Abstract: Disclosed are an adjustable load pressure compensation balancing system, an end cover, and a counterbalance valve. The adjustable load pressure compensation balancing system comprises: an adjustable orifice control module and a counterbalance valve control module, wherein the adjustable orifice control module is used for receiving control oil generated when a luffing system descends and oil from a descending cavity of a luffing cylinder; the counterbalance valve control module is used for receiving the control oil generated when the luffing system descends; the pressure applied to the counterbalance valve control module by the control oil is maximum when the luffing system starts to descend, and then decreases gradually; and the pressure applied to the adjustable orifice control module by the oil from the descending cavity is minimum when the luffing system starts to descend, and then increases gradually.

Abstract: A modular design gearbox and a gear implementation method are provided. The gearbox includes a body, a drive shaft, four intermediate shafts, and an output shaft. The gearbox is of a six-shaft layout. The drive shaft S1, the intermediate shaft S4 and the intermediate shaft S5 are each provided with two clutch packs, and the intermediate shaft S2 is provided with one clutch pack. According to such a structure, a transmission path is short, and stability is better. By means of six shafts and seven clutches, the gearbox achieves a mode of up to eight forward gears and four backward gears, a speed ratio range is wide, and the gearbox can be adjusted flexibly, a less-gear mode can be achieved by reducing some of components, modularization is achieved, universality is improved, and the production cost and use cost of the gearbox are reduced.