| 摘要 |
<p>The oval or pear-shaped hoisting ring is of rectangular section at the ends (2), and of I-section at the central portions (3). This central portions can be thicker at their inner faces that at their outer ones, and thinner than at the ends. The ring can be wider at the central portion than at the ends. Compared with conventional rings, the ring is of lighter weight, with the same resistance to tensile forces.</p> |
