Drilling substructure transfer system

A method for placing an oil or gas drilling apparatus on a fixed offshore platform, comprising the steps of:

• a. providing the drilling apparatus on a jack-up rig having one or more legs and a barge portion;
• b. jacking down the legs until they engage water bottom, raising the barge portion out of the water, thereby supporting the jack-up rig firmly on the water bottom;
• c. elevating the jack-up rig to a level substantially equal to the level of the fixed platform;
• and
• d. sliding the drilling apparatus from the jack-up rig to the fixed platform.

The method of providing an oil or gas drilling apparatus on a fixed offshore platform comprising the steps of:

• a. providing a jack-up rig including a structure which comprises:
• i. a rigid, moveable substructure for supporting the drilling apparatus,
• ii. a structural skid mat, and
• iii. a rigid, moveable structural bridge connectable at one end portion to said skid mat and at the other end portion to said substructure;
• b. placing the substructure, skid mat, and bridge on a conventional type jack-up rig;
• c. locating the jack-up rig proximately to the fixed platform;
• d. connecting the bridge at one end portion to the substructure and its other end portion to the skid mat, the connection made so that the bottom surface elevation of the skid mat and substructure are substantially equal;
• e. elevating the jack-up rig to an elevation where the surface of the jack-up rig is substantially at equal elevation to the furface of the fixed platform;
• f. sliding the skid mat and bridge from the jack-up rig to the fixed platform a distance which aligns the end portion of the bridge connected to the substructure with the edge of the jack-up rig nearest the fixed platform;
• g. parting the connection between the substructure and the bridge;
• h. elevating the jack-up rig to an elevation where the deck of the jack-up rig is substantially at the same elevation with the upper surface of the bridge;
• i. connecting the end portion of the bridge nearest the substructure to the jack-up rig;
• and
• j. sliding the substructure and drilling apparatus thereon from the jack-up rig across the bridge onto the skid mat.

The method of placing an oil or gas drilling apparatus on a fixed offshore platform comprising the steps of:

• a. providing a jack-up rig including a structure which comprises:
• i. a skid mat;
• ii. a structural bridge connectable at one end portion to said jack-up rig and at the other end portion to said substructure;
• b. placing the drilling apparatus on the jack-up rig;
• c. elevating the surface of the jack-up rig to an elevation substantially equal the elevation of the surface of the fixed platform;
• d. connecting the structural bridge at one end portion to the jack-up rig and at the other end portion to the fixed platform;
• and
• e. transferring the drilling apparatus across the bridge from the jack-up rig to the fixed platform.