Al Farabi University College كلية الفارابي الجامعة
Scientific Report
Name: Aliaa Abbas Sabbar االسم علياء عباس صبار غالي
Department: Civil Engineering الهندسة المدنية:القسم
Stage: 4th stage صباحي- الرابعة:المرحلة
Subject: Communication
Experiment: Standard Test Method for Saybolt-fural viscosity
ASTM D88-99
Experiment No: 1
Saybolt-fural viscosity test
Introduction
Saybolt Furol viscosity - the efflux time in seconds required for 60 milliliters of
a petroleum product to flow through the calibrated orifice of a Saybolt
Purol viscometer, under carefully controlled temperature, as prescribed by test
method ASTM D 88. The method differs from Saybolt Universal viscosity only in
that the viscometer has a larger orifice to facilitate testing of very viscous oils, such
as fuel oil (the word "Purol" is a contraction of "fuel and road oils") [1].
There are two types: 1-saybolt universal viscosity: It is the corrected efflux time in
seconds of 60 mL of sample flowing through a calibrated universal orifice under
specified condition. The viscosity value is reported in Saybolt universal seconds
abbreviated SUS at a specified temperature. It is determined using an orifice of (1.76
±0.015) mm in diameter used for lubricants and distillates with efflux time greater
than 32 sec. and less than 1000 sec. 2-Saybolt furol viscosity: It is s the corrected
efflux time in seconds of 60 mL of sample flowing through a calibrated orifice under
gravity at specified temperature. The viscosity value is reported in Saybolt Furol
seconds, abbreviated SFS, at a specified temperature [2]. This is determined using
an orifice of (3.15 ±0.02) mm in diameter used when "SUS" value is greater than
1000 sec. The viscosity value is reported in-Saybolt Furol seconds, abbreviated SFS,
at a specified temperature. The "SFS" is approximately one tenth the "SUS". Furol:
refers to "Fuel and road oils."
In this report, a test approach covers the experimental procedures to determine the
Saybolt universal or saybolt Furol viscosities of petroleum products at specified
temperatures between 21 and 99°C (70 and 210°F). It is recommended that viscosity
indexes be calculated from kinematic rather than Saybolt viscosities.
Objective:
To determine saybolt viscosity of petroleum products at specified temperature (21-
99) °C.
Theory
Here a specified volume of Asphalt Cement is placed in a standard tube closed with
a cork stopper. Since the temperature of Viscosity determination for the Asphalt
Cement is often above 100°C, oil is used as a medium for the constant temperature
bath of viscometer. After the asphalt reaches a specified temperature the stopper is
withdrawn and the time in seconds is measured for the flow of 60mL of the material
through the Furol orifice [3].
Apparatus
1. saybolt viscosity test assembly (water or oil bath, electrical heater, sample
container with orifice and stopper, mixer).
2. Receiving flask.
3. Thermometer.
4. stop watch.
5. Viscosity thermometer.
6. Filter funnel
7. Withdrawal tube
Procedures:
1. Clean viscometer and receiving flask with appropriate solvent.
2. Place the receiving flask below the bottom of the viscometer.
3. Fill the bath to with water for test temperature less than 98 °C and oil for
higher test temperature. Place the sample in the viscometer container and
insert a cork stopper at the bottom of the viscometer.
4. Calibrate the Saybolt Fural viscometer at 40°C using a viscosity standard with
a minefflux time of 90sec. If the efflux time defers from the standard by more
than 0.2%, calculate the correction factor from the equation 1 below:
𝑉
𝐹= 1
𝑡
5. Where, V and t denote Certified Saybolt Fural viscosity of the standard and
Efflux time at 50°C in seconds respectively.
6. Control bath temperature.
7. Snap the cork and start the timer.
8. Stop the timer the instant the bottom of the oil meniscus reaches graduation
mark (60 ml). 8. Record the efflux timer in seconds to the nearest 0.1 sec. This
will be the viscosity.
Results and Calculation
1. Report the time in the seconds to approximately 0.1 sec.
2. To draw the relationship between viscosity and temperature, arranged a table
contains (temperature and efflux) as follows: -
Temperature °C Efflux time (viscosity) in sec
1. 503 sec.
1. 30°C.
2. 409 sec.
2. 35°C.
3. 336 sec
3. 40°C
The viscosity in centistokes can be calculated using this equation:
cSt=0.226 S-195/S for S 32-100
cSt=0.22*S-135/S for S>100
Where:cSt= viscosity in centistokes, S=viscosity in SUS
Calculation Kinematic Viscosity:
1. cst=0.22×S-135/S
=0.22×503-135/503
=110.66 - 0.2683
=110.3917 cSt
2. cst=0.22×S-135/S
=0.22×409-135/409
=89.98 – 0.3300
=89.65 cSt
3. cst=0.22×S-135/S
=0.22×336-135/336
=73.93 – 0.4017
=73.52 cSt
Discussion
1. What is the effect of temperature on viscosity?
-When a liquid heats up, its molecules become excited and begin to move.
The energy of this movement is enough to overcome the forces that bind
the molecules together, for example, when honey is cold it has a high
viscosity and can be difficult to pour. When heated in microwaves, the
viscosity decrease and the honey flows more freely.
2. What is used on the bath media of viscosity test? Why?
-In this method we use the Oil bath, because oil is for higher test
temperature or sometimes using water for less than 98 °C.
3. Set another method to determine the viscosity?
-Calculating the dynamic viscosity using kinematic viscosity (Standard
Test Method for Viscosity of Transparent Liquids) by using Viscometer.
4. What is the viscosity index of lube oil?
- It is the rate of change of viscosity between 2 temperatures. The lower
the Viscosity Index, the more the drop in viscosity as the oil warms up.
The higher the VI value, the less the drop in viscosity as the oil warms up.
Generally, the less it changes, across a range of temperatures, the better.
Reference
[1] Nicholas P. Cheremisinoff, “Polymer Characterization: Laboratory Techniques
and Analysis”, chapter 4, book, 1996.
[2] Tiab, Djebbar; Donaldson, “Petrophysics: Theory and Practice of Measuring
Reservoir Rock and Fluid Transport Properties. Engineering Pro collection” Gulf
Professional Publishing, Erle C, 2012 .
[3] West Virginia division of highway, “ASPHALT: PLANT
TECHNICIAN INSTRUCTION MANUAL”, chapter 3, 2017.
