Brake Lining Friction Test Rig

Main features

  1. It is compact in constructions and conforms to the I.S. 2742: 1964.
  2. A strip chart record is used to give direct record of pressure and temperature through suitable sensor during the test.
  3. Pneumatic circuit makes the system semi-automatic.
  4. More confirmatory results can be tasted.
  5. Most confirmatory result of coefficient of friction and hence the wear resistance can be obtained.

Specifications

  1. Test Evaluation: Coefficient of frication of friction materials.
  2. Method of Test: Guirling scale friction method by using constant torque conditions.
  3. Running speed of the rubbing surface: 1530-1550 rpm.
  4. Mean radius of rubbing: 32
  5. Wrap-angle of lining sample on holder: 210
  6. Sample I.D.: 50mmØ O.D.: 80mmØ
  7. No. Of test pieces: 6 Nos.
  8. Torque arm length: 300mm
  9. Maximum normal drag on the diaphragm of 7800mm2 area (approx): 500 kgs
  10. Driving Motor :03 H.P., 3Phase, 440 V.
  11. Auto feed back mechanism for torque application: 50 C.P.S.
  12. Cooling means: F.H.P. O, 2800rpm. Air blower.

Purpose & Utility

The purpose of brake lining friction test rig designed and developed by ARE is to generate performance data for R & D, Quality Control departments. The data helps in evaluation of friction and were characteristics of brake lining.

Tests to be performed

Tests suggested as per IS: 2742-1964 can be carried out on this Test Rig. Which also confirms to draft specifications EDC (38) 3367:1979.

Friction Test

The test specimens shall be tasted on this Test Rig. The machines may be on the scale dynamometer type using constant torque. Description of test method that may be adopted for the determination of the coefficient of friction for the determination of the coefficient of friction are as given below.
  1. Normal Test.
  2. Wear Test.
  3. Wet Friction Test.
  4. Heat Test.

Normal Test


The first cycle of normal test with the test machine shall be conducted 20 minutes with a load of 3.515 kg/cm2 on the samples with cooling air blowing on- the torque head so that temperature of the friction disc shall not be more than 1000 C. During the first few minutes of the cycle the surface of the test pieces shall be normalized by rubbing auction on the surface so as to obtain uniform surface giving total contact with the friction shall be calculated over the steady portion of the graph.

Heat Test

This test shall be interposed between the two cycles of normal test. The heat test shall be similar to the torque head is cut off, so that he friction disc temperature is rises to 150 to 1750C. The average value of co- efficient a nearly co-efficient of friction after the friction disc attained a nearly constant high temperature during the test shall be with in the limits.

Wear Test

The thickness loss suffered by the test specimens after the tests described in Normal Test & Heat Test above shall be measured. For each test the rate of wear shall be specified in terms of unit loss in volume per unit of work done, for example-cm3/kWh (or in3/hp.h).

Wet Friction Test

After the completion of the tests described in normal test, heat test, wear test the test pieces shall be placed in water for two hours & the normal test carried out as in normal test.