CPC Subgroup
E21B 27/02 Dump bailers, i.e. containers for depositing substances, e.g. cement or acids
Full Title
Containers for collecting or depositing substances in boreholes or wells, e.g. bailers, for collecting mud or sand; Drill bits with means for collecting substances, e.g. valve drill bits > Dump bailers, i.e. containers for depositing substances, e.g. cement or acids