EP0070764A1 - Amagnetic drill collar made from precipitation-hardenable austenitic steels - Google Patents

Amagnetic drill collar made from precipitation-hardenable austenitic steels Download PDF

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Publication number
EP0070764A1
EP0070764A1 EP82401283A EP82401283A EP0070764A1 EP 0070764 A1 EP0070764 A1 EP 0070764A1 EP 82401283 A EP82401283 A EP 82401283A EP 82401283 A EP82401283 A EP 82401283A EP 0070764 A1 EP0070764 A1 EP 0070764A1
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Prior art keywords
precipitation
amagnetic
steel
drill collars
drill
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EP82401283A
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German (de)
French (fr)
Inventor
André Desestret
Roger Mayoud
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Creusot Loire SA
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Creusot Loire SA
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese

Definitions

  • the present invention relates to a new product constituted by a new species of drill collars which can be used for drilling oil or natural gas wells.
  • the drilling of oil or natural gas wells is generally carried out using a device made up of tubular steel elements, called “rods”, arranged one after the other. Their assembly forms a “drill string”, at the end of which is the drill bit, and is possibly driven by a rotational movement.
  • the elements located at the front of the train are more massive and serve, in particular, to ensure a permanent effort on the drill bit. they are called “drill sticks". Their outside diameter can reach approximately 250 millimeters and their length approximately 10 meters. These drill rods have a bore whose diameter can, for example, be of the order of 60 mm and they are assembled together by screwing.
  • Sludge is injected inside the drill string to provide lubrication at the drill bit level and entrain the debris formed.
  • the mud thus loaded with debris rises to the surface through the space which exists between the exterior wall of the train and the wall of the borehole.
  • the drill rods are normally made of low-alloy structural steel, of the 42 CD 4 type for example, that is to say 0.42% carbon and 1% chromium, with a little molybdenum.
  • the head drill collars must be made of non-magnetic steel.
  • the orientation of the train is controlled from magnetic compasses (compasses), the indications of which must absolutely not be disturbed by the presence of ferro-magnetic materials.
  • non-magnetic drill rods are obtained, in a very general way, by cold working (hot or cold) of stainless steels of various compositions, the balancing of the alphagenic and gammagenic elements and the structural stability are such that 'there is no presence of ferrite nor possibility of formation of martensite p ⁇ .
  • Composition 1 is a composition of Composition 1:
  • Composition 2 is a composition of Composition 2:
  • the latter are in contact with the sludge which is injected into the drilling train and which contains large quantities of chlorides (several hundred grams per liter).
  • chlorides Cr 2 Mg, Cl 2 Ca, ClNa, ClK
  • the temperature at the level of the drill rods can be of the order of 100 ° C.
  • constraints residual constraints and working constraints
  • the object of the present invention is to be able to have non-magnetic drill collars having excellent resistance to corrosion under stress as it exists in oil drilling, using austenitic steels with structural hardening, chosen from those which have have been described in patent No. 70-20479.
  • the required tensile strength and yield strength are very easily achieved after water hardening (e.g. from 1150 ° C) and structural hardening (e.g. 10 hours at 660 ° C), resulting of a precipitation of vanadium carbides.
  • the magnetic permeability is less than 1.010.
  • a significantly higher carbon content should be used, greater than 0.6% or 0.7% (instead of 0.25% to 0.45% in the invention), which would lead to marked degradation the ability to machine metal.
  • the steel grades according to the invention have, compared to the grades currently used, the main advantage of very much higher resistance to corrosion under tension under the conditions of use of the drill collars.
  • the invention makes available to the petroleum industry drill rods with the required mechanical properties associated for the first time with excellent resistance to corrosion under stress.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Earth Drilling (AREA)

Abstract

A new kind of drill collars which can be employed for drilling oil or natural gas wells. The amagnetic drill collars exhibiting the usual mechanical properties required in drill collars are characterised in that they are made of austenitic steel with structural hardening obtained by precipitation of vanadium carbides, this steel having a composition lying in the range: %C = 0.25 to 0.45, %V = 1 to 2.5, %Mn = 15 to 30, %Cr: = less than 10, and in that they have an excellent stress corrosion resistance under the specific conditions of oil drilling operations.

Description

La présente invention concerne un produit nouveau constitué par une nouvelle espèce de masses-tiges utilisables pour le forage des puits de pétrole ou de gaz naturel.The present invention relates to a new product constituted by a new species of drill collars which can be used for drilling oil or natural gas wells.

