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A material which is suitable for equipment in oilfield technology and a process for making the material. The material consist essentially of C, Si, Mn, Cr, Mo, Ni, Cu, N in certain weight percentages, with the balance iron and contaminants due to manufacture. The material is hot formed in a conditio

A material which is suitable for equipment in oilfield technology and a process for making the material. The material consist essentially of C, Si, Mn, Cr, Mo, Ni, Cu, N in certain weight percentages, with the balance iron and contaminants due to manufacture. The material is hot formed in a condition free of nitride precipitates and without precipitated associated phases. After a cooling, it is cold formed in a condition free of ferrites. The material has certain values of relative magnetic permeability, yield strength (R p0.2 ), notched impact strength, fatigue strength under reversed stresses, and fracture appearance transition temperature.

대표청구항 ▼

1. A material suitable for equipment in oilfield technology, consisting essentially of, in percent by weight:with the balance iron and contaminants due to manufacture, which material is hot formed in a condition free of nitride precipitates and without precipitated associated phases and, after a coo

1. A material suitable for equipment in oilfield technology, consisting essentially of, in percent by weight:with the balance iron and contaminants due to manufacture, which material is hot formed in a condition free of nitride precipitates and without precipitated associated phases and, after a cooling, cold formed in a condition free of ferrites, and having a relative magnetic permeability of less than 1.0048 μr, a yield strength (R p0.2 ) of higher than 710 N/mm 2 , a notched impact strength of higher than 60 J, a fatigue strength under reversed stresses of at least ±310 N/mm 2 at N=10 7 load reversal, and a fracture appearance transition temperature (FATT) of below −28° C. 2. The material of claim 1, wherein the C content is ≦0.02 percent by weight. 3. The material of claim 1, wherein the Si content is ≦0.75 percent by weight. 4. The material of claim 1, wherein the Mn content is 1.1 to 2.9 percent by weight. 5. The material of claim 1, wherein the Cr content is 26.1 to 27.9 percent by weight. 6. The material of claim 1, wherein the Mo content is 2.9 to 5.9 percent by weight. 7. The material of claim 1, wherein the Ni content is 27.9 to 32.5 percent by weight. 8. The material of claim 1, wherein the Cu content is 0.98 to 1.45 percent by weight. 9. The material of claim 1, wherein the N content is 0.175 to 0.29 percent by weight. 10. The material of claim 2, wherein the C content is 0.01 to 0.02 percent by weight. 11. The material of claim 3, wherein the Si content is 0.20 to 0.70 percent by weight. 12. The material of claim 4, wherein the Mn content is 2.01 to 2.6 percent by weight. 13. The material of claim 5, wherein the Cr content is 26.5 to 27.5 percent by weight. 14. The material of claim 6, wherein the Mo content is 3.2 to 3.8 percent by weight. 15. The material of claim 7, wherein the Ni content is 30.9 to 32.1 percent by weight. 16. The material of claim 8, wherein the Cu content is 1.0 to 1.4 percent by weight. 17. The material of claim 1, wherein the N content is 0.18 to 0.22 percent by weight. 18. The material of claim 1, containing, in percent by weight: 19. The material of claim 18, containing, in percent by weight: 20. The material of claim 1, wherein the material is hot formed at least 3.6-fold. 21. The material of claim 20, wherein the material is cold formed with a degree of forming of less than 38%. 22. The material of claim 21, wherein the degree of forming is 6 to 19%. 23. The material of claim 21, wherein the material is cold formed at a temperature ranging from 100 to 590° C. 24. The material of claim 22, wherein the material is cold formed at a temperature ranging from 360 to 490° C. 25. The material of claim 19, wherein the material is hot formed at least 3.6-fold and is cold formed with a degree of forming of 6 to 19% at a temperature ranging from 360 to 490° C. 26. The material of claim 1, wherein the material has a pitting potential in a neutral solution at room temperature of at least one of more than 1,100 mVH/1,000 ppm chlorides and more than 1,000 mVH/80,000 ppm chlorides. 27. The material of claim 25, wherein the material has a pitting potential in a neutral solution at room temperature of at least one of more than 1,100 mVH/1,000 ppm chlorides and more than 1,000 mVH/80,000 ppm chlorides. 28. A drilling line component which comprises the material of claim 1. 29. A drilling line component which comprises the material of claim 25. 30. A drill stem which comprises the material of claim 18. 31. A process for making a material suitable for equipment in oilfield technology and having a relative magnetic permeability of less than 1.0048 μr, a yield strength (R p0.2 ) of higher than 710 N/mm 2 , a notched impact strength of higher than 60 J, a fatigue strength under reversed stresses of at least ±310 N/mm 2 at N=10 7 load reversal and a fracture appearance transition temperature (FATT) of below −28° C., said process comprising hot forming a material consisting essentially of, in percent by weight:with the balance iron and contaminants due to manufacture, in a condition free of nitride precipitates and without precipitated associated phases and, after a cooling, cold forming the material in a condition free of ferrites. 32. The process of claim 31, wherein the material contains, in percent by weight: 33. The process of claim 32, wherein the material contains, in percent by weight: 34. The process of claim 32, wherein the material is hot formed at least 3.6-fold. 35. The process of claim 34, wherein the material is cold formed with a degree of forming of less than 38%. 36. The process of claim 35, wherein the degree of forming is 6 to 19%. 37. The process of claim 35, wherein the material is cold formed at a temperature ranging from 100 to 590° C. 38. The process of claim 36, wherein the material is cold formed at a temperature ranging from 360 to 490° C. 39. The process of claim 33, wherein the material is hot formed at least 3.6-fold and is cold formed with a degree of forming of 6 to 19% at a temperature ranging from 360 to 490° C. 40. The process of claim 32, wherein the material suitable for equipment in oilfield technology is a drill line component.