波纹管的定位直接关系预应力束施工质量，而预应力束的位置和形状准确与否，将直接影响梁体内应力分布。根据预应力束的直线和曲线形状，准确计算出各预应力孔道每隔1m左右的标高和水平投影位置，按预应力曲线矢高在控制点处箍筋上画线，焊接U形定位支架，将波纹管固定在支架上，以保证预应力孔道位置与设计相符。铺管时，先将固定端锚垫板安装就位，从张拉端处逐步套人波纹管。螺旋管安装就位过程中，应尽量避免反复弯曲，以防管壁开裂。同时，还应防止电焊火花烧伤管壁。
The positioning of bellows is directly related to the construction quality of prestressed tendons, and the accuracy of the position and shape of prestressed tendons will directly affect the stress distribution in the beam. According to the straight line and curve shape of the prestressed tendon, accurately calculate the elevation and horizontal projection position of each prestressed duct every 1m or so, draw a line on the stirrup at the control point according to the rise height of the prestressed curve, weld the U-shaped positioning bracket, and fix the bellows on the bracket to ensure that the position of the prestressed duct is consistent with the design. During pipe laying, the anchor base plate at the fixed end shall be installed in place, and the bellows shall be sleeved gradually from the tensioning end. During the installation of spiral pipe, repeated bending shall be avoided as far as possible to prevent the pipe wall from cracking. At the same time, the electric welding sparks should be prevented from burning the pipe wall.