Le forage des puits de pétrole ou de gaz naturel est généralement effectué à l'aide d'un dispositif constitué d'éléments tubulaires en acier, appelés "tiges", disposés les uns à la suite des autres. Leur ensemble forme un "train de tiges", au bout duquel se trouve le trépan, et est éventuellement animé d'un mouvement de rotation.The drilling of oil or natural gas wells is generally carried out using a device made up of tubular steel elements, called "rods", arranged one after the other. Their assembly forms a "drill string", at the end of which is the drill bit, and is possibly driven by a rotational movement.

Les éléments situés à l'avant du train sont plus massifs et servent, en particulier, à assurer un effort permanent sur le trépan. on les appelle "masses-tiges". Leur diamètre extérieur peut atteindre 250 millimètres environ et leur longueur 10 mètres environ. Ces masses-tiges possèdent un alésage dont le diamètre peut, par exemple, être de l'ordre de 60 mm et elles sont assemblées entre elles par vissage.The elements located at the front of the train are more massive and serve, in particular, to ensure a permanent effort on the drill bit. they are called "drill sticks". Their outside diameter can reach approximately 250 millimeters and their length approximately 10 meters. These drill rods have a bore whose diameter can, for example, be of the order of 60 mm and they are assembled together by screwing.

Une boue est injectée à l'intérieur du train de tiges pour assurer une lubrification au niveau du trépan et entrainer les débris formés. La boue ainsi chargée de débris remonte à la surface par l'espace qui existe entre la paroi extérieure du train et la paroi du forage.Sludge is injected inside the drill string to provide lubrication at the drill bit level and entrain the debris formed. The mud thus loaded with debris rises to the surface through the space which exists between the exterior wall of the train and the wall of the borehole.

Les masses-tiges sont normalement réalisées en acier de construction faiblement allié, du type 42 CD 4 par exemple, c'est-à-dire à 0,42 % de carbone et 1 % de chrome, avec un peu de molybdène. Toutefois, dans le cas des forages déviés, les masses-tiges de tête doivent être réalisées en acier amagnétique. En effet, dans ce cas, l'orientation du train est pilotée à partir de compas magnétiques (boussoles), dont les indications ne doivent absolument pas être perturbées par la présence de matériaux ferro-magnétiques.The drill rods are normally made of low-alloy structural steel, of the 42 CD 4 type for example, that is to say 0.42% carbon and 1% chromium, with a little molybdenum. However, in the case of deviated drilling, the head drill collars must be made of non-magnetic steel. In this case, the orientation of the train is controlled from magnetic compasses (compasses), the indications of which must absolutely not be disturbed by the presence of ferro-magnetic materials.

Les caractéristiques mécaniques visées sont, par exemple, les suivantes :

  • Rm ≥ 88 daN/mm = 90 Kg/mm2 . (Rm = Résistance à la traction) R 0,002 ≥ 73,5 daN/mm2 = 75 Kg/mm2. (R0,002 = Contrainte provoquant un allongement résiduel de 0,2 %). La perméabilité magnétique doit être inférieure à 1,010.
The mechanical characteristics targeted are, for example, the following:
  • Rm ≥ 88 daN / mm = 90 Kg / mm 2 . (Rm = Tensile strength) R 0.002 ≥ 73.5 daN / mm 2 = 75 Kg / mm2. (R0.002 = Stress causing a residual elongation of 0.2%). The magnetic permeability must be less than 1.010.

Actuellement, les masses-tiges amagnétiques sont obtenues, d'une façon très générale, par écrouissage (à chaud ou à froid) d'aciers inoxydables de diverses compositions, dont l'équilibrage des éléments alphagènes et gammagènes et la stabilité structurale sont tels qu'il n'y a pas présence de ferrite ni possibilité de formation de martensite p< .Currently, non-magnetic drill rods are obtained, in a very general way, by cold working (hot or cold) of stainless steels of various compositions, the balancing of the alphagenic and gammagenic elements and the structural stability are such that 'there is no presence of ferrite nor possibility of formation of martensite p <.

On peut citer, à titre d'exemple, les deux compositions suivantes d'aciers utilisés pour des masses-tiges de type connu :By way of example, mention may be made of the following two compositions of steels used for drill collars of known type:

Composition 1 :Composition 1:

Figure imgb0001
Figure imgb0001

Composition 2 :Composition 2:

Figure imgb0002
Figure imgb0002

Toutefois, les nuances de ces types connus présentent l'inconvénient d'être sensibles à la corrosion sous tension dans les conditions d'utilisation des masses-tiges amagnétiques.However, the grades of these known types have the drawback of being sensitive to stress corrosion under the conditions of use of non-magnetic drill collars.

