Weibull Database

Weibull databases require considerable use of engineering judgment for meaningful application of the facts stored in database format. Do not apply the data blindly without understanding the specific situation, as this database is solely intended for educational purposes.

Data, described in this database, are very general. The facts are broad as is usually found in engineering references. Typical values are given for a specific case which may not be applicable for each condition envisioned by the end user of the database as exceptions always exist. Therefore you are the sole responsible individual for use of this table--Barringer & Associates, Inc. assumes no liability for your use/misuse of these tables in any manner either obvious or implied.

Item

Beta Values

Eta Values

 

(Weibull Shape Factor)

(Weibull Characteristic Life--hours)

Low

Typical

High

Low

Typical

High

Components

 

 

 

My engineering judgment does not support the range of a few values shown in published databases

Ball bearing

0.7

1.3

3.5

14,000

40,000

250,000

Roller bearings

0.7

1.3

3.5

9,000

50,000

125,000

Sleeve bearing

0.7

1

3

10,000

50,000

143,000

Belts, drive

0.5

1.2

2.8

9,000

30,000

91,000

Bellows, hydraulic

0.5

1.3

3

14,000

50,000

100,000

Bolts

0.5

3

10

125,000

300,000

100,000,000

Clutches, friction

0.5

1.4

3

67,000

100,000

500,000

Clutches, magnetic

0.8

1

1.6

100,000

150,000

333,000

Couplings

0.8

2

6

25,000

75,000

333,000

Couplings, gear

0.8

2.5

4

25,000

75,000

1,250,000

Cylinders, hydraulic

1

2

3.8

9,000,000

900,000

200,000,000

Diaphragm, metal

0.5

3

6

50,000

65,000

500,000

Diaphragm, rubber

0.5

1.1

1.4

50,000

60,000

300,000

Gaskets, hydraulics

0.5

1.1

1.4

700,000

75,000

3,300,000

Filter, oil

0.5

1.1

1.4

20,000

25,000

125,000

Gears

0.5

2

6

33,000

75,000

500,000

Impellers, pumps

0.5

2.5

6

125,000

150,000

1,400,000

Joints, mechanical

0.5

1.2

6

1,400,000

150,000

10,000,000

Knife edges, fulcrum

0.5

1

6

1,700,000

2,000,000

16,700,000

Liner, recip. comp. cyl.

0.5

1.8

3

20,000

50,000

300,000

Nuts

0.5

1.1

1.4

14,000

50,000

500,000

"O"-rings, elastomeric

0.5

1.1

1.4

5,000

20,000

33,000

Packings, recip. comp. rod

0.5

1.1

1.4

5,000

20,000

33,000

Pins

0.5

1.4

5

17,000

50,000

170,000

Pivots

0.5

1.4

5

300,000

400,000

1,400,000

Pistons, engines

0.5

1.4

3

20,000

75,000

170,000

Pumps, lubricators

0.5

1.1

1.4

13,000

50,000

125,000

Seals, mechanical

0.8

1.4

4

3,000

25,000

50,000

Shafts, cent. pumps

0.8

1.2

3

50,000

50,000

300,000

Springs

0.5

1.1

3

14,000

25,000

5,000,000

Vibration mounts

0.5

1.1

2.2

17,000

50,000

200,000

Wear rings, cent. pumps

0.5

1.1

4

10,000

50,000

90,000

Valves, recip comp.

0.5

1.4

4

3,000

40,000

80,000

 

 

 

 

 

 

 

Machinery Equipment

 

 

 

 

 

 

Circuit breakers

0.5

1.5

3

67,000

100,000

1,400,000

Compressors, centrifugal

0.5

1.9

3

20,000