1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards WHEEL BEARING TEST (EXCEPT FOR RIGID AXLES) Do Not Use on New Programs. Being Replaced by GMW14840 EDS-T-2530 ISSUED DATE: 1996. 07. 10 REVISED DATE: 2008. 10. 23 VERSION: 4 (Superceded) EDS-T-2530WHEEL BEARING TEST (
2、EXCEPT FOR RIGID AXLES) PAGE: 1/3 ISSUED DATE: 1996. 07. 10 REVISED DATE: 2008. 10. 23 VERSION: 4 GM DAEWOO Auto & Technology Note: This standard may be applied only for current project (incl. T255 Program). It is Superceded for all future projects and replaced by GMW14840. 1. PURPOSE Determination
3、of the wheel bearing life expectancy for quality control purposes or releasing a further supplier. 2. EQUIPMENT Test machine as shown on picture 1 and 2, using the following parts: 6 air actuators 2 drive motors (1.4 kW) 1 control desk and various clamping elements 3. PROCEDURE 3.1. Test preparation
4、 3.1.1. Dimensional check of bearing seats and bearings 3.1.2. The bearings are to be completed and mounted to mounting specification (refer to drawing). In order to prevent operational deformation, the fixture must be extremely rigid. In addition, the genuine connecting parts such as hub, steering
5、knuckle and wheel soindle are to be used. New parts must be used for every single test. In case of bearing elements to be pressed in or on, the pressing forces are to be recorded. 3.1.3. For bearings with axial preload, the stall torque for the nut is to be recorded. 3.1.4. Apply wheel load FRthroug
6、h the center of tire contact (disregarding wheel camber) and FSthrough the effective rolling radius and adjust according to drawing specification. 3.2. Test 3.2.1. Bearing speed: 1,200 min-13.2.2. Alternating load according to wheel load as indicated under 3.1.4 3.2.3. One test cycle is 12 sec. and
7、consists of 5 sec. increased radial force FR1(outer wheel in curve driving) with simultaneous lateral load FS1(lateral acceleration 0.6 g inboard), followed by 1 sec. straight ahead driving FE3. Subsequently 1 sec. reduced radial force FR2(inner wheel in curve driving) with simultaneous lateral forc
8、e FS2(lateral acceleration 0.6 g outboard) followed by 1 sec. straight ahead driving FR3(for function sketch refer to drawing specification). The change in load shall take 0.5 to 1 sec. (achieved by increasing the pressure in the air actuators). 3.2.4. Every bearing is to be heated to 95 to 105 at t
9、he specified bearing speed under no load. After that, every bearing is to be heated under load to 135 to 145 within 30 minutes at the most. This temperature is to be EDS-T-2530WHEEL BEARING TEST (EXCEPT FOR RIGID AXLES) PAGE: 2/3 ISSUED DATE: 1996. 07. 10 REVISED DATE: 2008. 10. 23 VERSION: 4 GM DAE
10、WOO Auto & Technology maintained for 40+5minutes under test conditions. Subsequently maintain the cooling in a manner that the temperature will be 6510 K during the remaining test time (applies only to double row ball bearings). The temperature shall be 6510 K during the remaining test time (applies
11、 only to double-row ball bearings). The temperature shall be 6510 K throughout the test (applies only to tapered-roller bearings). 3.2.5. The bearing test will be terminated if (1) The current consumption of the drive motors increases by 10 15 % (2) The noise level increases (audio check) (3) Survey
12、 by a frequency generator 3.3. Test evaluation 3.3.1. Determine bearing clearances and preload by means of residual torque of the nut. 3.3.2. Check lip seals for irreproachable seat 3.3.3. Check firm seat and determine pressing-out forces 3.3.4. Check contact surfaces and rollers for pitting, smears
13、, wear, etc. 3.3.5. The results of 10 to 15 bearings from 1 supplier and one batch shall be recorded in a chart according to the functional normal distribution of the survival probability. 3.3.6. Determination of the grease residue for self sealing bearings 3.3.7. The theoretical running time for Ps
14、 90 % and the permissible diffusion between 90 and 10 % can be taken from the drawing specification. EDS-T-2530WHEEL BEARING TEST (EXCEPT FOR RIGID AXLES) PAGE: 3/3 ISSUED DATE: 1996. 07. 10 REVISED DATE: 2008. 10. 23 VERSION: 4 GM DAEWOO Auto & Technology Fig 1. Control desk with several clamping elements (front/rear wheel bearings) Fig 2. Test Fixture front/rear wheel 1. Air actuator 2. Air actuator 3. Load application arm 4. Hot air blower 5. Test bearing (not visible) 6. Drive motors