En effet, ces dernières sont en contact avec les boues que l'on injecte dans le train de forage et qui contiennent de grandes quantités de chlorures (plusieurs centaines de gramme par litre). Ces chlorures (Cl2Mg, Cl2Ca, ClNa, ClK) sont ajoutés intentionnellement pour obtenir un milieu "sensiblement en équilibre" avec les couches salines que l'on rencnntre très fréquemment en cours de forage. On évite ainsi les risques d'effondrement par dissolution de ces couches. Par ailleurs, la température au niveau des masses-tiges peut être de l'ordre de 100°C.In fact, the latter are in contact with the sludge which is injected into the drilling train and which contains large quantities of chlorides (several hundred grams per liter). These chlorides (Cl 2 Mg, Cl 2 Ca, ClNa, ClK) are intentionally added to obtain a medium "substantially in equilibrium" with the salt layers which are encountered very frequently during drilling. This avoids the risk of collapse by dissolution of these layers. Furthermore, the temperature at the level of the drill rods can be of the order of 100 ° C.

Enfin des contraintes (contraintes résiduelles et contraintes de travail) peuvent apparaître, dans l'alésage en particulier.Finally, constraints (residual constraints and working constraints) may appear, in the bore in particular.

En pratique, des fissurations importantes des pièces, partant de l'alésage, peuvent être observées après seulement quelques centaines d'heures de fonctionnement.In practice, significant cracks in the parts, starting from the bore, can be observed after only a few hundred hours of operation.

Le but de la présente invention est de pouvoir disposer de masses-tiges amagnétiques présentant une excellente résistance à la corrosion sous tension telle qu'elle existe dans les forages pétroliers, en faisant appel à des aciers austénitiques à durcissement structural, choisis parmi ceux qui ont été décrits dans le brevet n° 70-20479.The object of the present invention is to be able to have non-magnetic drill collars having excellent resistance to corrosion under stress as it exists in oil drilling, using austenitic steels with structural hardening, chosen from those which have have been described in patent No. 70-20479.

A cet effet, la présente invention a pour objet des masses-tiges amagnétiques pour le forage de puits de pétrole ou de gaz naturel, caractérisées en ce qu'elles sont réalisées en acier austénitique à durcissement structural, présentant une composition comprise dans le domaine suivant :

  • C% = 0,25 à 0,45 ; V % = 1 à 2,5 ; Mn % = 15 à 30; Cr % : moins de 10.
To this end, the present invention relates to non-magnetic drill rods for drilling oil or natural gas wells, characterized in that they are made of austenitic steel with structural hardening, having a composition included in the following field :
  • C% = 0.25-0.45; V% = 1 to 2.5; Mn% = 15 to 30; Cr%: less than 10.

Plus avantageusement encore, la composition de l'acier est choisie dans le domaine suivant :

  • C % = 0,34 à 0,36 ; V % = 1,7 à 1,9 ; Mn % = 20 à 25 ; Cr % : moins de 1.
Even more advantageously, the composition of the steel is chosen in the following field:
  • C% = 0.34 to 0.36; V% = 1.7 to 1.9; Mn% = 20 to 25; Cr%: less than 1.

La résistance à la traction et la limite d'élasticité requises sont très facilement atteintes après une hypertrempe à l'eau (par exemple à partir de 1150°C) et un durcissement structural (par exemple : 10 heures à 660°C), résultant d'une précipitation de carbures de vanadium.The required tensile strength and yield strength are very easily achieved after water hardening (e.g. from 1150 ° C) and structural hardening (e.g. 10 hours at 660 ° C), resulting of a precipitation of vanadium carbides.

La perméabilité magnétique est inférieure à 1,010.The magnetic permeability is less than 1.010.

Le durcissement structural de ces aciers, encore un peu faible pour une teneur en vanadium comprise entre 0,5 % et 1 %, se trouve nettement amélioré par une plus forte teneur en vanadium, comprise entre 1 % et 2,5 %. L'optimum se situe entre 1,7 % et 1,9 % de vanadium.The structural hardening of these steels, still a little weak for a vanadium content of between 0.5% and 1%, is significantly improved by a higher vanadium content, between 1% and 2.5%. The optimum is between 1.7% and 1.9% vanadium.

