Abstract:  The hydraulic rock drill generally adopts the independent external rotating mechanism. Compared to the impact mechanism， there are few researches on it. Based on the theoretical analysis of the main rotary performance parameters of hydraulic rock drill， including rotary torque， rotary speed， rotary power， etc.， and according to the requirements of national standards， a set of rotary performance test system of hydraulic rock drill is developed in this study， and a small-type hydraulic rock drill is used as the test model to test its rotary performance under low flow and large flow. The data analysis and curve fittingshows that there is a good linear relationship between rotary torque and rotary oil inlet pressure. Within a certain range of rotary torque， the torque-speed curve keeps a good performance (speed is stable)， where the load exceeds the torque， and the rotary speed drops rapidly.

Key words:  Hydraulic rock drill, Rotary characteristics, Theoretical analysis, Performance parameters