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这种炮孔填塞塞可在各种深度上填塞炮孔。塞的外侧为橡胶壳,壳内装有塑料套,套中则充填有起泡材料。塞长为0.46米。当
This bore plug can fill the borehole in various depths. The outside of the plug is a rubber shell, a plastic sleeve is arranged in the shell, and a foaming material is filled in the sleeve. Cypriot length of 0.46 meters. when