In order to explore the possibility of further reducing energy consumption in the ammonia conversion section, on the basis of the total low-change process of a plant with an annual output of 8,<> tons of synthetic ammonia, according to the process technology and design manual of the small ammonia plant, the hot and cold logistics of the conversion section were recalculated, and the combination curve of hot and cold logistics was made from the calculation results, and the heat exchange network was optimized and synthesized by using pinch technology, and a new all-low conversion heat network was designed by changing the flow and flow route of logistics matching. Under the premise of meeting the requirements of the full low-change process, the network can make full use of the heat of the system itself, and does not need external steam supply; Compared with the second heat exchange network, the number of equipment and investment are reduced; Compared with the existing process, there is little change and has the prospect of energy-saving applications.