For connection of two sections cable in direct burial, working well or tunnel, the cable metal bushing can be connected directly, and also can be connected across.
用于直埋、工井或隧道内敷设的两段电缆连接，电缆金属护套可直接连接，也可交叉连接。
2
The actual wellbore length from the kelly bushing (KB), derrick floor (DF), foundation or ground level (GL), to a point in the well or bottom of the well.
从方钻杆补心(KB)、钻台(DF)、底座或者地面标高(GL)到井中测量点或者井底的实际井筒长度。
3
The utility model relates to a square bushing for measuring the torsion of a rotary table in the process of drilling Wells, which belongs to an appliance of well drilling equipment.