Round tube outer diameter measuring instrument

The utility model provides a circular tube outer diameter measuring instrument, and belongs to the technical field of measuring equipment. The problem that an existing circular tube outer diameter measuring instrument is insufficient in measuring accuracy is solved. The circular tube outer diameter measuring instrument comprises a measuring instrument body with a radius gauge and a positioning frame fixedly connected with the measuring instrument body, the positioning frame comprises a positioning block which is arranged corresponding to the radius gauge side by side, a V-shaped positioning groove is formed in the front end face of the positioning block, and the side wall faces of the two sides of the positioning groove can be tangent to the outer side face of a circular tube at the same time. Compared with an existing measuring instrument, the measuring instrument for the outer diameter of the circular tube can improve the measuring accuracy. 本实用新型提供了一种圆管外径测量仪，属于测量设备技术领域。它解决了现有圆管外径测量仪的测量准确性不足等问题。本圆管外径测量仪，包括具