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安徽省地质局327队在7级凝灰砂岩中钻进，创造了一种稜形飞机式钻头，单位小时进尺最高达5.64米，平均达4米左右（见表）。还曾创造台班进尺17.78米的新成绩。
The 327 team of Anhui Bureau of Geology drilled in Grade 7 tuffaceous sandstone and created a prismatic aircraft drill with unit footage of up to 5.64 meters per hour and an average of about 4 meters (see table). Also created a new grade of 17.78 meters into the bench class.