high quality china slewing ring
Table of Contents
1.Slewing ring Installation
When you get LYMC slewing ring, please mount slewing ring as instructions below:
(1)Require the installation surface has sufficient strength and rigidity.
(2)Clean bearing and surface of the components, each surface can not have corrosion.
(3)The mounting surface should have locating pin or locating mouth, to prevent the bearing ran to each other.
(4)After contact with the mounting surface, you should check fit clearance with a feeler, the gap can be filled with plastic or a padded to prevent deformation of the bolt tightening.
(5)When installing, ensure that the bearing quenching soft belt should be located in the non-load bearing area or not often load area or load minimum area.
(6)Bearing mounting bolts must be of high strength bolts, according to the loading conditions, select the appropriate intensity level.
(7)Installation washer should adopt flat washer to ensure bearing pre load uniformly.
(8)Bolt preload requires sufficient strength, the preload force is 0.7 times to the bolt material yield limit. Best installed using a torque wrench to ensure uniform force and improve quality of the installation.
(9)Tighten bolts should adopt a “star” cross or symmetrical diagonal tightening way, first pretension and then follow the strength requirements and tighten the bolts.Tighten the bolts needs a torque wrench .
(10)For toothed products,must do the gear backlash detection before tighten the mounting bolts. To ensure the minimum or maximum diameter (with logo) of the gear ring beating meet the design requirements (available 0.05 ~ 0.3mm feeler gauge calibration) .
Slewing ring installation related parameters requirements
(1)Mounting surface roughness is less than Ra12.5.
(2)The maximum allowable values of the installation surface flatness can be determined according to actual working condition, but the flatness change must be uniform increasing or decreasing, within the scope of the circumference of a circle, not allowed to appear more than two (including two) peak, and 100 mm face runout is not allowed within the scope of more than 0.015 mm
(3)Maximum value on the radial direction inclination of the mounting surface is 0.04mm .
(4)Prestressing force of bolt installation must be determined according to the strength level of the bolt,the pre load force is 0.7 times to the bolt material yield limit.
Structures with slewing bearings normally require design types which are able to transmit all occurring loads with one bearing. These are normally axial, radial and tilting moments.These bearings must furthermore be suited to withstand the complete spectrum of operating conditions, as for example
• High and low temperatures including temperature fluctuations
• Overpressures and negative pressures
• Deformations of the companion structure
• Weight limits
• Limitation of the frictional torque
• Low maintenance
• Corrosion resistance
• Magnetoresistive behaviour
• Open center to run through supply lines or as access opening
Design and dimensioning
The bearings are individually designed and dimensioned for every application, this means that the buyer is not required to customize to specified geometries of catalogue bearings and characteristics but the bearing can be designed according to the customer’s structure and the specification.
2.Heat Treatment of Slewing ring Steel
Heat treatment of slewing bearing steel is to put solid metal or alloy into certain medium then undergoes three process: heating, heat preservation, and cooling to change steel organization and get required performance.
Different from other processing technology (such as forging, casting, welding, machining), purpose of heat treatment is not to change shape and dimension of steel but to change internal organization and performance of steel.
Heat treatment is alternately and repeatedly used among cold working, hot working, and other manufacturing process of mechanical parts or dies. According to its application, Heat treatment usually divided into pre-heat-treatment and final heat-treatment, and location of processing line as bellow :forging/casting→pre heat treatment→machinery (rough) processing →final heat treatment→mechanical (fine) processing.
Final heat treatment, such as quenching+tempering, etc, known as the heat treatment that enables the workpiece to meet the performance requirements under use condition. Pre heat treatment, such as annealing, normalization, known as the heat treatment that eliminates defects caused by former process or get organization and ready for subsequent machining and final heat treatment.
3.The correct storage method for slewing ring
Slewing rings are coated with anti-rust oil , and wrapped with a film in the factory. Such a package is usually valid for 3-6 months antirust.As long as the relative humidity does not exceed 60% of the storage compartment , the temperature changes within(20 ± 10), slewing ring general can store about a year (in the original packaging in good condition ) .
After long-term storage , grease lubricating properties of slewing bearings’ raceway filled may reduce.Before using the slewing bearing,they need to be filled with a new grease filling, storeroom should also avoid vibration and shaking.
For slewing rings ( turntable bearings ) not stored in their original packagings they should be kept well, to protect against corrosion and contamination .
For large slewing rings should be on flat, and inner and outer rings both should be supported. It should be stacked flat isolation between slewing rings.
