Abstract:The drilling mast equipped with the imported DMH90 blasting hole drill is featured of strong integrity， quick and convenient erection， proper drill mast height to allow completion of the hole in one trip without changing rods （e.g.， the effective height of the drilling mast is slightly greater than the borehole depth）， resistance to large vibration impact force， and adaptability to adverse construction environment. Owing to these characteristics and difficulties， the blasthole drilling mast has been relied on imports since long before， leading to higher drilling cost and longer drilling duration； therefore， research on the substitute for the imported drill mast for the imported DMH90 blasting hole drill was carried out. This paper introduces the development of ZT27-45 blasting hole drill mast for DMH90 blasting hole drill， mainly covering the design points， mast material selection， welding technology， deformation prevention， stress relief and quality inspection. Field practice shows that the manufacturing quality of ZT27-45 drill mast meets the design requirements， and satisfies the needs of blasting hole drilling； thus， it realizes the substitution of import， reduces the cost， shortens the construction period and improves the mechanical properties.