Metal seal weld-on connector for conductor casing

An improved weld-on connector (1) for conductor casing comprising:

• a circular box member (2) having internal threads at tapered inner surface;
• and
• a circular pin member (3) having matching external threads at tapered outer surface fastened on the internal threads of the box member (2);
• wherein,
• said weld-on connector (1) provides a first sealing comprising metal-to-metal seal over a tapered surface near a free end (8) of the pin member (3) to protect the internal threads and the external threads of the connector assembly (1) from fluid flowing inside the pin member (3);
• said weld-on connector (1) provides a second sealing provided by an O-ring (4) located in a groove (5) in the pin member (3) to protect the internal threads and the external threads from fluids flowing outside the connector assembly (1);
• said weld-on connector (1) provides a face-to-face sealing at two places in connector (1) wherein a face-to-face sealing (12b) is effected by providing a matching seat (14) in the box member (2) that mates with a protrusion (13) in the pin member (3) and other face-to-face sealing is effected over load flank surface (12a) of the internal threads and the external threads of connector (1);
• and
• said internal threads and the external threads are pre-loaded for fatigue and are multi-start to achieve full make up in 1 to 2 rotations.