What are the main failure modes of the triangular belts, described as follows: (1) The belt slips on the pulley and cannot transmit power. (2) Delamination, tearing and breaking of the belt due to fatigue. (3) Wear of the working surface of the belt. (4) Torsional vibration of the driven shaft. To ensure that the belt does not slip during work, and has a certain fatigue strength and service...