50 / 222
البحـث الأول
مجلة النفط والتعاون العربي
161
العدد
- 2017
أربعون
المجلد الثالث و ال
2016
أوابك العلمية لعام
�
ص لبحوث العلمية الفائزة بجائزة
�
عدد خا
43
33
The Drain Interval:
In the early days of the lubricating oils, mineral oils were simple and contained
no additives. Therefore they required frequent changes as their contamination and
deterioration were faster. Engine oils were changed at that time at no more than
500 miles
30
(800 kilometres) distance travelled. However, with advancement
made in production processes and the availability of chemical additives to
improve performance, drain intervals became longer.
It is now the intention of many governments and the industry to reduce lubricating
oils consumption by extending the drain period in all fields in order to conserve
a valuable resource and to reduce the environmental load that is associated with
the volume of used oils
4
. This is becoming a priority
32
and more and more
possible by the availability of high quality lubricants and cleaner fuels
30
. It is
especially true in developed countries of Europe and North America and the
developing regions are catching up as outdated motor vehicles and machinery are
replaced with products that require smaller amounts of better-performing
lubricants
4
.
In the advanced countries, in the heavy duty diesel engine category, oil drain
intervals remain around 25,000 miles though it is possible to double this mileage
30
for normally running vehicles. However, for the same vehicles running in more
severe and harsher conditions, an oil change by 15,000 miles is in order.
Tests conducted in 2010 on trucks with MaxxForce engines showed that oil
change can range from 18,000 to 40,000 miles
30
. But in reality the answer lies in
the operator’s ability to monitor
the quality of the oil through on board diagnostics
or oil analysis to increase his fleet’s drain period gradually and prudently.
In the passenger car field
the majority of automakers today call for
oil changes
at
either 7,500 or 10,000 miles
29
. This is in contrast to the US where the general
practice is changing oil at an outdated 3000 miles target. Some manufacturers still
recommend 5000 miles depending on the quality of oil. When synthetic oils are
used the change interval can extend from 7500 miles to 25000 miles depending
on the type of synthetic oil used
32
.
The trend for extended oil changes has influenced lube oils producers to process
more hydrocracked oils that have similar performance characteristics to those of
synthetics as we saw earlier.