roller bearing slewing ring china

The Installation and Maintenance of Slewing Ring

 

1. The structure of slewing bearing

2. Preparation

1) Make sure that the model is the same with the contract.

2) Make sure the slewing ring is not damaged during the transportation.

3) Open the package in clean and dry environment.

4) The Bracket should have enough flexility to avoid the distortion of the slewing bearing and influence of its usage.

5)The installation datum plane and bracket installing plane should be clean,grease,burr,paint and other foreign bodys should be wiped off.

3. Installation

1) The screws in the installing plane should fit with the mounting holes in the slewing ring.

2) Slewing ring ball track quencher soft zone(lies between the exterior mark”S” and the jam.) is in the non-loading zone or non-regularity loading zone.Upper and lower rolling ring “s” soft zone should stagger for 180 degree. The soft zones of crane and excavator machinery should be in the place which forms a 90 degree angle with the arm support direction( the maximum load direction).

3) Put the slewing bearing on the bracket and check the contaction condition between the supporting plane and bracket with feeler gauge, level up with pad mat if clearance appeared, so as to avoid distortion after screwing down, and affect the performance of slewing bearing.

4) Before screwing down, adjust gear side clearance by gear circle radial runout vertex (3 green symbols gears), after screwing down, check gear side clearance in all the gear rings.

5) Install slewing ring with high strength Screws, and choose appropriate strength bolts by stress condition, screw down in 180 degree direction, and check all bolts to ensure that every one in the circle has the same pretightening force, not spring washer but hardening plain steel washer should be choosed in installation, screw down bolts in turn by the picture below:

6) After installation, you should wife off the dust and dunghill in the slewing ring and paint some antirust paiting,also paint some lubricate grease in raceway and gear.

4. Operation,Maintenance and Lubrication

1) Before the slewing bearings leave factory ,some No.2 EP grease (GB7324-1994) should be in slewing bearing raceway, change it into new lubricate grease according to your different working conditions.

Add grease regularly in slewing bearing raceway. Ball slewing bearing is lubricated every 100 hours, roller slewing bearing is lubricated every 50 hours, shorten the lubricate period in specially working condition, for example: in torrid zone, with high humidity, more dust, fast changing temperature and working continuously. Add enough grease before and after the the machine’s long-term stop. Fill the raceway with grease till it is seeping from the seals.turn slewing ring slowly when you add grease to make the grease equally filling.

2) Usually wipe off the foreign bodys and spread grease.

3) Check the pretightening force of the blot after the slewing bearing running first 100 hours, then make sure enough pretightening force every another 500 hours.

4) Give your attention to the running slewing bearing, you should stop it to check when noises, impulsion, abrupt accretion power appeared, and dismantle it to check when necessary.

5) Its better to protect the slewing bearings from dust, rain,water and high tempreture in operation, and defend gear engagement zone against hard objects.

6) Check the seal usually, change it when it is damaged,reset it when it is breaking off.

 

Commonly used lubricants have been list in the following table,Often lubricate the reverse with gear grease

 

Bearing Structure	Working Condition		Lubricated Parts	Lubricant
				Product	Quality Marker	Standard
Plastic insulation rubber ring seal	Low and normal temperature,moist -20℃ + 60℃		Ball Track	Extreme pressure lithium lubricating grease	No.1 No. 2	GB7323-1994
			Geared wheel	Black Lead Radical Lubrication	ZG-S	SH/T0369-1992
Metal Insulation Iabyrinth packing	High Temperature, moist	40°C ～120°C	Ball Track	Extreme pressure lithium lubricating grease	No.1 No.2	GB7323-1994
				M0S2 Compound calcium radical lubricating grease	No.2
			Geared wheel	No.4 high temperature lubricating grease	No.4	SH0376-1992
		80°～180°C	Ball Track	M0S2 Compound calcium radical lubricating grease	No.2
			Geared wheel	No.4 high temperature lubricating grease	No.4	SH0376-1992
	Normal temperature, resistance to sea～60°C		Ball Track	No.2 Compound aluminum radical lubricating grease	No.2
			Geared wheel	No.4 aluminum radical lubricating grease	No.4	SH0378-1992

 

5. Preservation

 

The slewing bearing has been sealed with oil before it leaves the factory. The packed slewing ring at optimal conditions can be stored for 6 months. Idle ball tracks need lubricating every 2 months.(please refer to “Maintance and Lubricating”).Idle slewing bearing needs oil sealed packaging every 6 months.

 

6. Oil Sealed Packaging:

1) Take out the slewing ring from the wood box.

2) When removing the wrapping, do not rip the sealing tape, remove the wrapping from the outside to the inside.

3) After taking the slewing bearing into pieces, infuse the ball track with lubricating grease.First deoil the surface and then do oil sealed packaging.

4) When deoiling, do not infuse solvent containing chlorie into sealing band and the ball track.

5) After deoiling, clean down the out surface, plaster the preservative oil and grease(F20-1) or industrial petroleum jelly(SY1607-77)evenly.

6) Then ,pack it as it was primarily done.Encase it again in the wood box.It is better to batter down a asphalt felt in the box to protect against moisture and rain.If there is no box to store the bearing, after oil sealed packaging, store it in folds.