China Whole Sale Popular Bucket Turbine Slewing Bearing

10 Tips for Replacement, Maintenance and Installation of Bucket Turbine Slewing Bearings

Based on the domestic bucket turbine slewing bearing 1797/3230G2K and the stacker-reclaimer slewing bearing 1797/2635, 1797/2500G, and 132.40.3550.12, 10 tips for the replacement, maintenance and installation of bucket turbine bearings are analyzed.

Analysis of Damage Causes of Rotary Large Bearings
The reasons for the damage of the large bucket turbine slewing bearing are:

(1) The large bearing has been running for 8 to 12 years, and the cycle is long, and the defects have been exposed during the overhaul;

(2) The foundation of the walking track of the bucket turbine has been running unevenly for many years. Shen, the bearing is in an inclined state when working, and is subjected to additional force to accelerate wear;

(3) Bearing
The vulcanized rubber seal is aging, and dust enters the inside of the bearing; (4) Overloading when coal is taken.

Item Lift Replacement of Slewing Large Bearings
Use the “lifting method” to replace the large slewing bearing of the bucket turbine by yourself: lift the part above the slewing unit as a whole and replace the Bucket Turbine Slewing Bearing.
Ready to work

The weight of the part above the slewing platform of the bucket turbine is about 270 t-350T, and the cantilever is 30m long. Although there is a counterweight mechanism, the center of gravity of the part above the slewing platform is still inclined to the cantilever – – side, and the distance between the center of gravity and the geometric center is about 0.5 m.

The cantilever must be erected, and the cantilever wire rope is slightly loosened, so that the center of gravity of the upper part of the slewing platform is closer to the geometric center, and the unbalanced force during jacking is reduced.

For this reason, on the south side of the vertical direction to the bucket wheel machine running track,The coal is piled up to about 2m above the level of the cantilever 2 months in advance. After sun exposure, rain, compaction, the cantilever supports the shelf when the bearing is replaced, which can reduce the tooling cost.

Bucket Turbine Positioning
Keep the bucket wheel cantilever perpendicular to the track, lift the cantilever, and walk the bucket wheel to the predetermined position. At this time, the front end of the bucket wheel cantilever falls on the coal pile stacked in advance (a suitable sleeper is placed between the coal pile and the cantilever), so that the cantilever is covered by coal. Stack up.

At this time, the wire rope of the counterweight mechanism is loosened, but cannot leave the pulley channel. Special attention: The tightness of the wire rope should ensure that when the upper slewing platform is jacked up to 180mn, the wire rope is still slightly loose, and the weight of the cantilever head still falls on the coal pile.
In order to maintain the balance and stability of the rotary platform. .

Fixed bucket wheel

Considering that the walking track of the bucket wheel machine is not very flat, and the bucket wheel machine may be affected by wind during construction, and the external force of the bucket wheel machine when the large bearing enters and exits, the lower body of the bucket wheel machine must be fixed with a rail clamp before construction.

At the same time, along the direction of the track, 22mm diameter steel wire ropes are used to pull the ground foundation on both sides of the height of the door beam to increase the stability of the upper body. The middle of the steel wire ropes are respectively connected – – – only pull the 3t hoist by hand, and adjust the tightness of the steel wire ropes at any time during the next lifting process of the rotary platform.
Remove accessories

The coal drop tube, cantilever belt electric drum and head guard on the rotary platform, the coal drop tube of the rotary platform is connected to a fixed coal drop tube with a length of about 500 mm, which affects the replacement of large bearings and needs to be removed. Power cables must be carefully pulled out of their protective sleeves and then cut off.
ready to lift

Each of the 4 jacking blocks is arranged – a 100T screw jack, and the jack can be lifted until it is evenly difficult. Four-corner welding is used as a steel pipe for guiding and positioning as well as a ruler. The special steel pipe is inserted into the lower steel pipe, and the two types of steel pipes are welded on the upper and lower jacking seats respectively. Then, first loosen the 36 M36 bolts on the outer ring of the large bearing.

Note that it can only be loosened at this time, because the space height is not enough, and the bolts are still inserted in the bolt holes of the large bearing. Then loosen the inner ring bolts, 36 M36 inner ring bolts are temporarily reserved for 6 evenly distributed and cannot be loosened.

Because 36 bolts of the outer ring of the lBucket Turbine Slewing Bearing are connected to the lower fixed platform, 36 bolts of the inner ring are connected to the upper slewing platform, and the inner and outer rings of the large bearing are connected to each other with 6 M24 bolts.

The key lifting, the time must be controlled within 1 day. (10 hours)
After all the parts that affect the replacement of the Bucket Turbine Slewing Bearing are removed, the 4 jacks will be lifted synchronously under the command of – – Human System – -.

During this process, pay close attention to the readings of each scale, the maximum error is controlled within 2 mm, and as required Adjust the tightness of the air line, stop when the upper slewing platform (the Bucket Turbine Slewing Bearing is still connected to it) is jacked up for 180 mo, and the jacking seat is temporarily welded with steel pipes up and down to ensure that the upper and lower platforms have no relative displacement.

Then, use 3 lifters evenly distributed on the fixed platform below the large bearing, slightly against the large bearing. At this time, the remaining 6 bolts of the inner ring can be disassembled, and the track lifter evenly drops to a distance of 6-8mm from the lower fixed platform.

The rear of the large bearing is connected to the tail car with a wire rope and a hoist, and the front part is pulled along the horizontal direction of the track. A traction Wire rope, inserted horizontally between the large bearing and the lower slewing platform – a 25mm steel pipe is used as a roller, and the length is equal to the outer diameter of the large bearing.

Continue to drop the elevator until the large bearing falls on the roller. Under the protection of the machine, remove the lifter, and use the head to pull the wire rope to slowly pull out the large bearing to two-thirds of the large bearing.
Backpack
Push in the new bearing in the same way as above, and assemble and adjust.

Practice has proved that the replacement method for the large bearing of a bucket turbine is successful, and the construction period is only

It takes 6-9 days and costs 100,000-160,000 yuan, which not only ensures safety, but also saves money, and improves the replacement procedures and processes. after replacement
After more than 1 year of operation, the rotation is stable, the large and small gears are well meshed, the operation is normal, and the rated output is reached.