JPH06221475A - Tightening method for oil well pipe thread joint - Google Patents

Tightening method for oil well pipe thread joint

Info

Publication number
JPH06221475A
JPH06221475A JP5031091A JP3109193A JPH06221475A JP H06221475 A JPH06221475 A JP H06221475A JP 5031091 A JP5031091 A JP 5031091A JP 3109193 A JP3109193 A JP 3109193A JP H06221475 A JPH06221475 A JP H06221475A
Authority
JP
Japan
Prior art keywords
torque
tightening
turn
joint
value
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
JP5031091A
Other languages
Japanese (ja)
Inventor
Takuya Atsumi
卓彌 厚見
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kawasaki Steel Corp filed Critical Kawasaki Steel Corp
Priority to JP5031091A priority Critical patent/JPH06221475A/en
Publication of JPH06221475A publication Critical patent/JPH06221475A/en
Withdrawn legal-status Critical Current

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  • Mutual Connection Of Rods And Tubes (AREA)
  • Non-Disconnectible Joints And Screw-Threaded Joints (AREA)

Abstract

PURPOSE:To obtain an efficient tightening method by calculating the remaining number of turns necessary to secure an objective delta toque value by use of the torque values at a first and a second bent points in an actual joint torque/turn value and torque values in a reference joint after the second bent point obtained in advance. CONSTITUTION:A first bent point from a first region into a second region and a second bent point from the second region into a third region are determined byfirst obtaining the tightening torque/turn values in a reference joint and then obtaining the tightening torque/turn values in tightening an actual joint successively and comparing them with the reference values. Accordingly, before entering the third region where the torque starts to increase rapidly with advance in the number of turns, the tightening toque quantity occurring in the first and second regions and the necessary delta torque quantity are obtained, so that the number of turns is calculated from a specified tightening torque/turn value in the third region. A final tightening torque value is thus set anew.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、石油・ガス等の採掘に
使用される油井管を管継手にて締結する場合の締め付け
方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastening method for fastening oil well pipes used for mining oil and gas with pipe joints.

【0002】[0002]

【従来の技術】油井の深さは数千mに及び、近年では1
万mにも達しようとしている。このような油井に竪て込
まれる油井管は膨大な数にのぼるが、これらは総て管継
手によって一連に接続される。係る管継手には、管及び
管継手自体の重量に起因する軸方向の引張力、周囲から
外周面に及ぼされる地圧力、内部流体による内周面への
押圧力等、各種の苛酷な力が作用する。
2. Description of the Related Art The depth of an oil well reaches several thousand meters, and in recent years,
It is about to reach 10,000 meters. Although the number of oil well pipes that are vertically inserted into such an oil well is enormous, they are all connected in series by pipe joints. Such pipe joints are subjected to various harsh forces such as an axial tensile force due to the weight of the pipe and the pipe joint itself, a ground pressure exerted from the periphery to the outer peripheral surface, and a pressing force exerted by the internal fluid on the inner peripheral surface. To work.

【0003】これらの力が油井深度の増大に従い、一層
苛酷なものとなることは言うまでもない。このような厳
しい条件下において使用し得る管継手にあっては、強大
な引張荷重に耐え得ると同時に確実なシール性を有する
ことが要求されている。
It goes without saying that these forces become more severe as the oil well depth increases. A pipe joint that can be used under such severe conditions is required to withstand a large tensile load and at the same time have a reliable sealing property.

【0004】油井管用継手として従来よりAPI(Amer
ican Petroleum Institute、アメリカ石油協会)規格の
ラウンドねじやバットレスねじなどのねじ継手が一般的
に使用されているが、上記要求に答えるためAPI規格
ねじよりも優れた特殊ねじ継手が使われる傾向にある。
As a joint for oil country tubular goods, API (Amer
ican Petroleum Institute (American Petroleum Institute) standard threaded joints such as round threads and buttress threads are generally used, but special threaded joints superior to API standard threads tend to be used to meet the above requirements. .

【0005】図2にAPI規格のラウンドねじ継手部
を、図3に典型的な特殊ねじ継手部を示す。API規格
ねじ継手の場合、シールはパイプ1の雄ねじ部3とカッ
プリング2の雌ねじ部の間で行なわれる。一方、特殊ね
じ継手では継手のねじなし部にシール部を設け、パイプ
先端部5とカップリング2のシール部7が金属接触する
ことでシール性を確保するようにしている。従って、特
殊ねじ継手の締め付け作業においては、パイプ先端部5
とカップリング2のシール部7が接触を開始した後、シ
ール性を確保するのに必要な面圧がこの接触部に生じる
まで締め付け作業を続けることが必要である。シール部
が接触を始めてから締め付けを終るまでのトルクをデル
タトルクと称する。面圧とデルタトルクは図4に示すよ
うに密接な関係にあり、シール性を確保するには適正な
デルタトルクを確保するまでパイプ1とカップリング2
を締め付けることが重要である。シール部が接触し始め
る前に発生するトルクをショルダートルクと称する。シ
ョルダートルクは、雄ねじと雌ねじの干渉の大小により
図5に示すように値は変動する。
FIG. 2 shows an API-standard round screw joint portion, and FIG. 3 shows a typical special screw joint portion. In the case of the API standard threaded joint, sealing is performed between the male threaded portion 3 of the pipe 1 and the female threaded portion of the coupling 2. On the other hand, in the special threaded joint, a seal portion is provided in the non-threaded portion of the joint, and the pipe tip portion 5 and the seal portion 7 of the coupling 2 are brought into metal contact with each other to ensure the sealing property. Therefore, when tightening the special threaded joint, the pipe tip 5
After the seal portion 7 of the coupling 2 starts contacting with each other, it is necessary to continue the tightening work until the surface pressure necessary to secure the sealing property is generated at this contact portion. The torque from the start of contact of the seal portion to the end of tightening is called delta torque. As shown in FIG. 4, the surface pressure and the delta torque are in a close relationship, and in order to secure the sealing property, the pipe 1 and the coupling 2 are required until a proper delta torque is secured.
It is important to tighten. The torque generated before the seal portions start contacting each other is called shoulder torque. The value of the shoulder torque fluctuates as shown in FIG. 5 depending on the magnitude of the interference between the male screw and the female screw.

