Based on practical operation, the application of the PLC in pulse tracing of the pulse counter blowing controller in bag filter and logic option of handling material distribution to multi silos from single sending unit is introduced.

Technology tracking is a useful method in identifying the current situation and trend of development in related technical areas,and ean help us provide the information decision-making support for establishment of technical strategy,but the in- depth research of technology tracking is not enough.

The article makes preliminary discussion on the mode of technology tracking,puts forward four kind of modes of technology tracking,simultaneously to analysis the influencing factors of technology tracking mode,forms the theory frame of the technology tracking mo.

Founded on concept explanation, the article makes preliminary discussion on the structure and process of technology tracking, developed tools of technology tracking based on patent quotation, which as a kind of technical analysis is fundamental to of technology strat.