Taking NC macro program in spherical ring-cutting as example,the paper puts forward the convenience of NC macro program in programming for complicated components,and points that the design of feed route is critical in NC programming.

In the process of drawing up the technology route of numerical- controlled machine toolsin processing parts,if limited to the Parts themselves,the feed route drawn up may not bethe shortest and it is possible that difficulties may arise in programming.

The power transmission line corridor is very narrow in East China for San-Hu DC transmission line,the cost of residential house clearing is expensive as the polar conductors horizontally arranged.

Transmission line corridor problem is prominent during current line constructions in our country.

The situation of large load density and lack of line corridors of East China area is worsened by increased difficulties in building dismantling and substantially increased economic compensation,which has seriously impeded the grid development.

In this paper,the mathematic model of bus routing problem,which takes the maximum sum of dynamic nonstop passengers with bending modulus restricted,is established and the solution algorithm based on ant colony algorithm is developed.

Wether the tool path is right or not will make differences to the machining quality and productivity.

Rational determination of the tool path in NC machining plays very important roles to ensure the machining accuracy and surface quality of the parts to be machined as well as to improve the efficiency of programming and processing.