一台浦沅工程机械厂制造的35 t起重机,由于旋转密封严重外泄,对其解体维修(见图1)。该密封中心轴上有7道环形槽用于安装密封件7和8,防止液压油泄漏。环形槽宽度为8 mm,每道环形槽内先装一道O形圈,再将每道O形圈套上宽度为7.5 mm、截面为矩形的骤缩醛树脂 A 35 t crane manufactured by Pu Yuan Construction Machinery Factory was disassembled and repaired due to a serious leakage from the rotary seal (see Figure 1). There are seven annular grooves on the seal center shaft for the seals 7 and 8 to prevent leakage of hydraulic oil. The width of the annular groove is 8 mm. First, an O-ring is installed in each annular groove, and each O-ring is covered with a 7.5 mm wide cross-section of the resol resin