THE ANNALS OF UNIVERSITY DUN ĂREA DE JOS OF GALATI [601399]

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
124

Paper presented at the

International Conference on
Diagnosis and Prediction in Mechanical
Engineering Systems (DIPRE’09)
22 – 23 October 2009, Galati, Romania

RAPESEED OIL FLAMMABI LITY ON HOT SURFACE

Lorena DELEANU, Sorin CIORTAN, Liviu C ătălin ȘOLEA

University “Dun ărea de Jos” Galati, ROMANIA
[anonimizat]

ABSTRACT
The paper presents the tests and results upon rapeseed oil flammability on hot surface. The oil samples were obtained from a rapeseed oil after a dewaxing
process. There were established temperature ranges for which the oil samples could get one of the three qualifications, as expressed in SR EN ISO 20823:2004.

KEYWORDS : Rapeseed oil, flammability on ho t surface, flammability test,
SR EN ISO 20823:2004.

1. INTRODUCTION

Romania is the 15th world producer of rapeseed.
Analysing the UN Food & Agriculture Organisation
statistics, among the first 20 countries producing rapeseed, there are 10 countries from the European
2007
0.000 2.000 4.000 6.000DEFRPLUKCZDKHUROSKSE
Rapeseed production (million tones)

Fig. 1. Rapeseed production of UE countries in the
top 20 world producers [6]. ISO 3166-2 code
Alpha-2 symbols for countries’ names. Union, their sum production being 17,137,511 tones
(fig. 1) that is 86.5% of the production volume of the
first two countries (China and Canada) and almost
34% of the world total [6].
These facts underline the increasing interest for
producing and using rapeseed oils, not only for food,
but also for industrial applications as lubricants and bio-fuels [7, 10, 16, 17]. O il-seed crops (for example,
rape-seed, soybean and sunflower) can be converted
into methyl-esters, which can substitute normal fossil diesel, and they can be used in their pure or blended
states [17]. The success of vegetal oils is related to
their biodegradability and reduced toxicity, but a
wide use is limited by a set of properties being of
great interest for industrial applications, including their unsatisfactory stability in time [12, 15].
At present, the use of pure (non-altered) vegetal
oils is limited only for applications with total loss of lubricants, such as chain saws lubricants, oils for
moulds and hydraulic fluids, with a low level of ther-
mal and mechanical stresses [10, 21]. The usage of
fast biodegradable lubricants represents an ecological
advantage, but also an economical one. Unfortu-
nately, the presence on the market of these materials
is relatively low. Figure 2 shows the total USA
vegetal oil and animal fat consumption in 2007 [18].
A market study shows that the share of non-polluting
hydraulic fluids, based on vegetal oils, increased in
2000 at 8% and the tendency is maintained [12].

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
125

Fig. 2. Total US vegetal oil and animal fat
consumption (15.0 billion kg/year) by source (Bureau
of Census, USDA-ERS) for 2007-2008.

Selecting a fluid for an application includes not
only high level of performances for the main aim (lu-
bricant properties as viscosity and viscosity index etc.
for tribosystems, thermal properties for processing and treatments, time stability properties under wor-
king conditions in any application), but also the crite-
ria of reducing fire risk as this characteristic becomes of major interest in particular and general industrial
applications [1-54, 13, 22].
For industrial applications of vegetal oils their
flammability characterisation is of recent interest as
researches were conducted especially for improving
their properties obviously required by the system: viscosity, time-temperature stability etc. The industrial
oleochemicals business is investigating the use of high
oleic vegetal oils in order to act as feedstock for the production of numerous products [7, 14, 21]. These
products not only have the ecological benefit of being
biodegradable and derived from a renewable resource,
but they also have different and enlarged functiona-
lities.
High oleic vegetal oil is being tested and
utilized in the cosmetics business and as a machine
lubricant (e.g., for high temperature engine, transmissions, hydraulics, gears and grease
applications). Independent testing has shown that
these new oils may actually perform better than petroleum-based products in some uses [12, 14, 21].
Longterm projections in dicate that continued
advancement in industrial ap plications research could
result in an even greater volume requirement for high
oleic oils in industrial applications than in edible
applications [7].
Until recently, manufacturers have not had
much choice. Synthetic alternatives to mineral oils,
such as polyglycols and polyol esters, have been priced out of reach for most manufacturers. Those
with high-pressure and other extreme applications
requiring a fire-resistant hydraulic fluid have had to “bite the bullet” – paying up to six times more for
synthetic hydraulic oils than they used to pay for
petroleum-based products (fig. 3) [14].
To answer this need, many industrial oil produ-
cers have began to formulate efficient hydraulic fluids based on vegetal oils. Because vegetal oil is a
naturally occurring ester, it is biodegradable. It also
exhibits good lubricity, on par with synthetic polyol ester fluids. In addition, vegetal oil is a relatively
inexpensive base stock [14, 17].

