现今，氮越来越多地被用于冷却铝合金挤压模，以增加挤压速度、提高模具寿命和改善型材的表面质量。介绍了挤压中的“额外加热”概念。叙述了一般性原理及模具冷却的特殊原因，对合理使用液氮或气氮的冷却提出了建议。用图表示出挤压车间氮冷的平面布局，并将工业实践数据列表作为参考。 Today, nitrogen is increasingly used to cool aluminum extrusion dies to increase extrusion speed, increase tool life, and improve the surface quality of the profiles. The concept of “extra heating” in extrusion is introduced. The general principle and the special reasons of mold cooling are described, and some suggestions for the rational use of liquid nitrogen or nitrogen gas cooling are put forward. Graphical showing the floor plan of the nitrogen-cooled extrusion plant with a list of industrial practices as a reference.