Lubricants
What is it?
The HFRR is a reciprocating tribometer, originally designed for analysing the lubricity of diesel fuels. It is also used for screening the lubrication performance of engine oils and additives which are active in boundary lubrication.
Why do we use it?The HFRR is a quick and easy screening method for determining friction and wear profiles for fuels and lubricants. In the case of diesel fuels it provides an absolute value in terms of wear scar and for lubricants it gives an indication of performance before the lubricant is further investigated using other methods, if required.
How does it work?
A polished steel ball and disc are placed in their respective holders, and are arranged on the HFRR unit. They are then put under load. The upper ball holder is moved in a reciprocating motion across the stationary steel disc.
The HFRR can be run at various temperatures and be programmed to suit the particular application of the fuel or oil being tested. A number of standard test methods have also been developed, such as ASTM D6079, ASTM D7688, CEC F-06-A, ISO 12156, EN 590, JPI-5S-50, and IP 450.
The diameter of the wear scar on the ball is measured using a microscope. The displaced volume can also be determined with use of the 3D image optical microscope.
The HFRR Machine:
Typical Test Conditions:
Parameter : Value
- Frequency : 10 to 200 Hz
- Stroke Length : 20 µm to 2.0 mm
- Temperature : Ambient to 150°C
- Load : 0 to 10 N
3D Representation of Wear Scar:
Profilometer Analysis of Wear Scar: