MetOcean Telematics MMI-513-00000, User Manual, Page: 36 / 56

iBCN – User Manual
TD 13 – 053
34
7.4 “O” Ring Facts
The main problem with “O” rings is that over time they
can take a “set” shape. They lose their original round
shape and they become slightly flattened resulting in less
compressibility.
Reduced compressibility can lead to a water leak. The
best way to prevent a problem is to service the “O” rings
before every deployment.
Some of the main factors that can cause a “set” are:
•
High storage temperature (exceeding 40
°
C) over
time will cause the rubber to harden.
•
Exposure to sunlight and ozone will cause the “O”
ring to deteriorate and stiffen.
•
Temperature does not have to be that cold for an
“O” ring to lose a great deal of its flexibility. At 4
°
C,
an “O” ring has stiffened significantly.
•
“O” rings must be lightly lubricated with silicone-
based grease. We recommend “Parker Super O
Lube”.
•
A typical seal failure results in a very small amount
of water, not a flooded case. Most seal failures
occur near the surface.
•
The “O” ring becomes less flexible as the rubber
ages.
•
If you are operating or storing at low temperature,
it makes it even more important to service the “O”
ring regularly.