1. Wear condition of large rotary bearings

During the maintenance of the bucket turbine, the maintenance of the rotary bearing is an important link. During the maintenance process, it is found that due to the poor lubrication system and the poor sealing condition, there are residues entering the bearing track, and at the same time, there are punctate and annular wear traces in the position of the roller contact, as shown in Figure 1 and 2.

Fig. 1 Point wear

Fig. 2 annular wear

2, rotary bearing wear reason analysis

Large rotary bearings in the bucket turbine bear relatively large load strength, long-term operation will bring great damage to bearings, and the reasons for the failure of rotary bearings in the working process of the bucket turbine are as follows:

(1) The rotary bearing of the bucket turbine has been used for a long time, and some small problems have not been paid attention to in the maintenance process. For a long time, the accumulation of problems has resulted in the formation of major failures.

(2) the reclaimer's work, in the process of repair and maintenance work of it, not in time to make the working process of the reclaimer's some small problems in the report is not timely maintenance, and turbine maintenance cleaning work does not reach the designated position makes fights the turbine slewing bearing inside there are a lot of dust, affect the rotation of the bearing, slewing bearing fault;

(3) the bucket turbine in the process of transport, overload transport goods, making the performance of the bucket turbine damaged, thus causing the failure of the bucket turbine.

3, bucket turbine rotary bearing overhaul steps

For large size and not easy to handle, like the reclaimer's machinery and equipment, when it fails to repair when the repair work must be ready for work, dou turbine are different from other small mechanical equipment, repair bad to can extend the time to repair, it cannot leave transhipment worked for a long time, leaving a long time and terminal transport work will be faced with the threat of paralysis, the introduction of new fighting turbines, in most case, it is not real, so can shorten repair time, ready to repair before work.

(1) the preparation work before the maintenance of the rotary bearing of the bucket turbine

First of all, the rotary bearing of the failed bucket turbine is jacked up through the hydraulic kilo in order to extract the horizontal shaft of the rotary bearing for inspection and maintenance.In one thousand jins bumps up the slewing bearing should pay attention to hold the jack's base, avoid jack skew the slewing bearing slump cause serious accident, so in the process of preparation is to jack fixed, and then according to the need to build a solid support or pier and other supporting artifacts, must guarantee after repair, dou turbine into work, built by stent and pier does not affect the normal operation, build good stent and pier need not dismantle, later reclaimer's troubleshooting, save costs and save time.

(2) carry out disassembly and maintenance work

Established after reclaimer's removal of the stent removal process, must guarantee maintenance around there is enough space to hold removed dou turbine parts, walking round with a solid steel card, to prevent the shaking, then one by one the reclaimer's coal tube, inside and outside of the cable, gear cover and clean the oil within the tank release, open the tank to remove the bearing bolt through the preparation of the workpiece remove slewing bearing, for fault analysis and repair it.

(3) the installation of rotary bearings

Will repair good slewing bearing mounted to the turbine, during the installation process to strictly check the slewing bearing inner and outer circle the connecting bolt, to not meet the requirements of the safety bolt must be replaced with a new bolt meet safety requirements, after qualified inspection during installation, for steel plate thinner tank, in order to ensure the toughness of the groove so in the tank

After opening it, try to replace it with a new oil groove, because the welded oil groove is very prone to failure after long-term use. In order to avoid secondary failures, the oil groove will be replaced with a new one as far as possible to reduce the number of bucket turbine failures.When the installed bucket turbine is put into operation, it should be tested first, and it can be put into work only after passing the test.

4. Matters needing attention when repairing rotary bearings

First of all, we should pay attention to the lubrication effect of the bearing raceway in the maintenance process of the rotary bearing. For a large rotary bearing, if the lubrication effect of the narrow and long raceway is not good, it is not only long

Roll since the dust accumulation within the tao will affect the bearing, the raceway of lubricating oil is difficult to play its effect, so that even if the slewing bearing is fixed, when put into use in the will because of his bad race lubrication effect again bearing wear, and over time the bearing will fail, so be sure to pay attention to the bearing raceway lubrication and cleaning, lubricating grease add methods, try to reduce the bearing wear.

Second, dou turbine slewing bearing wear occurred in addition to race affect the lubrication effect, the reclaimer's upper body due to balance the moment there is a deviation, make the bearing in the roll surface wear is more serious in the tiny, so when maintenance should pay attention to the upper body weight, to reduce the deviation of reclaimer's upper body balance torque.

Finally, we should pay attention to the installation of local tempering belt of the inner and outer ring of the bearing. We must not install the inner and outer ring tempering belt superimposed on each other. We must staggered them to reduce the bearing bearing bearing bearing bearing bearing resistance and reduce the wear of the tempering belt on the bearing operation process.