These vegetal oils have traditionally exhibited
low oxidative stability – a critical shortcoming, which
prevented their widespread use [10]. However, resear-ches and tests are continued, working with additive
packages and using selected base stocks, and creating
fire-resistant fluids [14, 21]. For instance, Cosmolubric B-230 [14] is a canola
1 oil-based and
uses additive technology to successfully perform like
polyol esters. It contains viscosity index modifiers, rust and oxidation inhibitors, extreme pressure (EP)
additives, copper passivators and defoamers. These
additives have improved the oxidation stability of vegetal oils, so that they can equal the desired
characteristics of synthetic polyol esters.
02468Mineral oil Invert emulsion Water glycol Canola oil Synthetic polyol ester Phosphate ester
Fig. 3. Cost comparison of hydraulic
fluids base stocks [14].

Table 1. Cost comparison of hydraulic fluid
base stocks (adapted from [14]).
Canola
oil Synthetic
polyol Mineral
polyol
ISO viscosity grade 68 68 68
Viscosity [cSt]:
at 100°C
14.3
12.5
8.3
at 40°C 75.1 68.3 74.0
Viscosity index 214 214 90…100
Acid number 0.9 3.0 0.8
Flash point, °C 257 312 196
Fire point, °C 321 615 218
Pour point, °C -18 -23 -15
Specific gravity 0.92 0.92 0.88

1 Rapeseed ( Brassica napus ), also known as rape, oilseed rape,
rapa, rapaseed and (in the case of one particular group of
cultivators) canola, is a bright yellow flowering member of the
family Brassicaceae (mustard or cabbage family). The name
derives from the Latin for turnip, rāpum or rāpa, and is first
recorded in English at th e end of the 14th century.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
126
Organizations such as Occupational Safety and
Health Association (OSHA), National Fire Protection Association (NFPA) and so me specialists classify
flammable liquids according to their flashpoint [1, 4,
11, 22]. A flashpoint within the operating temperature
range of the system is obviously undesirable as any
leak would create an immediat e fire hazard [1, 4, 14].
Thus, the aim of the paper is to give a qualifica-
tion of this grade of rapeseed oil (the grade obtained after dewaxing process of the oil) concerning the
flammability on hot surfaces.
In 2000 Koseki, Natsume and Iwata reported
that the flash points of vegetal oils are above 300°C,
which are considerably higher than those of fuel oils
with flash points of 100°C and lubricating oils with flash points of 160…300°C, vegetal oils being
considered relatively safe r than hydrocarbon oils.
However, it was found that the burning rate, radiant heat, and flame height of vegetable oils are higher
than those of C-fuel oil or some of lubricating oils.
This means that once a fire occurs, the fire
propagation danger of vegetal oils is higher than C-
fuel oil or some of lubricating oils [13].

2. TESTING METHODOLOGY

The standard EN ISO 20823:2003 “Petroleum and related products. Determination of the
flammability characteristics of fluids in contact with
hot surfaces. Manifold ignition test” was adopted in Romania in 2004, by the endorsement method and it
gives a testing method for determining the relative
flammability of a fluid when it contacts a hot metallic surface having a fixed temperature. The method also
allows establishing the ignition temperature of the
studied fluid by increasing the manifold temperature in steps.
The test results are quantified in only three
possible results: I(T) when the fluid flashes or burns
on the tube, but does not continue to burn when
collected in the tray below, I(D) when the fluid
flashes or burns on the tube and continues to do so
when collected in the tray below and N when the
fluid does not flash or burn at any time. The procedure was well established in order to obtain
repeatability, a much desired characteristic of test
results, but hard to obtain for test involving fire or flammability characteristics.
The equipment used in LubriTEST Laboratory
at University “Dunarea de Jos” of Galati has this plat-form with three thermocouples as ISO standard
recommends (position 7 in fig. 4) [5], but a better
accuracy was obtained with a thermocouple attached to the manifold surface and protected by a small case
made of the same steel as the manifold, welded as the
thin bar required by the standard. Figure 5 presents the display of the PC included in the testing
equipment in order to preserve the design
requirements as established in the logical chart in figure 6. Points 1 and 2 (fig. 5) are confirmed by Romanian Bureau of Legal Metrology (BRML) to
fulfil the requirements of SR EN ISO 2003:84,
meaning reaching a temperature of 700 ±5șC, point 3
having a tolerance greater than ±5șC, but not reaching
±6.0șC); this is the reason why point 3 is used only
for research purpose and for protecting the manifold
not to have a thermally non-loaded zone. All results
presented here are obtained for points 1 and 2 (fig. 5
and table 2).

