Friction Performance Test Bench for Engines
Task:
Test rigs serve to investigate influences of different construction features of engine component parts on engine friction energy. Single engine parts (valve drive, camshaft, crankshaft drive etc.) are mounted on test piece clamping device and driven by motor. Single parts as well as complete 6-cylinder engine block may be mounted.
Torque is measured by torque measuring shaft. Test piece may be tested from idling speed to driving speed 7,000 r.p.m. Change of speed may be effected either manually with potentiometer or through four preselectable ramps. With automatic operation speed programme may be selected by computer.Computer evaluates and stores speed and torque data.
Driving-engine performance is 47 kW.Test rigs include oil sypply assembly to be switched in when needed. Oil supply assembly supplies test piece with oil of temperatures between 20 and 135°C.
Solution:
Two different friction test rigs were constructed with central control from control board. Main differences between test rigs are driving power and mechanical construction. Whereas mounting plate of first test rig is steplessly variable over 400 mm, the other’s mounting plate is fixed. Accuracy of mounting plate is acc. DIN 876, quality 3. Dimensions are 800 x 600 mm.
Failure signals:
- oil level
- thermal cut-out
- pressure switch
- circulating pump
- oil pump
- oil filter
- pressure switch supply
- pressure switch cooling water
- total failure signal at test rigs
During normal operation all failure signals lead to cut-out of plant.
With digital technique and display following parameters are measured:
- working hour counter
- temperature (circulating pump or test piece feed)
- feed temperature
- test piece temperature
- speed
- torque
Air-condtioning chamber
[Picture Machine]
Air-conditioning unit construction
Circulating-air-conditioning unit consists of compact-type cabinet. Lower part holds refrigerating unit, in upper part air-conditioning system is installed. Test chamber connection is made by flexible, insulated tubes. Test chamber consists of 120 mm insulated elements, some fixed to test stand and others removable for inspection. Air-conditioning unit is designed for heating speed 2 Grad C/min., cooling speed 1 Grad C/min. and test piece weight 60 kg.
Operation part
Separate operation rack (19″) is connected with unit by plug-in cable (20 m). It holds temperature control with digital set-value selector and digital true-value indication, ON/OFF switch, function control lamps and failure indication.
Technical data
Unit dimensions:
height appr. 1850 mm, width appr. 1500 mm, depth appr. 1000 mm
test chamber vol.: appr. 950 l
overall dimensions:
height appr. 1400 mm, width appr. 1100 mm, depth appr. 1200 mm
temperature range: – 30 to + 120o C
temperature constancy: +/- 2.0o C
water cooled refr. unit: 6 kW
refrigerant: R 502
mains supply: 220/380 V/50 Hz
connected load: appr. 25 kVA
