Test Method
A 2-mL test specimen of fuel is placed in the test reservoir and maintained at 25 or 60°C. When the temperature has stabilized, a vibrator arm holding a non-rotating steel ball and loaded with a 200-g mass is lowered until it contacts a test disk completely submerged in the fuel. The ball is caused to rub against the disk with a 1-mm stroke at a frequency of 50 Hz for 75 min. The ball is removed from the vibrator arm and cleaned. The dimensions of the major and minor axes of the wear scar are measured under magnification and recorded.

Features and Benefits
• ASTM D6079; ISO 12156
• Capable of engaging a steel ball loaded against
a stationary plate with an applied load and
oscillating at a fixed frequency and stroke length
while the contact interface is fully immersed in a
fluid reservoir.
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Click on the image to view a larger photo of the instrument.

K93450 High-Frequency Reciprocating Rig (HFRR)
The two-station Fuel Lubricity Wear Test Machine incorporates two test positions with heater pads and mounting arrangements for fuel lubricity test specimens. Load is applied manually by means of dead weights directly to the fixed ball specimen carrier by means of a loading yoke. Machine controls are limited to speed control of the drive motor to give the required frequency, temperature control of the specimen bath and test duration. Test data is limited to post test wear scar measurement only and no facilities are provided for friction force measurement.
The electro-mechanical drive is used to achieve a wide range of frequencies, and the 1 mm stroke is generated with a cam. This ensures that the amplitude remains constant as friction forces vary in the contact. The ball specimen is mounted in a holder connected to the horizontal oscillating shaft. The shaft is double ended and two tests can be run at the same time. The holder is hinged to ensure that the line of action of the oscillator remains in the horizontal plane of contact. This also means that loads can be applied directly to the contact without loading the oscillator shaft. A simple yoke locates on the oscillating shaft and load is applied by calibrated weights.
The plate specimen is located in a bath that both seals and clamps the specimen. Beneath the bath is a block that is heated by an electrical resistance element and the temperature is controlled by a thermocouple closely located beside the specimen. Each heater block is mounted on a stiff fabricated support. A clear acrylic cover is provided to house the test heads. Operation of the machine is straightforward. The machine is equipped with two digital programmable controllers for temperature. Temperature setpoint can therefore be set independently for each station. In addition, there is a digital programmable frequency controller and test timer.
The controllers are pre-set when the machine leaves the factory to the operating conditions required of the test methods. Once enabled, the machine heats each of the baths to a set point of 60°C. Once this temperature is reached the motor is switched on automatically to run at 50Hz. The test timer is preset for the duration of 75 minutes, which commences once the motor starts. At the end of the test the machine automatically switches off.

Specifications
Model: K93450
Test specifications: ASTM D6079; ISO 12156
Contact Geometry: Ball on Plate
Ball Specimen: 6 or 10 mm diameter
Load: 1.95 to 10.00 N (± 0.01 N)
Stroke: 1 mm (± 0.02 mm)
Frequency: 2.5 to 50 Hz (± 1 Hz)
Fluid Volume: 2 mL (± 0.2 mL)
Test Temperature: Ambient to 100°C
Heating Power: 250W at each station
Temperature Sensor: K-type thermocouple
Test Duration: 75 min (± 0.1 min)
Bath Surface Area: 6 cm2

Electrical Requirements
115V 50/60Hz, Single Phase
230V 50/60Hz, Single Phase