Standard Test Equipment
Pendulum slip resistance test
The pendulum slip resistance meter measures surface friction using an energy loss principle as used in the Charpy Impact test. As the pendulum strikes a surface energy is lost, which can be translated into a friction coefficient. On the end of the pendulum is a rubber slider, which is spring mounted so that a constant normal force is present through the entire contact. The rig uses two different types of rubber pad; Four-s and TRL. The harder Four-s type rubber represents the heel of the average shoe and the TRL (softer pad) represents the heel of a foot.
| BS EN 13036-4:2003 | Method for measurement of slip/skid resistance of a surface. |
| AS/NZS 4586:2004 | Slip resistance classification of new pedestrian surface materials |
| BS 7976-1:2002 | Pendulum Testers: Part 1 - Specification |
| BS ISO 48:2007 | Rubber, vulcanized or thermoplastic. Determination of hardness. |
Plint TE77 reciprocating friction rig
The TE77 variable speed reciprocating machine is used to assess the dynamic wear and friction performance of lubricants, fuels, materials and surface coatings. The contact consists of a fixed plate and reciprocating pin. Friction force output is automatically logged using the TE77SLIM Data Acquisition System.
| Shape of contact: | Nominally point, line, area, piston ring/cylinder |
| Normal Load: | 5 to 250N |
| Temperature: | Room to 250°C |
| Frequency: | 0.1 to 50Hz |
| Amplitude: | 1 to 15mm in 8 steps or 0.5 to 5mm in 8 steps |
| Lubrication Conditions: | Lubricated/Dry |
| Method of Lubrication: | Immersed, thin layer, drip fed |
| ASTM G133 | Standard Test Method for Linearly Reciprocating Ball-on-Flat Sliding Wear |
High Frequency Reciprocating Wear Tester
Wear testing can be a long process, especially if specimens are lubricated and lightly loaded. The use of high frequency sliding accellerates the test. This kind of test can proves useful for the screening of materials, lubricants, and surface coatings. An electrical oscillator is powered by a sine wave signal generator. The oscillator drives the slider across a stationary counter face. The slider is dead weight loaded.The friction force (with sinusoidal variation) can be measured on an attached force transducer.
| Stroke Length: | 100um - 5mm (depending on load and frequency) |
| Max. Frequency: | 200Hz (low load) |
| Load: | <50N (at low frequency) |
| Typical Contact Pressures: | 0.1 - 1GPa |
| Test Conditions: | Elevated temperature and corrosive/toxic environment testing possible |
| Specimen Dimensions: | Typically flat specimens 1cm x 1cm x 5mm against 5mm diameter ball |
Biceri universal wear tester
This machine is capable of being used used as a pin-on-disk, block on ring or pin on reciprocating plate rig.These modules and other optional systems allow the rig to test surface fatigue, abrasive wear and adhesive wear under realistic operating conditions, including dry, lubricated and three-body and at elevated temperatures. The testing of lubricants such as greases and oils can be accomplished using standard contacting material pairs. A corrosion resistant feed system is available for testing in salt water and acids.
| Shape of Contact: | Nominally point, line, area |
| Disc Diameter: | 30-150mm |
| Speed Range: | 20-500rpm |
| Max. Fluid Temperature: | 250°C |
| Lubrication Conditions: | Lubricated/Dry |
| Method of Lubrication: | Immersed, thin layer, drip fed |
| ASTM G99 | Standard Test Method for Wear Testing with a Pin-on-Disk Apparatus |
| ASTM G133 | Standard Test Method for Linearly Reciprocating Ball-on-Flat Sliding Wear |
Pin on Disk
This is a standard pin on disk wear tester that is capable or running continuously for long periods of time resulting in large sliding distances. A pin of one material is loaded against a sliding flat surface or rotating cylinder. The weight loss from either the pin or the counterface is measured. Wear is usually expressed as worn volume per unit load per unit sliding distance.
| ASTM G99 | Standard Test Method for Wear Testing with a Pin-on-Disk Apparatus |
Lissajoux Multi-Directional Slider
The test machine consists of a fixed specimen attached to a floating bed. This is powered by two individually controllable pulsating motors. The fixed specimen is loaded from above. It is possible to create a large number of motion configurations.
Twin Disk Suros Machine
The test machine consists of two rollers which are driven by independent electric motors. The disks are loaded together hydraulically. The motors are controlled such that small levels of sliding can be achieved. Repeated stress cycles can cause the initiation of fatigue cracks, or micro-slip within the contact resulting in wear taking place. The testing of full size components can often be difficult and expensive.
| Max. Rolling Speed: | 400rpm |
| Max. Contact Pressure: | 1500MPa |
| Slide Roll Ratios: | 0.1% to 20% |
Lubricant Film Thickness Analysis and Measurement
We have a great deal of experience with regards to film thickness measurement. The majority of the work carried out uses non-destructive ultrasonic techniques that are capable of measuring oil films as thin as 0.01 microns. It is possible to measure films in numerous situations, from dedicated test rigs looking at EHL in soft bearings and combustion engines to in-situ measurements of machinery and testing equipment. Our set up consists of an ultrasonic pulser, a digitiser, and a PC. A transducer is coupled (either with glue or in a fluid bath) to the back face of a bearing and functions as both a transmitter and receiver of the ultrasonic signals.
| Measuring Range: | Three ranges depending on frequency and signal processing >100 µm, 10 µm – 100 µm, 0.05 µm – 20 µm |
| Mapping Resolution: | 100 – 500 µm |
| Sensor Dimensions: | Depends on application typically ~diameter 10 mm |
| Measurement Response Time: | >0.1ms |
EHL Bearing Rig
This apparatus is used to generate a single EHD lubricated contact. A rubber ball is supported on rollers and hydraulically loaded onto the underside of a steel disc. The ball is rotated at constant speed by an electric motor through a gear box and quill shaft. The Perspex disc is held stationary such that the ball is completely sliding against the underside of the disc. The ball-disc contact is flooded with a mineral oil, which is entrained into the contact to form an EHD film. A focused transducer is mounted above the contact in a water bath. The transducer is positioned directly above the contact region and at a distance such that the wave is focused on the ball-disc interface.
| Load: | 0-60N |
| Max. Hertzian Pressure: | 0 - 0.8 GPa (steel on glass) |
| Rolling Speed: | 0 - 2500 rpm (+/- 1%) |
| Slide/Roll Ratio: | - 0.08 ± 0.1 |
| Bulk Oil Temperature | 20 - 200 0C |
Low Speed Friction Rig
Friction measurements are carried out on this Bowden & Leben type apparatus. It consists of a top specimen which is loaded against a counterface driven by a variable speed electric motor. It is possible to measure both static and kinetic coefficients of friction at low sliding speeds. The frictional force between the specimen and the counterface causes the loading arm to push against a force transducer. Data is captured via an oscilloscope using simple PC software. Both static and dynamic friction coefficients can be measured.
| Max. Tractional Force: | 140N |
| Max. Normal Load: | 800N |
| Contact Pressures: | 1-15MPa |
| Temperature: | Up to 120 degrees C |
| Speed: | 0.5mm/s to 5mm/s |