Sample Line Pull Calculation:
|
I. Data Required |
|
| A. Unit weight of live load | 50 lbs. |
| B. Unit weight of attachment | 5 lbs. |
| C. Total live load | 55 lbs. |
| D. Maximum number of total loads on system | 300 |
| E. Dead load ( Cable, trolley, etc) | 4lbs. per foot |
| F. Total system length | 300ft |
| G. Total elevation change | 10ft |
| H. Coefficient of friction | .03 |
| I. Load per foot (Item II.3 blow ÷ “F”) | 59 lbs. / FT |
| II. Line Pull Calculation (Monoplane) | |
| 1.
Total live load x number of
loads |
16500 lbs. |
|
(“C” x “D”) |
|
| 2. Dead load x system length | 1200 lbs. |
|
(“E” x “F”) |
|
| 3. Total load on system | 17,700 lbs. |
|
(Add line 1&2 above) |
|
| 4. Multiply line 3 above x .03 |
x.03 |
| 5. Line pull for monoplane | 531 lbs. |
| III. Line Pull for Inclines/Declines (Multiplane Only) | |
| 1.
Add for inclines – load per foot x elevation change
|
590 lbs. |
|
("I" x "G") |
|
| *2. Deduct for declines – Load per foot x elevation change ÷ 1.3 | 453 lbs. |
| 3. Subtract deduct for decline from add for incline | 136 lbs. |
| IV. Total Line Pull | |
| Add paragraph II item #5 and paragraph III item #3 | 667 lbs. |
|
* If system is
to be unloaded at declines, omit step III. |