可靠性测试资料

@2002 Sunonwealth Electric Machine Industry Co, Ltd. All right reserved
L10 Calculation
1. Random sampling 50 pcs 2. Perform function test in advance and temperature set up. 3. Function test once a week. 4. Continue test till 10% failure being found , then terminate. 5. Count total test hours ( T ) and failure quantity ( r ). 6. Get the observe MTTF.
Example: Sampling 50 pcs / test for 16024 hours. 1 pc TTF at 6872 hrs , 1 pc TTF at 9584 hrs , 1 pc TTF at 12468 hrs , 1 pc TTF at 14568 hrs , 1 pc TTF at 16024 hrs . Exponential distribution Total test hours( T ) : (6872 x 1) + (9584 x 1) + (12468 x 1) + (14568 x 1) +(16024 x 1) + (16024x 45) = 780596 hrs
R (t ) = e
(△ H)
Sample Size
Stress elevated 70℃ Actual test tim e required test tim e w ith zero failure T w ith zero failure T (hour) (hour)
Sleeve
8hrs/dayx365days/ yearx2years = 5,840 hrs
0.5
50 Pcs
2739
3000
MTTF Procedure
1. Random sampling 50 pcs. 2. Perform function test in advance and set up temperature. 4. Function test once a week. 5. Test time for 2160 hrs (3 months). 6. Based on Total Test Hours( T ) and Failure Quantity ( r ) and refer Chi-Square table with Confidential Level (CL) to get MTTF.
Sunonwealth Electric Machine Industry Co., Ltd
Reliability Presentation
Contents
◎Reliability Test Equipment/Item. ◎Fan MTTF/L10 Test Procedure And Calculation Method .
8hrs/dayx365days/ yearx5years = 14,600 hrs
0.95
170,783 hrs (180,000 hrs)
0.4
50 Pcs
2268
2520
0.95
227,710 hrs (230,000hrs)
0.45
50 Pcs
2466
2520
0.95
284,638 hrs (300,000 hrs)
0.95
113,855 hrs (120,000 hrs)
0.3
50 Pcs
2096
2160
Fra Baidu bibliotek
1Ball 8hrs/dayx365days/ yearx3years 1Sleeve = 8,760 hrs 1Ball 8hrs/dayx365days/ 1Sleeve yearx4years + MS = 11,680 hrs VAPO 2 Ball
MIL-HDBK781A
Design M/P
2.Temperature/Humidity Test Machine
Test Item
Temperature Cycle Test
Test Condition
Low Temperature : --25℃±2℃ High Temperature : 70℃/ 90 ℃ ±2℃ Dwell Time : 2 hrs/each Transfer Time : 1.5 hrs Cycle : 50 cycles Min •Low temperature:-40℃±2 ℃ •High temperature:80 ℃ ±2 ℃
Standard
IEC68-2-38
Status
Remark
Design
Thermal Shock Test Low Temperature Test
• Dwell time:30 mins/each •Temperature transfer ramp rate:30 ℃/min •Cycle:100 minimum.
T
MTTF =
r
7. L10 = 0.105 x MTTF By ( R90 ) = e -λL10 to get the constant of L10 (0.105)
@2002 Sunonwealth Electric Machine Industry Co, Ltd. All right reserved
IEC 68-2-14
Design
Temperature : -25℃±2℃ Applied Voltage : Rated voltage Duration : 96 hrs Temperature : 60±2℃ Humidity : 93±3%RH Duration : 96 hrs Applied Voltage : Rated voltage
Standard
Status
Remark
IEC68-2-6 Design M/P
6.Ball Bering Test Machine
Test Item Test Condition
Low Band : 30 - 300 Hz Med Band : 301 – 1800 Hz High Band : 1801 – 10 KHz
Standard
Status
Remark
Mechanical Shock Test
IEC68-2-27
Design
Fan MTTF / L10 Test Procedure And Calculation Method
The definition of MTTF with difference structure
Standard
Status
Remark
Air Flow / Static Pressure Test
ANSI AMCA210-99
Design
4.Acoustic Test System
Test Item Test Condition Sound Pressure Time Weighting : Slow Freq. Weighting : A weighting Background : 15+/-2dB(A) Distance : 1 M Band Range : 16 Hz – 20 KHz Microphone : B&K 4179 Spectrum analyze : B & K 3560 Fan Noise / Vibration Test Sound Power Test Point : 10 Points Background : 15+/-2dB(A) Area Of Measure Surface : 6.3M2 Band Range : 100Hz ~ 20KHz Sound Quality Freq Weighting : A Weighting Background : 15+/-2dB(A) Measure System : Head Acoustic System Vibration Test R.M.S Vibration : Velocity mm/sec R.M.S Freq Range : 0 ~ 5 KHz Standard Status Remark
Standard
Status
Remark
Drop Test
IEC68-2-32
Design M/P
8. Mechanical Shock Test Machine
Test Item Test Condition
Pulse Shape : Half-Sine Wave Nominal Pulse Length : 2 ms Velocity:60in/sec(Op) & 80in/sec(Non-Op) Number of shock:3Shock for each six faces
CNS-8753 JIS B-8346 ISO-7779
ISO-7779
Design
M/P
ISO-532B
ISO-10816-1
5.Vibration Test Machine
Test Item Test Condition
Sine Wave Vibration Range of Frequency : 5-55-5 Hz Amplitude : 2 mm Duration : 30 mins Vibration Test Random Vibration Range of Frequency : 20-500 Hz PSD : 0.98G(OP)/2.2G(Non-OP) Duration : 60 mins per axis IEC68-2-34
IEC68-2-1
Design
Humidity Test
IEC68-2-3
Design
3.Air-Flow/Pressure Test System
Test Item Test Condition
Applied Voltage : Rated voltage Barometric Pressure : 76 cm-Hg atmospheric pressure
Standard
Status
Remark
IEC68-2-2
Design
Impeller Locked Test
Temperature : 70℃/90℃±2℃ Voltage : 115% Duration : 168 hrs
UL-507
Design
Life Test
Temperature : 70℃/90℃±2℃
Total test hours( T ) : (2400 x 1) + (2736 x 1) + (3000 x 48) = 149,136 hrs Chi-Square table : 90% CL, 2 pcs failed, get a coefficient 10.6
MTTF = (2 x T) / 10.6 = (2 x 149,136) / 10.6 = 28,138 hrs.
Standard
Status
Remark
Ball Bearing Test
ISC
IQC/ Analysis
7.Drop Test Machine
Test Item Test Condition
Height : Follow Standard One angle, three diagonal corners, six planes
@2002 Sunonwealth Electric Machine Industry Co, Ltd. All right reserved
MTTF Procedure
Formula: MTTF = ( 2 x T ) / ( X2 , α , 2r+2 )
Example : Sampling 50 pcs / test for 3000 hours 1 pc TTF at 2400 hrs , and another TTF at 2736 hrs.
Reliability Test Equipment/Item.
1.High Temperature Test Equipment
Test Item
High Temperature Test
Test Condition
Temperature : 70℃/90℃±2℃ Applied Voltage : Rated voltage Duration : 96 hrs
Acceleration Factor
Structure
Power on hour at 40℃
(POH)
Reliability requirement
− t θ
Acceptable the MTTF at 40℃
〔 AF = e
Activation energy
(△H/K)x(
1 1 − ) T-Field T-Test 〕