Abstract：The mechanical principle of volume borehole strain gauge is simple and reliable data can be obtained easily, but it is limited by its size. The diameter of existing TJ-2 body strain installation hole must be greater than 130mm, and the drilling cost is high. In order to reduce drilling expenses, we research the miniaturization of volume borehole strain gauge and calculate the sensitivity coefficient and apparent compression modulus of volume borehole strain gauge. According to the calculation results and the material technology, we develop a strain gauge which is suitable for drilling holes with a diameter of 110 mm.
