ASTM D7217 Standard Test Method for Determining Extreme Pressure Properties of Solid Bonded Films Using a High-Frequency, Linear-Oscillation (SRV) Test Machine
8. Preparation of Apparatus
Preparation of SRV I and II Models
8.1 Turn on the test machine and chart recorder or the PC and allow to warm up for 15 min prior to running tests.

8.2 Select the friction data to be presented in the crest peak value position in accordance with the manufacturer's directions.

NOTE 4 - In most cases, this is accomplished by positioning the sliding switch on electronic card NO. 291.35.20E (front side of electronics behind the front panel) and the sliding switch located back on the panel of the control unit.

8.3 Turn the stroke knob to ZERO.

8.4 Switch the stroke adjustment to AUTO position.

8.5 Set the frequency to 20 Hz.

8.6 Set the desired span and calibrate the chart recorder in accordance with the manufacturer's instructions. Select the desired chart speed.

Preparation of SRV III, IV, and V Models
8.7 When using SRV III, SRV IV, and SRV V models, clean and install the specimens as specified under 9.1.1-9.1.3. Turn on the test machine and the PC and allow to warm up for 15 min prior to running tests.

8.8 Create a set point profile in the SRV control software with the following parameters:

NOTE 5 - Depending on the software version, names and availability of the parameters can vary.

8.8.1 Start conditions (thermostatic stabilization):
Temperature: for example, 50 °C +/- 1 K or 80 °C +/- 1 K
Test load: 20 N +/- 1 N
Start delay: 300 s (is displayed by all versions of the SRV software).

8.8.2 Cut-off criteria for friction, if occurs:
Coefficient of friction, f (cut-off value for permanent increase of level): 0.5 during t > 20 s
Coefficient of friction, f (cut-off value for one-off increase of level): 0.55

8.8.3 Test parameters:
Frequency: 20 Hz
Stroke: 2.00 mm
Pre-load: 20 N for 30 s
Test load: running-in under 20 N for 2 min, then steps of 10 N with a duration of 1 min, 3 min, or 6 min until the maximum test load (usually 2000 N) has been reached.
Total test duration:
With 1 min step duration up to 172.5 min;
With 3 min step duration up to 512.5 min;
With 6 min step duration up to 1022.5 min

NOTE 6 - Because a 30 s break-in at 50 N is used, the load increase times will occur on the half minute of even minutes.

8.8.4 Sample rates for result-relevant measurement channels:
Coefficient of friction, f: #32 ms
Stroke: ≤ 2 s
Test load: ≤ 2 s
Frequency: ≤ 2 s
Temperature: ≤ 2 s
After that, apply a load increment of 100 N every 2 min.

NOTE 7 - For SRV V models, it is recommended to do one sampling per period (that is, 20 ms) for coefficient of friction and stroke.