To obtain a mid-infrared HF laser with high repetition rate and high power, a closed-circle pulse-periodical non-chain HF chemical laser with self-acting ultraviolet pre-ionization and a pair of symmetrical Chang electrodes is developed. The design and performance of the developed laser are described in detail. An experimental study on the laser output and repetition rate operation characteristics demonstrates the effect of repetition rate on pulse energy. The average power for a HF laser with a repetition rate of 150 Hz is approximately 200 W when the gas flow speed is 16 m/s in the gain region, working voltage is 25 kV, and the total mole fraction pressure of 92% SF6 and 8% C2H6 gas mixture is 8.5 kPa.