the hook should be strong, can hang the cage, but also to ensure that the hook can not be too large, the inner ring assembly can pull the hook out after lifting.

3 Simple lifting device for middle roll and working roll end cover

In the middle roll, the work roll bearing installation of the rear end cover to lift to the bearing seat, because the end cover each weight in tens of kilograms, the placement process is easy to misposition and tilt, our approach: the production of two T-shaped bolt handle, can be lifted, can also be operated by two people, very convenient, accurate positioning, time and labor saving.