Fig. 4. Frammability test Equipment: 1-dispenser
monitoring system, 2-ventilated enclosure, 3-2D
robotic arm, 4-fluid reservoir, 5-high temperature
steel sheet box, 6-hot manifo ld (with electric heater),
7-the thermocouples’ platform, 8-automatization
system, 9-video fast camera.

Fig. 5. View of the commanding display of the
equipment computer.

The samples of rapeseed oil (obtained after a
dewaxing process) were tested under the standard conditions (10 ml ± 1ml of tested fluid dropped on the
hot manifold in 50 s±10 s, initial oil temperature:
20…25șC, ambient temperature: 20…22șC, air relative humidity: 58±12%).
Table 2 presents the test results, in a
chronological order, last column having some authors’ remarks about the fluid behaviour when
dropping on the hot surface being maintained at
different temperatures.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
127
C TT T TTrequestedC C C
m0533 2 1±=++=C T Tcerut m05±>
C T Trequested m05±>

Fig. 6. Logical chart of the testing equipment [8, 9] as designed by professor Lorena Deleanu and put into
practice by ICTCM Bucharest, Dolsat SA an d University “Dunarea de Jos” of Galati.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
128

3. RESULTS AND DISCUSSION

Oil samples were obtained from ULVEX SA
Țăndărei, Romania and all tested samples were of rape-
seed oil after a dewaxing process, from the same charge.
Taking into account form er papers and tests [8,
9], table 2 presents the behaviour of this vegetal oil
grade, this one being separated into three classes,
depending on the temperature range and the fluid behaviour:
1. a temperature range for which there are
obtained repeatedly the same results when testing the fluid on hot manifold (200…551șC);
2. a temperature range for which the test results
are randomly different (in one test the fluid does not burn, but in the following one it is burning and so
on): 551…557șC;
3. The temperature range for which the fluid
burns, receiving one of the two qualifications,
depending on the burning process:
θ > 560șC.
Analysing the recorded films of the tests the
authors noticed the followings:
• when tested at the highest temperature at which
the fluid does not burn, there was noticed white, foggy vapour due to the evaporation of some
components of the oil, but liquid drops of fluid are still visiblely flowing on the hot manifold;
• there is a tendency of fluid to flash and/or burn
on the tube and continues to do so when collected
in the tray below (meaning the qualification I(D),
as coded in the ISO stan dard), characterising the
temperature range closely above 551șC, that is 560…570șC and not the highest range tempera-
ture tested in the laboratory (600șC);
• tested at 570…600șC, the oil could get the quali-
fication I(T), that is when the fluid flashes or
burns on the tube but does not continue to burn when collected in the tray below.
Even if the dropping process was regulated
before heating the manifold, meaning the oil volume
to flow in small drops, with a quite constant rate
during 40…60 seconds, as imposed by the test procedure in the ISO standard, the burning process
was intermittent for almost all tests as one may notice
from analyzing the photos presented in figures 7 to 10. This could be explained by the presence of many
chemical constituents in this vegetal oil, and further
study will be done for trying to explain this process. Taking into account th e results, the temperature
at which the tested oil does not burn anyway (551șC)
is similar to some previously tested additivated mineral oils for transmissions, including T90
(Rompetrol); this oil had obtained the qualification N
for 545șC, but from 550șC it burns getting an I(D) qualification. Tests were re peated 6 times for each of
these temperatures.
As temperature allowances are
±5șC, any test between this two values (545 and
550șC) are irrelevant, especially because tests
between these temperatures do not have repeatability
for T90 (Rompetrol). The same conclusion could be
underlined for the temper ature range 552…562șC for
the dewaxed rapeseed oil.

