介绍便携式超声波应力检测仪的工作原理及使用效果。由于该检测仪可在使用现场准确而快捷地测试车轮及钢轨的内应力，及时发现导致车轮及钢轨破损的残余应力，从而在提高行车安全上发挥重要作用。该仪器已在美国、欧洲及日本等地使用 Introduce the portable ultrasonic stress detector works and the use of results. As the tester can accurately and quickly test the internal stress of the wheel and the rail at the site of use, it can play an important role in improving the driving safety by detecting the residual stress resulting in the damage of the wheel and the rail in time. The instrument has been used in the United States, Europe and Japan