An Overview Of Pin-on-disk Tribometers

By Author: Vishal Khosla
Total Articles: 19
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Pin-on-Disk Tribometer measures coefficient of friction and wear rates of coatings with or without lubrication. The instrument features linear reciprocating movement as well as rotating, integrated stylus profilometer and a high resolution frictionless force sensor design.

All manufacturers face the issue of friction and wear in moving machine parts. It is important for them to get quantitative data derived at varying temperature and humidity, and in the presence of lubricants. They need to procure Pin-on-Disk Tribometer (TRB) that displays features such as

* Accurate testing in liquids and controlled humidity
* Precisely calibrated friction and wear measurements
* Automatic switch-off (track length / friction coefficient)
* Stable contact point and no parasitic friction
* Testing compatible with DIN 50324 and ASTM
* Software package for PC-controlled instrument control and data acquisition
* Featuring real-time graphical data display, friction and wear coefficients

Pin-on-disk Tribometer deploys a simple load arm with a tangential force sensor for curtailing errors ...
... due to arm compliance. However, if you intend to use it at elevated temperature, a different configuration would be required for avoiding local heating and dilation within the sensor. For this objective a load arm with two LVDT (Linear Voltage Differential Transformer) sensors is used for measuring the tangential force independently. Thereafter an average value is computed either as a straight or an integrated signal.

For controlled lubricant studies, the tribometer is a bit modified. The system ensures homogeneous heating of the sample. A thermocouple is placed for accurately monitoring the sample temperature. A regulator controls heater as well as thermocouple.

Measuring the mechanical properties of coated optical fibers is hard owing to the curved geometry of the surface and positioning related problems of the pointed tip. Again, the structure of the tribometer is altered a bit to suit the application.

The instrument measures coefficient of friction and wear rates of coatings with or without lubrication. It features linear reciprocating movement as well as rotating, a high resolution frictionless force sensor design and integrated stylus profilometer.

Wear coefficients for the samples are calculated from the volume of material lost during the test. It enables one to study friction and wear behavior of almost every solid material combination. Testing can be done with or without the lubricant.

A top-of-the-line pin-on-disk tribometer offers precise wear and friction testing using ISO and ASTM compliant linear and rotative modes. It would provide access to a range of rotational speeds from 0.01 to 2000rpm. High resolution means that recording of data can be accurately done at specified interval of time or position. Integrated self-tuning system in the tribometer ensures that speed remains calibrated through time.

A quality tribometer would provide you with several testing options for closely matching real environment conditions. It would be supplied with an acrylic enclosure and the valves that support controlled environment. You may also get an optional humidifier and dehumidifier module allowing you to exercise control of the humidity levels. A high temperature pin on disk tribometer can handle high temperature running up to several hundred degree Celsius.

For measuring wear track volume, an optical profiler integrated on Tribometer platform quantifies wear loss in the sample. The profiler can also be used for measuring surface topography including roughness. Instruments also have zoom-in ability to record the sample surface for playback review.

Author of this article is associated with Rtec Instruments that deals in equipment like Tribometer, Surface Profiler, Indentation and Scratch Tester, 3D Profilometer and Stress Tester.