Table 2. Results of testing dewaxed ra peseed oil flammability on hot surface.
Test
no. Temperature
of the
manifold
surface [șC] Dropping
time
[s]
Fluid qualification
Comments
1 200 57 N
2 250 45 N
3 300 49 N
4 350 40 N
5 400 56 N
6 450 45 N
7 500 43 N; very fine traces of white vapour (vis ible only on the film and under careful
observation of the manifold surface; also there are visible fluid drops sliding
along the manifold and falling on the tray below.
8 551 39 N; (dropping time is 1 second shorter than the interval recommended by ISO
standard procedure); white vapour, very vi sible, but with variable intensity of
generation: there are also visible fluid drops sliding along the manifold and
falling on the tray below (fig. 7).
9 600 42 I(T); fluid burns, the flames being continuous , but having variable height in time
10 574.6 38 I(D); (dropping time is 2 second shorter th an the limit value recommended by
ISO standard procedure); test was repeat ed after tuning the dispenser (fig. 9).
11 575 45 I(D); the fluid burns intermittently.
12 577.2 I(D); the fluid burns intermittently (fig. 10)
13 562 59 I(T) (fig. 8).
Note: I(T) when the fluid flashes or burns on the tube but does not continue to burn when coll ected in the tray below, I(D) when the fluid
flashes or burns on the tube and continues to do so when collected in the tray below and N when the fluid does not flash or burn at any time.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
129

6th second 14th second 43th second
Fig. 7. The rapeseed oil tested on the ma nifold having the temperature of 551șC.

2nd second (first drop on
manifold, visible white fume, but
the drop does not burn yet) 11th second (the oil does not burn
yet, but there is visible fume, but
oil is changing its chemical
structure and reaction substances
remain on the manifold as dark
and non-uniform deposits). 20th second (this drop is burning
on the tube and part of it continues
to burn when falling, but does not
reach the tray in burning).

22nd second (detail of the burning
oil on the hot manifold). 58th second (the oil burns in the
tray). 59th second (last drop is
extinguishing on the manifold).
Fig. 8. The rapeseed oil tested on the manifo ld surface heated at the temperature of 562.0șC.

4. CONCLUSION

Prediction or diagnosis is connected by the
future evolution of various processes occurring inside the complex technical systems with a view to
optimizing their relevant parameters. Diagnosis
implies a work for putting into a structure the cumulated knowledge. This structure must be based
on the systems theory.
The after-dewaxing rapeseed oil could be
recommended as industrial fluid, not only as bases for
lubricant formula, but also as industrial fluid for cutting processes or heat treatment, especially
because it could be used in some of these applications
as emulsions oil-in-water or water-in-oil. Of course,
the first type could be less expensive, but design and maintenance engineers have to pay attention to how
the presence of water would affect machine elements
and durability of the entire system, even if these solutions are environmentally friendly.
The after-dewaxing rapeseed oil is only a
product obtained after a necessary step in refining vegetal oils, but further processes of modifying this
oil could give better results as concerning the
flammability on hot surfaces or/and other desired properties.
Studying how the oil is manifesting on hot
surfaces could offer solutions for fire sensors and fire
suppression in industrial, transport fields, but also for
those used in public food service, evaluating better the fire risks in these domains of activity.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
130

1st second (first oil drop under the
nozzle of dispensing device). 2nd second (first oil drop reached
the hot manifold surface). 4th second

6th second 8th second
10th second

11th second 12th second
13th second

15th second 17th second 19th second

Fig. 9. The rapeseed oil tested on the surface manifold temperature of 574.6șC.
Note. All images were extracted with the help of a specialized soft
in order to observe the time recorded on the PC display.

THE ANNALS OF UNIVERSITY “DUN ĂREA DE JOS“ OF GALATI
FASCICLE VIII, 2009 (XV), ISSN 1221-4590
TRIBOLOGY
131

2nd second(first drop on manifold) 3rd second 4th second

5th second 6th second (second drop on
manifold). 7th second
Fig. 10. The rapeseed oil tested on the manifold surface heated at 577.2șC
(snapshots are chronologically extracted).

REFERENCES

1. ** Approval Standard for Flam mability Classification of
Industrial Fluids (Class 6930), Factory Mutual Global, January
2002. 2. ** Council Directive 92/104/EEC of 3.12.1992 on the mini-
mum requirements for improving the safety and health protection
of workers in surface and u nderground mineral-extracting
industries (twelfth individual Directive within the meaning of
Article 16 (1) of Directive 89/391/EEC) (OJ L 404, 31.12.1992),
Amended by: Directive 2007/30/EC of the European Parliament
and of the Council of 20.06.2007, L 165 21 27.6.2007
3. ** Directive 94/9/EC of the European Parliament and the
Council of 23.03.1994, on the approximation of the laws of the Member States concerning equipment and protective systems
intended for use in potentially explosive atmospheres, (OJ L100,
19.4.1994, 1), amended by Regulation (EC) No 1882/2003 of the European Parliament and of the Council of 29.09.2003, OJ L284 1
31.10.2003, Corrected by Corrigendum, OJ L21, 26.1.2000, 42
(94/9/EC), Corrigendum, OJ L304, 5.12.2000, 19 (94/9/EC). 4. ** HSE Approved specifications for fire resistance and
hygiene of hydraulic fluids for use in machinery and equipment in
mines, (M) File L11.6/3, (1999). 5. ** ISO/TC 28N 2139, 2001, Results of voting ISO/CD
20823 Petroleum and related products. Determination of the
flammability characteristics of fluids in contact with hot surfaces. Manifold ignition test. 6. .**
Food and Agriculture Organization of the United Nations,
FAO Statistics Database, http://faost at.fao.org/, available on-line at
the address: http://faostat.f ao.org/site/339/default.aspx
7. Butzen S., Schnebly S., 2009, High Oleic Soybean, on-line:
http://www.pioneer.com/web/s ite/portal/menuitem.666b80f644978
322a0030d05d10093a0/#indus 8. Deleanu L. et al., 2007, Research Report for grant CEEX-M4-
452 “Adoption and Implementation of Test Methods for Lubricant
Con-formity Assessment” supported by National Authority for Scientific Research, Minister of Education and Research Romania.
9. Deleanu L. et al., 2007, Flammability Test Data in Risk Assess-
ment, 10th International Conference on Tribology , Bucharest,
Romania, paper RO-061, pp 2.2-6. 10. Fox N.J., Stachowiak G.W., 2007, Vegetable oil-based
Lubricants. A review of oxidation, Tribology International , 40, pp.
1035-1046.
11. Jagger
S.F. Nicol, A., Sawyer J., Thyer A.M., 2004, The
incorporation of fire test data in a risk-based assessment of hydraulic fluid fire resistance, INTERFLAME , p.
569-576.
12. Karheinz H., 2000, Fats and oils as oleochemical raw
materials, Pure Appl. Chem. , vol. 72, no 7, pp. 1255-1264.
13. Koseki H., Natsume Y., Iwata Y., Evaluation of the Burning
Characteristics of Vegetable Oils in Comparison with Fuel and
Lubricating Oils, Journal of Fire Sciences , vol. 19,
January/February 2001, pp 31-44.
14. Noblit T., 2005, Biodegradable Hydraulic Fluids Prove Bene-
ficial – Fire Resistance a Plus, Machinery Lubrication Magazine ,
March 2005
15. Qingye Gong Q., He W., Weimin Liu W., 2003, The
tribological behavior of thiophosphates as additives inrapeseed oil,
Tribology International , 36, pp. 733-738.
16. Shunmugam V., 2009, Biofuels—Breaking the Myth of
‘Indestructible Energy’?, Journal of Applied Economic Research,
vol. 3, no. 2, pp. 173-189.
17. Schneider M., Smith P., 2002., Plant Oil in Total Loss &
Potentisl Loss Applications, Finall Report, Government Industry Forum on Non-food Uses of Crops (GIFNFG 7/7), 16 May.
18. Hayes, K.F. Skerlos S.J., 2006, Design of Novel Petroleum
Free Metalworking Fluids, R831457, US. 19. Toy, N. Nenmeni, V.l., Bai X., Disimile P.J. , 2004, Surface
ignition on a heated horizontal flat plat, 4
th Intern. Aircraft & Cabin
Safety Research Conerence.
20. Yuan L., 2006, Ignition of hydraulic fluid sprays by open
flame and hot surfaces, J. of Loss Prevention in Process Industry ,
vol.19 (4), pp. 353-361 .
21. Zeng X., Wu H., Yi H., Ren T. , 2007, Tribological behavior
of three novel triazine derivatives as additives in rapeseed oil,
Wear , 262, pp. 718-726.
22. Zinc M.D., 2000, Fire Resistant Hydraulic Fluids: Shifting
Definitions and Standards, Proc. of 48th National Conf. on Fluid
Power , paper 105-8.3.