QPQ treating solves rusty problems for concrete pump truck boom connecting pins. Analysis and comparison are implemented in the pins’ fatigue lives with QPQ and ordinary thermal refining. Method feasibility is verified,fatigue reliability being the theoretical basis. Maximum bending moment helps calculate the allowable fatigue load. Test-tooling simulates the assembly structures and actual working conditions. The results show that QPQ treatment slightly influences the surface hardness and fatigue life. References and bases are provided for the design calculation and surface treatment. QPQ treatment pins are trialproduced and they do well in some concrete pump trucks.