救援井用大直径贯通式潜孔锤及钻头的研制
甘心, 殷琨, 何将福, 殷其雷

Development and test of a large diameter hollow-through DTH air hammer and drill bit used in rescue well
GAN Xin, YIN Kun, HE Jiang-fu, YIN Qi-lei
反循环形成良好