Drilling substructure transfer system

• US 4,103,503 A
• Filed: 12/21/1976
• Issued: 08/01/1978
• Est. Priority Date: 12/21/1976
• Status: Expired due to Term

• Current Assignee: Rowan Companies Incorporated
• Original Assignee: Dixilyn International Incorporated
• Inventors: Smith, Marvin L.
• Primary Examiner(s): Taylor, Dennis L.
• Application Number:
  US05/753,092
• Time in Patent Office: 588 Days
• Field of Search: 61/86-94, 61/97-102, 114/258, 114/264, 214/38 BA
• US Class Current: 405/196
• CPC Class Codes: E02B 17/021 with relative movement between supporting construction and platform
• CPC Class Codes: E02B 17/027 steel structures E02B17/021 takes precedence
• CPC Class Codes: E02B 2017/0047 using a barge
• CPC Class Codes: E02B 2017/006 with lattice style supporting legs
• CPC Class Codes: E02B 2017/0082 Spudcans, skirts or extended feet

Abstract

An apparatus and method for providing a drilling rig substructure on a fixed platform which includes the transfer of the drilling rig substructure from a movable jack-up type rig to an adjacent, fixed oil platform. The method provided utilizes a conventional type jack-up rig which includes a barge mounted telescopically on a plurality of structural support legs. A substructure, containing the entire apparatus for drilling or reworking an oil or gas well, connected to an associated bridge and skid mat, are connectably housed on the barge portion of the jack-up rig. The barge is elevated to the approximate level of the fixed platform to which the drilling apparatus is to be transferred. The substructure, bridge and skid mat are slid from the barge towards the surface of the fixed platform to a degree which leaves the substructure and associated drilling apparatus on the barge portion of the jack-up rig. The substructure is disconnected from the skid mat and bridge, and a second elevational increase elevates the substructure to a level where it can be slid from the barge across the bridge (connected now to the barge portion of the jack-up rig) onto the skid mat, now located on the fixed platform.

The apparatus of the present invention includes a substructure capable of housing and supporting a typical oil drilling apparatus, a connecting bridge for spanning the gap between the jack-up rig and the fixed platform during the skidding operation, and a structural skid mat. The mat is so dimensioned that the substructure and associated drilling equipment can be adjusted as needed within allowable tolerances to rework or drill new wells on existing fixed platforms which initially are without the necessary drilling facilities.

Claims

1. An apparatus for transferring an oil or gas drilling apparatus from a jack-up rig to a fixed platform which apparatus comprises:

a substructure capable of supporting a drilling apparatus;

b. a structural bridge connectable to said substructure;

c. a structural skid mat connectable to the opposite end portion of said structural bridge from the portion of said bridge connectable to said substructure, said substructure, said bridge, and said skid mat connectable in a manner which allows said substructure, said bridge and said skid mat to be skidded on the surface of the jack-up rig to a position placing said skid mat on the fixed platform, said substructure remaining on said jack-up rig; and

;

d. connection means on said bridge for connecting said bridge to a side deck portion of the jack-up rig, the top portion of said bridge being substantially level with the top portions of said skid mat and said jack-up rig, said bridge and said skid mat when so connected being capable of supporting said substructure with a contained drilling apparatus thereon.

2. The apparatus as claimed in claim 1, wherein said substructure is additionally comprised of means for skidding said substructure along said jack-up rig, said bridge, and said skid mat.

3. The apparatus as claimed in claim 2, wherein said skidding means is at least one hydraulic jack attached to said substructure, said jack having hook means for gripping at least a portion of said bridge, and said skid mat.

4. The apparatus as described in claim 3 wherein said skid mat and said bridge are provided with upper slotted means for receivably connecting said jack to said slots at said hook means.

5. The apparatus as described in claim 4, wherein there is provided on the jack-up rig, means for connecting one end portion of said bridge to said jack-up rig, said connection positioning said bridge horizontally at an elevation substantially equal to that of the deck portion of said skid mat, the other end portion of said bridge connectable to said skid mat at a position which places the elevation of said bridge substantially equal to the other surface of said skid mat.

6. 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.

7. The method of claim 6, wherein there is further included between steps b and c the step of connecting a bridge between the jack-up rig and the fixed platform.

8. 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.

9. 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.

10. The method of claim 9 further comprising the step between steps "b" and "c" of supporting the jack-up rig firmly on the water bottom.

11. The method of claim 9 in which a movable substructure is provided in step "a" for supporting the drilling apparatus, and in step "e" the drilling apparatus is transferred from the jack-up rig to the fixed platform by sliding the substructure and the supported drilling apparatus from the jack-up rig across the bridge to the fixed platform.

12. The method of claim 11, further comprising the steps between steps "c" and "d" of:

-connecting the structural bridge at one end portion to the substructure and at its other end portion to the skid mat;

-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; and

-the connection between the substructure and the bridge.