基本解释门式起重机；龙门吊车英汉例句双语例句A brand-new jib-bridge luffing system of crane is brought out based on analysis of the limitation to handle containers of the portal crane.在分析门座起重机用于集装箱装卸作业的局限性的基础上，提出一种新型的起重机变幅系统。portal jib crane更多例句词组短语短语travelling portal jib crane 门式移动悬臂起重机;移动式悬臂吊车double portal jib crane 双龙门吊portal jib crane更多词组专业释义机械工程门座式起重机经济学门式起重机