Page 92 - The Jet Engine

Lubrication

Fig. 8-12 A typical pressure and scavenge filter.

29. To prevent foreign matter from continuously pump outlet which retains any small particles which
circulating around the lubricating system, a number could block the oil feed jets. Thread-type filters (fig.
of filters and strainers are positioned within the 8-11) are often fitted as a 'last chance' filter
system. immediately upstream of the oil jets. Sometimes
perforated plates or gauze filters are used for this
30. Coarse strainers are usually fitted at the outlet application, Scavenge filters are fitted in each oil
of the oil tank or immediately prior to the inlet of the return line to collect any debris from the lubricated
oil pumps to prevent debris from damaging the components. An example of a pressure and
pumps. A fine pressure filter is fitted at the pressure scavenge filter is shown in fig. 8-12. They are

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