How to prevent lubrication failure of industrial gearboxes?
An industrial gearbox modifies the speed of machine motors and enhances torque, as well as direction to convert energy into compatible form. It is utilized across major manufacturing industries including paper, cement, sugar and steel production factories. It is important to use industrial gearboxes in a broad range of rotary motion power transmission applications. They can perform multiple functions, regardless of duration, at the high speeds required by top-performing machinery.
Usually residing in locations like steel mills, mining operations, wind turbines etc, gearboxes tend to get affected by external conditions including extreme temperatures, vibration, and contamination. Regular lubrication of these industrial gearboxes helps in maintaining the coolness of internal components like gears, bearings, and seals. Moreover, lubrication will prevent metal corrosion and elongates the lifespan of gearbox. It also provides surface-wear protection. Most of gearbox failures occur due to improper lubrication itself.
Effects of improper lubrication of industrial gearboxes
Absence of regular lubrication or low lubrication levels however can degrade the performance of gearboxes and consequently add on expenses like repair and replacement costs. Apart from that, the charges of lost production will increase unnecessarily too.
Scuffing happens as consequence to irregular or inappropriate application of lubricating oil to industrial gearboxes. Scuffing appears like rough-edged scratches at the extreme ends of contact path where most sliding happens.
The lubrication breakdown causes high surface temperatures, due to which the scuffed region will have significantly higher austenite content than the as-manufactured surface. Scuffing also leads to large degradation of the surface’s geometry, leads to inefficiency in the system, and can potentially cause catastrophic failure.
Benefits of proper lubrication of industrial gearboxes
- Prevents wear and tear – The gears in industrial gearboxes constantly rotate. This continuous movement without the lubricating oil will lead to wear and tear in the gearbox. Leaving this unaddressed will force the company to replace or repair the gearbox. Lubrication can avoid this unwanted hindrances.
- Cools the internal components of gearbox – A gearbox has various gears that transmit torque. With constant rotation of gears, friction is produced and its excess can lead to overheating amongst the internal components. Lubrication can help in lowering the temperature and maintain a controlled friction.
- Prevents corrosion of metals – Corrosive wear causes huge damage to gearbox performance as it deteriorates the strength of gear material. A properly lubricated gearbox has less chance of corrosion and functions more effectively.
Lubrication methods for industrial gearboxes
The most common techniques of lubricating industrial gearboxes are grease lubrication, oil splash, and forced oil lubrication.
- Grease lubrication – This procedure is applicable for low speed operations, whether the industrial gearbox systems are open or closed. The grease should have appropriate viscosity, especially when its utilized for enclosed structures.
As grease does not have a cooling effect as such, you must ensure that the quantity of grease is right and as mentioned in the manufacture manual as using too much can cause delayed operations and power loss too. Whereas too less usage can cause inadequate formation of lubrication film that won’t be enough for maintenance. Grease lubrication should not be applied for heavy load gear drives.
- Oil splash lubrication – A commonly used method for helical, spur, or bevel gearboxes, these systems are dipped completely in oil bath and during the rotation of components, the oil splashes to the intended chambers, and crevices. Just see to it that the gears teeth is not totally immersed in oil as it can lead to churning. Churning is equivalent to dragging when the gears or bearings have to force through the lubricant.
- Forced oil lubrication – This is used for high speed operations and includes sub techniques like oil mist, oil spray, and oil drop process. In the Oil mist method, oil is minimized in small units so that it can saturate the gears and other internal components thoroughly.
The oil spray method applies lubricant directly to the gears and other components. This method is not always effective, as high centrifugal forces affect the direction of the oil spray.
As the name suggests, The oil drop method puts, or “drops” lube directly in the required surfaces. A pump takes lubrication from the reservoir and delivers it to the gears and/or bearings via an internal piping system. This method is similar to splash oil splash lubrication. But you can use it in case where internal components might be difficult to lubricate with oil splash method.
It is important to conduct lubrication with right techniques at correct intervals while keeping in check the signs of any possible damage, and select an appropriate lubricating oil for industrial gearbox.
A lubricant with a higher viscosity for certain operation won’t flow easily as the gear teeth engage to protect mating surfaces and provide cooling. But lubrication with a viscosity that’s too low won’t provide a sufficient film thickness to prevent metal-to-metal contact between the mating surfaces. Lubeco’s synthetic gear oils provide excellent anti- foaming, anti- corrosion & anti-wear properties and are equipped with a high viscosity index and virgin base oil stocks to upgrade and enhance the machinery’s overall performance. Contact us to know more about these products.