Getting recycling taped - but not all wrapped up
ERIKS sealing and bearing know-how made finding a solution relatively simple.
Once people used to throw their rubbish away and think no more about it. It was 'somebody else's problem'. Now they recycle it instead, and still think no more about it, because it's still somebody else's problem. In this particular case, the problem was a tricky one for an environmental waste recycling company.
The reasons for what is recycled and when can be traced back to changes in tastes, technology or recyclability. The demise of video tapes and their replacement with DVDs has led to a surge in the recycling of the tapes, and that in turn led to difficulties for one recycler.
Tape has to be separated from paper, and other rubbish. This takes place on conveyors, which are driven by rollers. Unfortunately, the video tape frequently comes unravelled from within the tape cassette and subsequently wraps itself around whatever it comes into contact with - including the conveyor rollers. The tape works down the rollers and binds up at each end by the mounting bearings.
This can have one of two results - both of which can lead to expensive downtime, or even worse.
The tape can bind up so tightly that it forces the metal bearing seal into the rolling elements, causing the conveyor to stop and to be unable to start again until the tape has been unravelled. Or, worse still, the tape can jam and cause huge friction and heat: enough heat, in fact, to ignite a fire. Norwich's waste recycling site caught fire
for this very reason.
One environmental waste recycling company sought help from ERIKS, whose sealing and bearing know-how made finding a solution relatively simple.
Realising that the tape had to be prevented from building up, and the bearing had to be protected, ERIKS recommended the use of a PTFE disc matching the profile of the external part of the bearing seal, to be located over it. Since PTFE has a melting point of 327°C, and the lowest coefficient of friction of any known solid material, this makes it almost impossible for the tape to stick to the bearing. Even if it does so, it makes the possibility of ignition highly unlikely.
The recycling company accepted ERIKS' recommendation, and once the PTFE disc was installed there was no incidence of tape binding round the roller bearings in the first four months of operation. As a result, if further tests prove satisfactory, the company intends to fit the seal to all conveyor rollers.