Oil well drill with hollow rod string - has electrical plug and contacts joined when rods join giving axial or radial play on rod ends

摘要

The oil well drill with hollow string supplies mud to the hole face and has the components of an electrical plug connector inside the string at the ends of the rods being connected. Teh contacts for the plug are concentric and axially spaced within the ends of the hollow rods so that contact is made when the rods are joined. Spider carriers are provided to locate and hold concentrically both the contacts and the plug parts but at the same time leave a passage for the mud to flow down through the string of hollow rods. Pref. the components or the contacts should have axial or radial play as mounted on their respective rods.