The running of the chain around the wheels causes wear of the articulations by the angle – slide movements of the
bolts. Due to that fact lubrication of articulated chains is important to guarantee long life time and satisfactory
service. The lubricant satisfies several functions: It separates pins and bushes surfaces, allowing easy rotation,
then it damps and decreases sudden shocks between pins and bushes and chain and wheels and it might cool
and clean the chain.
To obtain a good lubrication, oil must penetrate into articulations (B); it is not enough to lubricate the rollers (A). Oil
must be applied to the inside surfaces of the chain at the edges of the link plates.
A pure mineral oil is recommended. Heavy oils and grease are not recommended, but may be foreseen for
special applications (especially if the surrounding conditions contain dust, like lime, flour, talcum etc). We
recommend the following lubricant viscosities for different temperatures: Please see table above.
For higher temperature applications (over 200°C) powdered graphite in an evaporating vehicle is recommended.
For heavy load it is advisable to use high pressure oil.
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Basically:: |
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low joint surface pressure, high chain speed:: |
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low viscosity |
| high joint surface pressure, low chain speed:
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high viscosity |
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low temperature: |
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low viscosity |
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high temperature: |
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high viscosity
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Four basic types of lubrication are recommended as following recommendations correspond to the minimum advisable;
it is always possible to use the immediate superior lubrication type):
- Manual lubrication: For speed up to 0.5 m/sec. Oil is applied with an oil can or brush, periodically (advise once
every 8 working hours).
- Drip lubrication: For speed up to 1.5 m/sec. Oil drip delivery should be regulated to assure uniform lubrication
between 4 and 10 drops per minute.
- Oil bath or disc lubrication: For speed up to 8 m/sec. In oil bath the lower strand of chain runs through a bath
of oil whose level is kept at about the chain pitch line (deeper dipping is not allowed due to warming and oxidation
of the oil). Disc type lubrication uses a rotating disc dipping in an oil bath. The disc picks up oil from a
sump and deposits it into the chain. The disc diameter shall be selected to keep a rotatif speed of 3 m/sec.
minimum to 40 m/sec. maximum.
- Forced lubrication: For speed more than 8 m/sec. Forced oil feed lubrication is the most effective system. Oil
is supplied under pressure by a pump and continuously sprayed onto the chain. The oil should be applied
inside the chain loop and at the lower strand just short of the point of engaging the sprocket.
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1. Manual lubrication |
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2. Drip lubrication |
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3. Oil bath or disc lubrication |
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4. Forced lubrication | |
