Abstract
We tested the main characters of the straw-rope and the roper, and results obtained in test are as follows.
When the lower twist pitch equaled to upper twist, the deformation of the shape of the rope is a litte and such ropes are most safe.
When the lower twist brying on 0.4 to 0.6 pitch per 1 pitch of upper twist with 7 to 9 pitches per 30cm in length at 10φ rope, the tensile strength. attain to about maximum,
The turning slip between the rolling disk and the friction roller increased according as increasing the diameter or the turning speed of the rolling drum, and such relations are showed by curved line at the former, and straight line the later.
