The PCS Instruments ABSSL System (Automated BOCLE System Scuffing Load)
is a fully automatic laboratory instrument for carrying out lubricity testing
of diesel (middle distillate) fuel. It fully conforms to the requirements
of ASTM D-6078 "Standard Test Method for Evaluating Lubricity of Diesel
Fuels by the Scuffing Load Ball-on-Cylinder Lubricity Evaluator (SLBOCLE)"
The standard PCS ABS test equipment can be modified to allow the SL-BOCLE
tests to be carried out. Alternatively, the ABSSL test equipment can be supplied
as new.
As with the standard BOCLE test, the instrument utilises a flooded, ball on cylinder contact geometry. Since the onset of scuffing is characterised by a sudden rise in the friction force between two contacting bodies, a load cell is incorporated into the load arm assembly. This is able to measure the tangential friction force between the rotating disc and stationary ball.
Advantages:
- Microprocessor control of all instrument functions.
- Simple user interface. Instrument functions can be upgraded by downloading new firmware.
- Both the standard ASTM D6078 test sequences (Procedure A and B) pre-loaded into microprocessor controller.
- Automatic control of whole test sequence.
- No operator-induced variability in test results.
- Automatic flow controllers for moist and dry air.
- No operator input needed to set the humidity and flow rate of the conditioned air.
- Optional PC-based control and data logging software.
- Allows alternative test programmes to be downloaded into instrument, and test parameters to be recorded as a permanent record.
- Interchangeable humidity and temperature probes.
- Humidity and temperature measurement does not need to be re-calibrated - simply replace the combined RH and temperature probe with an exchange pre-calibrated unit.
- Single source of supply for both the test rings and test equipment.
Recognised Standard
- ASTM D6078
Standard Test Method for Evaluating Lubricity of Diesel Fuels by the Scuffing Load Ball-on-Cylinder Lubricity Evaluator (SLBOCLE)
http://www.astm.org
In order to determine the scuffing resistance of a fuel, a number of tests are carried out on the same fluid sample tests using a stepwise series of loads. The higher the SL-BOCLE load rating a fuel has, the more resistant it is to scuffing. The ABSSL microprocessor is pre-programmed with the load sequence and will guide the user through the incremental load sequence defined in the ASTM test method. The operator will therefore not have to refer to any additional documentation whilst carrying out the test. Should any changes to the ASTM test procedure occur, the microprocessor can easily be updated.
Alternatively, if a single test load which is considered to represent an acceptable scuffing limit has already been established, then a single load test may be carried out. The stepwise test is defined as procedure A in D6078 and the single load test is defined as procedure B. The ABSSL is capable of carrying out tests to either procedure.
Fully Automated test sequence - The operator simply has to fit cleaned test specimens, add the fuel sample, fit the break in load and press "Start". The break in sequence lasts for 30 seconds, after which the load is automatically raised. The operator then fits the test load and presses the "Continue" button. The test load is automatically lowered, the test runs for 60 seconds and the test load is automatically raised. At the end of the test, the machine will indicate whether the fuel has passed or failed.
ABSSL system and requirements
The table below explains what is supplied with a typical ABSSL system as standard and additional components that are required to run a test that are sold separately.
Standard system
- ABSSL instrument
- Accessories
- Calibration Kit
Items required to operate the ABSSL instrument complying to ASTM D6078 Standard
- Compressed air (to the specification in ASTM D6078)
- Wear Scar Measurement - a metallurgical microscope and measuring device is required to measure the wear scar after a test.
- Test Specimens
