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由重庆煤炭科学研究所和四川省松藻矿务局共同研制的HB4—160型液压支架,于一九七八年十月至一九七九年十二月在松藻矿
The HB4-160 hydraulic support, jointly developed by the Chongqing Coal Research Institute and Sichuan Songzao Mining Bureau, operated in Songzao Mine from October 1978 to December 1979