Roller Chain
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The information on this page is distilled from Wikipedia's page on Roller Chain. The original text is released under a CC-BY-SA 3.0 license. |
[edit] ANSI Roller Chain Data
The following table shows the principal data of ANSI standard B29-1 (Precision Power Transmission Roller Chains, Attachments, and Sprockets).
| Size (ANSI) | Pitch (Inch) | Roller diameter (Inch) | Tensile strength (lbs) | Working load (lbs) |
|---|---|---|---|---|
| 25 | 0.250 | 0.130 | 781 | 140 |
| 35 | 0.375 | 0.200 | 1758 | 480 |
| 41 | 0.500 | 0.306 | 1500 | 500 |
| 40 | 0.500 | 0.312 | 3125 | 810 |
| 50 | 0.625 | 0.400 | 4880 | 1430 |
| 60 | 0.750 | 0.469 | 7030 | 1980 |
| 80 | 1.000 | 0.625 | 12500 | 3300 |
| 100 | 1.250 | 0.750 | 19531 | 5072 |
| 120 | 1.500 | 0.875 | 28100 | 6800 |
| 140 | 1.750 | 1.000 | 38280 | 9040 |
| 160 | 2.000 | 1.125 | 50000 | 11900 |
| 180 | 2.250 | 1.460 | 63300 | 13700 |
| 200 | 2.500 | 1.562 | 78000 | 16000 |
| 240 | 3.000 | 1.875 | 112500 | 22250 |
Notes:
1. The pitch is the distance between roller centers. The width is the distance between the link plates (ie slightly more than the roller width to allow for clearance).
2. The right-hand digit of the standard denotes 0 = normal chain, 1 = lightweight chain, 5 = rollerless bushing chain.
3. The left-hand digit denotes the number of eighths of an inch that make up the pitch.
4. An "H" following the standard number denotes heavyweight chain. A hyphenated number following the standard number denotes double-strand (2), triple-strand (3), and so on. Thus 60H-3 denotes number 60 heavyweight triple-strand chain.
[edit] Rules of Thumb
- Replace a roller chain which has elongated:
- 3% on an adjustable drive or
- 1.5% on a fixed-center drive
- The lengthening of a chain is calculated by the following formula:
- % = ((M-(S*P)) / (S*P)) * 100
- M = the length of a number of links measured
- S = the number of links measured
- P = Pitch
- The standard minimum ultimate strength of the ANSI 29.1 steel chain is 12,500 x (pitch, in inches)2.
- Typical Safety Factors:
- Continuous drive
- 1:6 of tensile strength for press-fit master links
- 1:9 of tensile strength for slip-fit roller links
- Continuous drive