Plus précisément, pour une teneur en vanadium inférieure à 1 %, si l'on voulait maintenir des caractéristiques mécaniques élevées, par exemple Rm au moins égale à 88 daN/mm2 de R0,002 au moins égale à 73,5 daN/mm2, il faudrait utiliser une teneur en carbone nettement plus élevée, supérieure à 0,6 % ou à 0,7 % (au lieu de 0,25 % à 0,45 % dans l'invention), ce qui conduirait à une dégradation marquée de l'aptitude à l'usinage du métal.More precisely, for a vanadium content of less than 1%, if it was desired to maintain high mechanical characteristics, for example Rm at least equal to 88 daN / mm 2 of R 0.002 at least equal to 73.5 daN / mm 2 , a significantly higher carbon content should be used, greater than 0.6% or 0.7% (instead of 0.25% to 0.45% in the invention), which would lead to marked degradation the ability to machine metal.

Or, cette aptitude à l'usinage doit absolument être préservée pour la fabrication des masses-tiges amagnétiques, en particulier pour le forage de l'alésage sur une longueur de 9 mètres environ, qui est une opération très délicate.However, this aptitude for machining must absolutely be preserved for the manufacture of non-magnetic drill collars, in particular for drilling the bore over a length of approximately 9 meters, which is a very delicate operation.

Les nuances d'acier selon l'invention présentent, par rapport aux nuances actuellement utilisées, l'avantage principal d'une résistance à la corrosion sous tensiontrès nettement supérieure dans les conditions d'utilisation des masses-tiges.The steel grades according to the invention have, compared to the grades currently used, the main advantage of very much higher resistance to corrosion under tension under the conditions of use of the drill collars.

C'est ainsi que des essais de corrosion sous tension effectués au laboratoire sous charge constante ( δ= ½ R0,002) dans une solution aérée, portée à 110°C et contenant 310g de C12Mg et 110 g de ClNa par litre (conditions de concentration pouvant être rencontrées en pratique pour les solutions destinées à la fabrication des boues de forage) ont donné les résultats suivants, sur éprouvettes de 2 millimètres de diamètre :

  • Composition 1 (écrouie), de type connu :
    • Rupture des éprouvettes après 10 heures environ de maintien sous charge.
  • Composition 2 (écrouie), de type connu :
    • Rupture des éprouvettes après 100 heures environ de maintien sous charge.
  • Nuance à durcissement structural, selon ltinvention :
    • Aucune rupture après 1000 heures de maintien sous charge.
This is how stress corrosion tests carried out in the laboratory under constant load (δ = ½ R 0.002 ) in an aerated solution, brought to 110 ° C and containing 310g of C1 2 Mg and 110 g of ClNa per liter (conditions concentration which may be encountered in practice for solutions intended for the manufacture of drilling muds) gave the following results, on test pieces of 2 millimeters in diameter:
  • Composition 1 (work hardened), of known type:
    • Rupture of the test pieces after approximately 10 hours of maintenance under load.
  • Composition 2 (work hardened), of known type:
    • Breakage of the test pieces after approximately 100 hours of maintenance under load.
  • Structural hardening grade, according to t invention:
    • No break after 1000 hours of maintenance under load.

Ainsi, l'invention met à la disposition de l'industrie pétrolière des masses-tiges présentant les propriétés mécaniques requises associées pour la première fois à une excellente résistance à la corrosion sous tension.Thus, the invention makes available to the petroleum industry drill rods with the required mechanical properties associated for the first time with excellent resistance to corrosion under stress.

Il est bien entendu que l'on peut, sans sortir du cadre de l'invention, imaginer des variantes et perfectionnements de détails.It is understood that one can, without departing from the scope of the invention, imagine variants and improvements of details.

Claims (2)

