| 摘要 |
Front and rear pairs of crawler assemblies are provided for supporting separated ring segments disposed forwardly under the boom and rearwardly under the counterweight so the crane can travel under load and swing through at least a partial horizontal arc with separate pivots for the boom and counterweight. One and preferably both crawler assemblies are selectively and reversely powered to facilitate forward and reverse as well as turning movement during travel under loaded and unloaded conditions. |
