PERFORATING GUN TUBE AND PERFORATING GUN

Abstract

The present invention relates to a perforating gun tube, characterized in that the tube is made of a steel alloy comprising, in addition to iron, the following alloying elements, expressed in mass percent:

TABLE-US-00001 C 0.12-0.22% Si 0.3-1.0% Mn 1.0 - 4% Cr 0.5 - 2% Mo 0.1 -1%, V 0.05 -0.2% Ti 0.02 - 0.1% and B 0.001 - 0.01%

and impurities due to melting, and that the tube has a yield strength, R.sub.P0,2 , in the range of 750 to 1100 MPa. In addition, a perforating gun having such a perforating gun tube is described.

Claims

1. A perforating gun tube, characterized in that the tube is made of a steel alloy comprising, in addition to iron, the following alloying elements, expressed in percent by mass: TABLE-US-00013 C 0.12 - 0.22% Si 0.3 - 1.0% Mn 1.0 - 4% Cr 0.5 - 2% Mo 0.1 - 1%, V 0.05 -0.2% Ti 0.02 - 0.1% and B 0.001 - 0.01% and impurities due to melting, and that the tube has a yield strength, RP0,2 , in the range from 750 to 1100 MPa.

2. The perforating gun tube of claim 1, wherein the tube has an air-hardened bainitic microstructure.

3. The perforating gun tube of claim 1, wherein the tube has a yield strength, RP0,2 , in the range of 850 to 1050 MPa.

4. The perforating gun tube of claim 1, wherein the tube has a tensile strength Rm of at least 1100 MPa preferably up to a maximum of 1400 MPa.

5. The perforating gun tube of claim 1, wherein the tube has a yield strength ratio Re /Rm of less than 0.9, preferably less than 0.87, more preferably 0.8 or 0.7.

6. The perforating gun tube according to claim 1, wherein the tube has a breaking elongation of more than 10%, preferably more than 13%, more preferably more than 16%.

7. The perforating gun tube of claim 1, wherein the tube has been subjected to at least one straightening step after manufacture.

8. The perforating gun tube of claim 1, wherein the tube has at least one predetermined breaking point in the form of a reduced wall thickness.

9. The perforating gun tube according to claim 1, wherein the carbon content is in the range of 0.15-0.22%, in particular 0.17-0.20%.

10. The perforating gun tube according to claim 1, wherein the silicon content is in the range of 0.4 to 0.85%, preferably in the range of 0.5 to 0.7%.

11. The perforating gun tube according to claim 1, wherein the manganese content is in the range from 1.4 to 3.0%, preferably in the range from 1.6 to 2.5%, more preferably between 2.0 to 2.3%.

12. The perforating gun tube according to claim 1, wherein the chromium content is in the range of from 0.5 - 1.8%, preferably in the range of from 1.0 to 1.8%, more preferably from 1.3 to 1.5%.

13. The perforating gun tube according to claim 1, wherein the molybdenum content is in the range of 0.14-0.7%, preferably in the range of 0.17-0.3%.

14. The perforating gun tube according to claim 1, wherein the vanadium content is in the range of 0.05-0.15%, preferably in the range of 0.06-0.15%.

15. The perforating gun tube according to claim 1, wherein the titanium content is in the range of 0.03-0.1%, preferably in the range of 0.04-0.08%.

16. The perforating gun tube according to claim 1, wherein the boron content is in the range of 0.001 - 0.006%, preferably in the range of 0.0015 to 0.0025%.

17. A perforating gun barrel according to claim 1, characterized in that the steel alloy consists of, expressed in mass percent: TABLE-US-00014 C 0.17 - 0.20% Mn 1.7 - 2.2% Si 0.5 - 0.7% Cr 0.6-1.4% V 0.05 - 010% B 0.0010 - 0.0030% Ti 0.03 - 0.08% Mo 0.1-0.2% remainder iron and impurities due to melting.

18. A perforating gun comprising a perforating gun tube, characterized in that the tube is made of a steel alloy comprising, in addition to iron, the following alloying elements, expressed in percent by mass: TABLE-US-00015 C 0.12 - 0.22% Si 0.3 - 1.0% Mn 1.0 - 4% Cr 0.5 - 2% Mo 0.1 - 1%, V 0.05 -0.2% Ti 0.02 - 0.1% and B 0.001 - 0.01% and impurities due to melting, and that the tube has a yield strength, RP0,2 , in the range from 750 to 1100 MPa.

19. The perforating gun of claim 18, wherein the perforating gun tube is the outer tube of the perforating gun tube.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will now be further explained with reference to the accompanying drawings. Showing:

[0038] FIG. 1: a schematic representation of a perforating gun with a perforating gun tube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] FIG. 1 schematically shows an embodiment of the perforating gun 1. The perforating gun 1 comprises a perforating gun tube 10, which may also be referred to as a hollow carrier. Preferably, the perforating gun tube 10 constitutes a seamless tubular element. Locally confined regions 100 having a reduced wall thickness are introduced in the perforating gun tube 10. The locally confined regions 100 each have a circular area. The regions 100 are distributed along the length of the perforating gun tube 10. An ignition unit 11 with ignition charges is inserted in the perforating gun tube 10. By means of the ignition unit 11, the explosive material of the ignition charge is ignited and thereby, on the one hand, the regions 100 of the perforating gun tube 10 are opened and, on the other hand, the surrounding material, for example rock, is perforated.

TABLE-US-00012 List of reference signs 1 Perforating gun 10 Perforating gun tube 100 Region of lower wall thickness 11 Ingnition unit