What are Rotec or Slewing Bearings?
Rotec / slewing ring bearings, also known as turntable bearings, are composed of two concentric rings either of which may include a gear. They are designed to enhance load support and power transmission in all directions allowing for independent movement of the upper house and the undercarriage (tracks) of your Hitachi and John Deere excavator.
Design Features of Rotec Bearings
Rotec bearings are designed for heavy loads and endurance so that they will provide your excavator with long service life. In order to handle heavy loads, they also feature high stiffness for rigid bearing application and low friction. Moreover, Rotec bearings are designed with surface protection and corrosion resistance to extend their service life.
However, the high demands and difficult challenges of some projects can cause premature failures of large-diameter Rotec bearings where rotations are frequent. This is due to the fact that they are used to manipulate a wide variety of loads and perform diverse combinations of thrust, radial, and tilting moment loading. As we have mentioned numerous times regarding the prevention of parts failure, with regular maintenance, you can prevent a large part of Rotec bearing failures.
Actions that Can Protect Your Rotec Bearings
Frequent Lubrication
Lubricating your Rotec bearings as part of your regular maintenance program with heavy-duty, extreme-pressure grease will minimize the possibility of issues or costly failure. Manufacturers usually suggest that you lubricate the fittings around the bearing’s circumference – how often this should be done can be found in your excavator operator’s manual. You should expect that you will be required to lubricate more frequently excavators that make rapid movements rather than slower-rotating ones.
Purge Old Grease
Keep in mind that when you lubricate your Rotec bearings, you should do it in a way that you will purge the old grease since it has contaminants. This means that when you are greasing, the bearings should rotate them to spread the grease throughout until you can see the old grease squeeze past the seal. It’s also a good idea to rub some of the old purged grease between your fingers to feel for grit or metal chips. If you do notice grit you may have a bearing problem so you should investigate. Also, keep in mind that grease can dry out over time and allow condensation to form within a bearing. As a result, even if your excavator is sitting idle, you should grease the Rotec bearings at least every four to six months.
Lubricate Gears
If your Rotec bearings have gear teeth, then you must lubricate them as well but it may be necessary to lubricate them more often. Since the meshing action of the teeth has the tendency to squeeze out lubricant, the gears should be lubricated every eight hours of operation for slow-rotating excavators and more frequently on rapidly or continuously rotating excavators.
Check the Torque of Bolts
As part of your maintenance program, you need to check that the torque of bolts of your excavator’s Rotec bearings is at an ideal level. How often you need to check the bolts, normally depends on how hard you work your excavator. If you conduct work during which your excavator experiences intense vibrations, such conditions can loosen bolts. However, with frequent torque checks and tightening, you can help maintain a proper preload level and avoid possible damage to your excavator or even injuries to your operators.
It’s also important to remember that bolts that are under stress or exposed to high temperatures due to friction can experience the phenomenon of “bolt creep.” Stress, heat, and frequent tightening can cause bolts to creep over a period of time, reducing preload.
Check the Seals of Your Rotec Bearings
As with all excavator seals, you need to make a visual check of the seals of your Rotec bearings to ensure they are functioning properly. The seals of your excavator Rotec bearings maintain/retain the lubrication level of ring and bearing tracks. The seals also protect them against dust and the intrusion of contaminants. Therefore, by checking the seals you can prevent bearing raceway contamination and keep them properly lubricated.
Last Word
By being proactive and conducting regular preventive maintenance, you can protect your excavator’s Rotec bearings and save yourself a lot of hassles and money. Proper maintenance of any excavator part is vital since it will help keep your excavator working productively and prevent breakdowns that can result in costly downtime and repairs. At Langley Excavator Parts Exchange, you’ll find new, rebuilt, refurbished, and used excavator components and parts, including Rotec bearings, for John Deere and Hitachi excavators. Our expert technician will find what you need quickly and help minimize downtime. Call us at 1-888-530-5444 or contact us online. With one of the largest inventories of John Deere and Hitachi components, our experienced and knowledgeable staff is equipped to help you with the part you may need.
