Lub rooj vag hydrodynamic Tsis siv neeg dej nyab yog ua los ntawm cov hlau tsis muaj steel, aluminium thiab roj hmab, cov txheej txheem khaws dej yog lub hauv paus ntsiab lus ntawm lub cev, tsis muaj hluav taws xob, tsis muaj cov neeg ua haujlwm, muaj kev nyab xeeb thiab txhim khu kev qha. Piv nrog hydraulic zog lossis lwm yam, tsis muaj kev pheej hmoo ntawm hluav taws xob poob lossis tsis ua haujlwm yam tsis muaj hluav taws xob.