In many industries, chains are used to run conveyors on the oven/dryer. Proper lubrication of those chains means extended chain life, lower energy cost, and higher production rate. To lubricate oven chains, there are two options 1) Fluid Film Lubrication or 2) Solid Film Lubrication. With fluid film lubrication, when the oven runs at higher temperatures, it requires replacing the fluid lost by evaporation, oxidation, and decrease in viscosity. In such instance, solid film lubrication provides better wear protection, consumes less lubricant, and withstands higher temperature. The solid lubricant usually dispenses in the liquid carrier that is designed to evaporate after the lubricant has been applied.
This brings another challenge of applying solid lubricant on to the chain. Currently, the only way to apply solid lubricant suspended in the carrier is manually, with a spray bottle or brush. This type of manual lubrication works fine but there are several shortfalls associated with it.
- The lube technician ends up applying the lubrication unevenly. If applied too much, the lubricant will smoke at high temperature and if applied too little, chain will wear out fast.
- There are also issues with lube technician’s safety due to high temperature of the chain.
- It is hard to determine the right interval of re-lubrication.
- If lube technician forgets to shake the bottle before applying it, the solids will just stay at the bottom.
Bijur Delimon Internation and Lubrication Engineers of Canada are designing an automatic system that can apply this solid lubricant suspended in to liquid carrier. The reservoir consists of an agitator which will agitate the lubricant before pumping. The pump will transfer the lubricant from the reservoir to the distribution block which mixes air and lubricant. From there, pressurised air will carry the lubricant through tubing and to the application point. Distribution block dispenses pre-measured quantity of lubricant for even lubrication. In order to get rid of solid lubricants from the tubing after lubricating the chain, there will be an after blow of air through the tubing.
At the bearing point, stainless steel brush applies the lubricant on both sides of the chain. The liquid carrier helps solid lubricant to penetrate inside the loading areas (between the two links). After some time, carrier evaporates leaving behind solid film to protect the chain. The interval of the chain re-lubrication can be determined by monitoring the amperage draw of the motor that is driving the chain/conveyor mechanism. As soon as the amperage draw increases, it is time for re-lubrication.
The major benefit of using LE compared to other lubricant is that LE has proprietary solid lubricant name ‘ALMASOL’. It can withstand almost 2-3 times higher temperature compared to Moly, Graphite and Fluorocarbon. It has 5 times the load carrying capacity compared to graphite. Almasol has natural affinity to metal so it will stay in place longer and it is so fine that it will not build up on itself such as moly and graphite.
Lubrication Engineers has 5 different products for high temperature chains; selecting one depends on your oven chain temperature and application style. All of these 5 products can be used in automated lubrication system that ensures quick return on investment by extending chain life, lowering energy cost and increasing production rate.
Blog By Birju Shah
Adapted from ‘http://www.machinerylubrication.com/Read/1376/oven-chain-lubrication‘