Originally Posted by 4vvard

Enviromental impact of reduction drives and lubricated bearings

I am designing a converyor belt in University, and as part of the excersise I have to take

into consideration que whole life of the product, considering all emissions that my design

might have.

I have never worked with converyor belts, and I have a few questions concerning the emissions

from reductions drives and grease lubricated bearings.

My question is, at every new lubrication of a reduction drive and bearings, is the old grease removed?

Where does it go? Does it slowly seep out or dry up, or does one have to change the grease leaving one with spent grease?

Thanks.

As far as emmisions from lubricants are concerned they are actually minor in the

entire scheme of things.

The chemical refining of the petroleum distillates that become the heavy lubricating oils

and greases creates greater emmisions.

NOW:

Heavy gears oils like 90 weight gear oils are used for lubrication of roller chains and gear sets

that spin the drive pulleys.

When you get into lubricating of large bronze turntable castings/slewing bearings

that have been machined hydraulic oils are used and fall to the ground after they

reach the outer perimeter of the bronze bearings.

The same thing occurs with lubricating greases as well.

Now as far as roller bearings go Most roller bearings use heavy greases to keep the bearings

cool and lubricated. Over time the heat from the rotation of the bearings breaks down the

grease and it need to be replaced with fresh grease.

Bringing you to this point the grease breaks down and simply falls to the bottom of the sealed bearing housing.

As far as gear oil and chain drives and opposing gear drives the gear oil splash lubricates the roller chains

and gear pairs.

This oil simply rests inthe catch pan that also acts as an oil reservoir at the same time.

NOW the next point is high speed light oil lubricated bearings.

These bearings have labrinth seals that holds the oil in place and need

to be changed annually normally.

As far as any grease that passes through the seals it simply falls to the ground unless drop pans

are used. The same can be said for gear lubricating oils. ■

While the environmental aspects of spent lubricants are possibly minimal, depending on the quantities involved, the Health and Safety implications can be quite severe. Treading grease of heavy oil underfoot can, does, induce slips or falls. Depending on the location of the discarded lubricant the damage can be considerable. Also most mineral lubricants are not kind to rubber compounds chemically and frictionally. During construction works it is often, nearly always, written into the contract that all debris must be safely disposed of. After the site is handed over the maintenance people, almost without exception, discard that principle and try to make the plant resemble a warzone. In that context you might like to consider randomly discarded lubricant as a booby trap.

When I was first introduced to conveyors, and thereafter, it was customary to provide safe and adequate drains for gearboxes. ■