Current research projects

Image Micro heat exchangers in refrigeration
Image Electrochemical decontamination of electrically conducting surfaces „EDeKo II“
Image Preformance measurements of heat exchangers
Image Air-flow test rig for fan characteristic measurement
Image Performance tests of refrigerant compressors
Image Thermostatic Expansion Valves
Image Optimizing HVAC operation with machine learning
Image IO-Scan - Integral measuring optical scanning method
Image Certifiable connection types in cryogenics
Image Test procedures for electrical components
Image Cool Up
Image Measurement of insulated packaging
Image Hybrid- Fluid for CO2-Sublimation Cycle
Image Service offer for Leak Detection and Tightness Test
Image All-in-one device for freeze-drying and production of biomaterial
Image Ice Slurry Generation

You are here:   /  Home


Tribological investigations of oil-refrigerant-material-systems

Dr.-Ing. Margrit Junk

+49-351-4081-5419

Modified Almen-Wieland wear testing machine

The modified Almen-Wieland wear testing machine is used for the determination of the tribological properties of oil-refrigerant-bearing-systems under mixed friction conditions. The interaction of lubricants, additives, refrigerants and materials is tested. On the basis of these investigations refrigeration oils and materials could be preselected, but the tests can not substitute field test with refrigeration machines.

Principle

Two half bearings are pressed hydraulically against a test pin rotating horizontally in the lubricant.

The extreme pressure failure, i. e. the load bearing capacity of oil, is determined by increasing continuously or stepwise the test load until seizure of pin and bearing occurs and the pin breaks. The coefficient of friction and the wear are determined with constant (low) load applied during a prescribed test time.

Specialties

  • Hermetic test cell, which allows testing with refrigerant pressures up to 10 bar.
  • Thermostated test cell for a defined lubricant temperature.
  • Continuous record of fest force, turning moment, pressure of refrigerant, temperature and wear.
  • Use of both Almen-Wieland and half bearings with Falex geometry (dimensions of the V-block than the original Falex bearings according to ASTM D 3233).
  • Adaption of the tribological system by choosing materials of test pins and half bearings.

Our services

  • Evaluation of lubricant-refrigerant-material-systems by load bearing capacity of lubricant (extreme pressure failure load), coefficient of friction, wear, changes of lubricant
  • Evaluation of tribological systems after changing lubricants, refrigerants or bearing materials in order to minimize expensive field tests
  • Failure analysis

 


Your Request

Further Projects

Image

Software for technical building equipment

Design cooling load and energetic annual simulation (VDI 2078, VDI 6007, VDI 6020)

Image

Measurements on ceiling mounted cooling systems

Comparative performance measurement

Image

Micro fluidic expansion valve

for increasing of the efficiency of small and compact cooling units

Image

Solar Cooling

Solar Cooling with Photovoltaic

Image

Hydrogen and methane testing field at the ILK

Simultaneously pressures up to 1,000 bar, temperatures down to –253°C