bob weight
2.Rotor bob-weight part is one of the most important parts of helicopter, which requires strict precision of the shape bend, surface quality, chemical composition, mechanical properties, and weight warp be controlled in a mini confine.
3.The additional bob-weight is specially designed to improve the performance of small four-wheel tractor with an 8.8~11 kW engine for plowing in dryland.
4.The experiment results approve that the opener has good performance of anti-blocking, but it needs biggish positive press. When the bob-weight is 350 kg and the gross weight is 570 kg, the performances of penetrating depth and cutting stubbles are excellent in trials, which makes sure that the opener is worth of research.

