Because of the chemical stability,nitrogen is often used as the protective gas inside the modern missile storage and transportation launch canister,which provides a stable and dry atmosphere environment for the products in the canister.At present,the troops often use standard nitrogen bottles to fill directly,however,the conditions for filling nitrogen cylinders are not available in remote areas with limited traffic such as tactical positions.Based on the above requirements,a modular nitrogen producing and filling equipment was designed.The hollow fiber membrane permeation principle was adopted to prepare nitrogen in the equipment.The purity of the prepared nitrogen is more than 9995%,and the dew point is less than -60 ℃,which is better than the standard nitrogen.All nitrogen production indexes of the equipment are better than the specified requirements,which can meet the requirements of nitrogen filling in the storage and transportation launch canister.