Gearboxes
Gearbox Repair
Gearboxes form an essential mechanical core of many motors and other devices by changing the rotational ratio between the shaft and the driver. Changing the gear ratio improves efficiency by slowing speed and increasing torque or increasing speed and reducing torque. Gearboxes are used in nearly every industrial field and are one of the most common types of repairs we see.
Unfortunately, the constant gear movement can cause wear over time. This often requires service or repairs to restore operation of the gearbox and return operations back to optimum levels.
Industrial Gearbox Repair Services
Gearboxes sent for repairs undergo a thorough evaluation and service to ensure they work well when returned to their positions in machinery. Commonly inspected and replaced parts include those that wear out quickly through normal use. Gaskets, o-rings, oil seals on shaft ends, other seals and bearings fall into this category.
Hardware may also fail during use. Repairs always include examination and replacement of damaged bolts, washers, fasteners and screws. The gears undergo a thorough inspection, during which technicians look for broken teeth, wear or backlash. Any damaged components undergo repairs or replacement to restore the gearbox’s operation.
Lastly, the gearbox undergoes testing at a known RPM. This test also ensures the gearbox works to correctly change the gear ratio. Any issues require additional inspections and repairs.
Types of Gearboxes and Their Uses
There are various types of gearboxes used in industrial applications. These have distinct applications based on their gear arrangement and design:
1. Planetary Gearboxes
The name for planetary gearboxes comes from its gear orientation. In the center, a large gear, called the sun gear, has several planet gears surrounding it that orbit the central gear during use. The sun gear’s teeth and an outer toothed ring hold the planetary gears in place.
By using multiple gears, this form of gearbox more evenly spreads the work throughout the gears, generating greater torque from a smaller area. This high torque and the gearbox’s precision combine to allow it to work for a long time with a high degree of accuracy. Many robotics and 3D printers use planetary gears for these attributes.
2. Worm Gearboxes
Worm gearboxes, also known as worm reduction gearboxes, have a heavy-duty design that permits them to drive large machinery. In these gearboxes, the input shaft is the worm or screw that meshes with the teeth of the worm gear around the output shaft. In this arrangement, the gearbox can transfer power along a 90-degree angle. Common uses for worm gearboxes include conveyor belts and elevators.
3. Helical Gearboxes
Helical gearboxes have gears inside that have the teeth cut at angles to each other. When these gears mesh, the angled teeth connect longer and at high loads along an angle. Though often compact, helical gearboxes have heavy-duty applications, especially in industries that use extruders, conveyors, crushers and coolers. All these devices use the extra power and smooth operation of helical gearboxes.
4. Bevel Gearboxes
Bevel gearboxes transfer power between two shafts at any non-parallel angles. The edges of the cone-shaped gears have mildly toothed, or beveled, edges that allow them to turn each other. With a sturdy design capable of handling high loads from heavy-duty work, these gearboxes often appear in the mining industry and railway vehicle rolling stock.
Common Problems Requiring Industrial Gearbox Repair
Industrial gearbox repairs often fall into several categories that result from the failure of one of the components. These are some of the most common failure points for industrial gearboxes:
1. Failure of Sealing Components
Several issues may contribute to the failure of seals. Dirt and debris that get into the lubricant can damage the seals by creating minute tears. These tears will lead to lubrication loss, causing additional damage to the gears and seals. When lubrication leaks from a gearbox, the internal operating temperature rises from friction-generated heat. This excessive heat can break down the seal materials, leading to extra wear.
Having the incorrect size of seals installed on the gearbox or incorrectly installed seals may create leaks which contribute to the failure of the seals and gearbox damage. Regular gearbox maintenance with frequent seal replacements can mitigate damage from dirt and debris. Only permitting qualified, experienced technicians to replace seals can prevent the improper installation of these components. Operating gearboxes in clean environments can also reduce the amount of contamination to the seals.
2. Failure of Gears
The gears themselves also need regular inspections and replacements because a gear failure can stop the gearbox’s operation or severely reduce its efficiency. As with seals, gears typically have a failure from debris or dirt entering the system. This material can get between moving parts, which causes wear on the gears and eventual failure.
In some instances, the debris results from another mechanical problem inside the gearbox, which sends shavings of metal components throughout the unit. Replacing seals regularly and scheduling frequent inspections and gearbox service can prevent this type of gear damage. Overheating can wear down gears or damage lubricant in the gearbox, causing failure of the unit. Overloading the gearbox can also lead to overheating. Avoid excessive loads to protect the operation of the gearbox.
Poor alignment of the gears typically does not happen during normal use, but following service or repairs by an unqualified person. Never allow anyone without knowledge of industrial gearbox repair to service the unit to avoid issues caused by poor maintenance.
3. Failure of Bearings
Approximately 50% of gearbox problems stem from bearing failures. Reasons for bearing failures include improper lubrication and overloading the bearings. Excessive force on the bearings can occur from too high of a load exerted on the shaft. The bearings take much of this extra load, contributing to damage from overuse.
During repairs, technicians will inspect the bearing races ball paths for signs of this type of excessive force. If found, they will replace the bearings. To avoid this type of problem, operators should only use gearboxes within load limits.
Lubrication problems can also damage the bearings. Too little lubrication can cause a buildup of friction heat from the metal bearings running along the metal track. Over time, this metal-on-metal contact will wear out the bearing race, leading to complete failure. Having too much lubrication also causes issues with the bearings through thermal damage caused by fluid friction.
During maintenance, checking the bearings for the proper amount of lubrication can prevent damage to the bearings. Only allow qualified technicians to repair and maintain bearings to ensure the longevity of these parts by avoiding friction damage.
Contact Global Electronic Services for Gearbox Repairs
At Global Electronic Services, we provide all the gearbox maintenance services and repairs your company needs to keep machinery working at its peak efficiency. There’s no one else you need. Our industrial gearbox repair experts will do it right and fast at a price you can afford.
To get started with industrial gearbox repair services, contact us online or call 877-249-1701 to request a free quote for your repairs today.