| 摘要 |
<p>The hydraulic life is particularly for personnel, comprising a ram with piston and rod, the piston being raised by water pressure underneath it. The piston rod (2) rests freely on the piston (5), its end being typically of part-spherical section (7) acting against a plastic component (8), over which it can slide. The design avoids the risk of the piston canting in the cylinder, with consequent risk of leakage past it.</p> |
