ＺＴＱ４０型自升塔式起重机在使用中发现变幅减速器与电动机连接法兰处经常漏油，拆下检修后发现法兰接合面处石棉垫损坏，更换新垫后，不久又开始漏油，高空拆卸也极不方便，影响了施工。对该机的变幅减速器与电动机的结构及连接形式（图１）进行了分析，发现密封方式不够完 ZTQ40-type jack-up cranes found in the use of variable speed reducer and the motor connected to the flange often leak oil, remove the overhaul and found flange joints asbestos pad damage, replace the new mat, and soon began to leak, High-altitude demolition is also very inconvenient, affecting the construction. The aircraft’s amplitude reducer and motor structure and connection form (Figure 1) were analyzed and found that the sealing is not enough