Method for manufacturing superior 13Cr friction-welded drillrod

Patent metadata

Field	Value
Publication number	US-9988857-B2
Application number	US-201314784446-A
Country	US
Kind code	B2
Filing date	Oct 9, 2013
Priority date	Apr 19, 2013
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

The present invention provides a method for manufacturing a superior 13Cr friction-welded drillrod, the method comprising the following steps: manufacturing a superior 13Cr tube body; manufacturing a superior 13Cr internally threaded coupler and a superior 13Cr externally threaded coupler, respectively; connecting the superior 13Cr internally threaded coupler and the superior 13Cr externally threaded coupler respectively to the two ends of the superior 13Cr tube body by means of frictional butt welding; after heating seam areas to 950° C.-1000° C., cooling same to below 200° C. by ejecting compressed air onto the surfaces of the seam areas, and then cooling the seam areas to room temperature by spraying water; and tempering the seam areas by heating same to 640° C.-700° C. By the present method, a superior 13Cr friction-welded drillrod can be manufactured, which, in the case of the exploration of a gas filed containing a relatively high level of CO2, can be not only used as a drillrod in an earlier stage of nitrogen well-drilling operation, but also used as an oil tube in a later stage of well completion with oil tube.

First claim

The invention claimed is:

1. A method for manufacturing a 13Cr friction-welded drillrod, the method comprising:
a) manufacturing a 13Cr tube body having two opposing ends;
b) manufacturing a 13Cr internally threaded coupler and a 13Cr externally threaded coupler, respectively;
c) connecting the 13Cr internally threaded coupler and the 13Cr externally threaded coupler respectively to the two opposing ends of the 13Cr tube body;
d) heating seam areas between the coupler and tube ends to 950° C.-1000° C.;
e) cooling the heated seam areas to below 200° C.;
f) cooling the seam areas to room temperature; and
g) tempering the seam areas by heating the seam areas to 640° C.-700° C.

2. The method of claim 1 , wherein the 13Cr tube body, 13Cr internally threaded coupler and 13Cr externally threaded coupler comprise 0.01%-0.05 wt % carbon (C), ≤0.5 wt % silicon (Si), 0.2%-1.0 wt % manganese (Mn), 12%-14 wt % chromium (Cr), 1%-3 wt % molybdenum (Mo); 4%-6 wt % nickel (Ni), and a balance of iron (Fe) and other impurities.

3. The method of claim 1 , wherein the step of manufacturing a 13Cr tube body comprises manufacturing a tube body having two opposing ends; thickening the opposing ends of the tube body to obtain a tube body with thickened tube ends; heating the thickened tube body; cooling the thickened tube body; and tempering the thickened tube body.

4. The method of claim 3 , wherein the temperature for thickening the tube ends ranges from 1150° C.-1200° C.

5. The method of claim 3 , wherein the tube body is heated to 950° C.-1000° C.

6. The method of claim 3 , wherein air is used as a cooling medium for cooling the tube body.

7. The method of claim 3 , wherein oil is used as a cooling medium for cooling the tube body.

8. The method of claim 3 , wherein the temperature for tempering the tube body is 600° C.-650° C.

9. The method of claim 1 , wherein the steps of manufacturing a 13Cr internally threaded coupler and a 13Cr externally threaded coupler both comprise manufacturing a blank; forging the blank; heating the forged blank to a temperature ranging from 600° C.-700° C. for a stress-relief annealing; quenching the heated blank; and tempering the quenched blank.

10. The method of claim 9 , wherein the quenching is an oil quenching and the quenching temperature ranges from 950° C.-1000° C.

Assignees

• Baoshan Iron & Steel

Inventors

• Zhao Peng
• Yu Jie
• Dong Changfu

Classifications

• E21B17/042 Primary

  Threaded · CPC title

• C21D6/005

  containing Mn · CPC title

• C21D9/505

  Cooling thereof · CPC title

• F16L15/00

  Screw-threaded joints; Forms of screw-threads for such joints · CPC title

• F16L13/02

  Welded joints · CPC title