1.- Masses tiges amagnétiques pour le forage de puits de pétrole ou de gaz naturel, présentant les propriétés mécaniques usuelles requises pour les masses-tiges, caractérisées en ce qu'elles sont réalisées en acier austénitique à durcissement structural obtenu par précipitation de carbures de vanadium, cet acier ayant une composition comprise dans le domaine suivant : C % = 0,25 à 0,45 ; V % = 1 à 2,5 % , Mn % = 15 à 30 ; Cr % : moins de 10, et en ce qu'elles présentent une excellente résistance à la corrosion sous tension. 1.- Non-magnetic drill rods for drilling oil or natural gas wells, having the usual mechanical properties required for drill rods, characterized in that they are made of austenitic steel with structural hardening obtained by precipitation of carbides of vanadium, this steel having a composition included in the following field: C% = 0.25-0.45; V% = 1 to 2.5%, Mn% = 15 to 30; Cr%: less than 10, and in that they have excellent resistance to corrosion under stress. 2.- Masses-tiges amagnétiques selon la revendication 1, caractérisées en ce qu'elles sont réalisées en acier austénitique à durcissement structural, présentant une composition comprise dans le domaine suivant : C % = 0,34 à 0,36 ; V % = 1,7 à 1,9 ; Mn % = 20 à 25 ; Cr % : moins de 1. 2.- Non-magnetic drill rods according to claim 1, characterized in that they are made of austenitic steel with structural hardening, having a composition included in the following field: C% = 0.34 to 0.36; V% = 1.7 to 1.9; Mn% = 20 to 25; Cr % : less than 1.
EP82401283A 1981-07-10 1982-07-07 Amagnetic drill collar made from precipitation-hardenable austenitic steels Ceased EP0070764A1 (en)

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FR8113597 1981-07-10
FR8113597A FR2509365A1 (en) 1981-07-10 1981-07-10 AMAGNETIC ROD SHAFTS IN AUSTENITIC STEEL WITH STRUCTURAL CURING

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2205854A (en) * 1987-06-18 1988-12-21 Agency Ind Science Techn Erosion resistant alloys
EP0354958A4 (en) * 1987-03-05 1990-01-16 Terumo Corp Apparatus for measuring data of living body.

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104109811B (en) * 2014-07-03 2016-06-29 武汉钢铁(集团)公司 Mn-Cr-V system superhigh intensity nonmagnetic steel and production method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR713445A (en) * 1930-12-11 1931-10-27 Krupp Ag Non-magnetic steel
DE963782C (en) * 1943-06-16 1957-05-16 Phoenix Rheinrohr Ag Vereinigt Use of high-alloy manganese steels as a material for components that come into contact with hot carbon oxide gas
FR1259186A (en) * 1959-06-04 1961-04-21 Schoeller Bleckmann Stahlwerke Use of non-magnetizable austenitic alloy steels for weight bars
AT243296B (en) * 1962-02-12 1965-11-10 Schoeller Bleckmann Stahlwerke Austenitic chromium-manganese-nitrogen steels for the manufacture of objects resistant to stress corrosion cracking
GB1127147A (en) * 1965-07-26 1968-09-11 Gen Electric Improvements in alloy steels
FR2095643A5 (en) * 1970-06-05 1972-02-11 Deutsche Edelstahlwerke Ag
DE2457719A1 (en) * 1974-12-06 1976-06-16 Krupp Ag Huettenwerke Age hardenable austenitic manganese steel - is for wheel of rail vehicle which incorporates integral braking disc

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR713445A (en) * 1930-12-11 1931-10-27 Krupp Ag Non-magnetic steel
DE963782C (en) * 1943-06-16 1957-05-16 Phoenix Rheinrohr Ag Vereinigt Use of high-alloy manganese steels as a material for components that come into contact with hot carbon oxide gas
FR1259186A (en) * 1959-06-04 1961-04-21 Schoeller Bleckmann Stahlwerke Use of non-magnetizable austenitic alloy steels for weight bars
AT243296B (en) * 1962-02-12 1965-11-10 Schoeller Bleckmann Stahlwerke Austenitic chromium-manganese-nitrogen steels for the manufacture of objects resistant to stress corrosion cracking
GB1127147A (en) * 1965-07-26 1968-09-11 Gen Electric Improvements in alloy steels
FR2095643A5 (en) * 1970-06-05 1972-02-11 Deutsche Edelstahlwerke Ag
DE2457719A1 (en) * 1974-12-06 1976-06-16 Krupp Ag Huettenwerke Age hardenable austenitic manganese steel - is for wheel of rail vehicle which incorporates integral braking disc

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0354958A4 (en) * 1987-03-05 1990-01-16 Terumo Corp Apparatus for measuring data of living body.
EP0354958A1 (en) * 1987-03-05 1990-02-21 Terumo Kabushiki Kaisha Apparatus for measuring data of living body
GB2205854A (en) * 1987-06-18 1988-12-21 Agency Ind Science Techn Erosion resistant alloys
GB2205854B (en) * 1987-06-18 1991-02-27 Agency Ind Science Techn Erosion resistant alloys

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