Background Whether it is a trunk line or a metropolitan area network, underground pipe hole resources are very tight. Compared with ordinary cables, the use of air-blown micro-cables can save nearly 50% of the resources in pipe holes. The typical structure of the air-blown micro-cable system is mother pipe-micro-pipe-micro-cable. The mother pipe can be placed in the concrete pipe hole, and new routing construction can also be carried out. In the already laid HDPE or PVC parent tube, or pre-lay the parent tube and micro-tube on the newly-built optical cable route, it can be blown through the tube or blown...