【0006】特殊ねじ継手の締め付け作業としては、コ
ンパウンドと称するグリース、亜鉛、鉛等を主成分とす
る潤滑剤を雄ねじ部3、雌ねじ部4、パイプ先端部5、
トルクショルダー部6の全面或いは一部に塗布した後、
締め付け機にセットして所定のトルク値まで締め付ける
方式が一般的である。このような締め付け作業は、油田
において実施されるだけでなくパイプの製造工場におい
て管端にカップリングを取り付けて出荷する場合にも行
なわれる。
For the tightening work of the special screw joint, a grease called a compound, a lubricant containing zinc, lead or the like as a main component is used for the male screw portion 3, the female screw portion 4, the pipe tip portion 5,
After applying to all or part of the torque shoulder portion 6,
It is common to set it on a tightening machine and tighten it to a predetermined torque value. Such tightening work is performed not only in the oil field but also when the pipe manufacturing factory ships with the coupling attached to the pipe end.

【0007】特殊ねじ継手の締め付けトルク/ターン曲
線の一例を図6に示す。図のように前半は締め付けトル
クはパイプの回転(ターン)に従って徐々に増加する。
後半はターンの増加につれトルクは急激に増加し、適当
な締め付けトルク範囲を超えると継手自身が塑性変形し
てしまい使用できなくなる。従って、従来より特殊ねじ
継手の締め付けについてはシール性の点から所定のデル
タトルクの設定及び継手自身の塑性変形の点から締め付
けトルク範囲の設定がなされていた。締め付けトルク範
囲とは、公差内で雄ねじ或いは雌ねじ径が変化しショル
ダートルクが変動しても、所定のシール性を満足する必
要デルタトルク値が確保でき塑性変形の問題も起こらな
い範囲である。小径チュービングになるにつれ、ショル
ダートルクの値は相対的に大きくなり、同範囲は狭まる
傾向にある。
An example of the tightening torque / turn curve of the special threaded joint is shown in FIG. As shown in the figure, in the first half, the tightening torque gradually increases as the pipe turns.
In the latter half, the torque sharply increases as the number of turns increases, and beyond the proper tightening torque range, the joint itself plastically deforms and becomes unusable. Therefore, conventionally, when tightening a special screw joint, a predetermined delta torque is set from the viewpoint of sealing property and a tightening torque range is set from the viewpoint of plastic deformation of the joint itself. The tightening torque range is a range in which the necessary delta torque value satisfying the predetermined sealing property can be secured and the problem of plastic deformation does not occur even when the diameter of the male screw or the female screw changes within the tolerance and the shoulder torque changes. As the diameter of the tubing becomes smaller, the shoulder torque value becomes relatively larger and the range tends to become narrower.

【0008】[0008]

【発明が解決しようとする課題】然しながら、従来技術
には、以下の問題点がある。即ち、締め付け後半ではタ
ーンに対してトルクが急激に増加し、これが短時間で行
なわれるため、締め付け機の締め付け停止精度の点から
前記必要デルタトルクの確保及び最終目標トルク範囲で
の停止が難しい状況にあった。この対策の1つとして、
締め付け機の停止の応答性を考慮して停止指令から実際
に機械が停止するまでのトルク量(オーバーシュート
量)を考慮して早めに機械に停止指令を出すように設定
することが考えられているが、このオーバーシュート量
の見積りが大きすぎると必要デルタトルクの不足が生じ
ることになる。また、この見積りが小さすぎると最終目
標トルク範囲をオーバーしてしまい継手自身が塑性変形
してしまう場合があり、機械精度と応答性について問題
があった。他の対策として、締め付け速度を下げる方法
があるが生産性の点から新たな問題が起きると考えられ
る。
However, the prior art has the following problems. That is, in the latter half of tightening, the torque sharply increases with respect to the turn, and this is done in a short time, so it is difficult to secure the required delta torque and stop within the final target torque range from the viewpoint of tightening stop accuracy of the tightening machine. There was As one of the measures,
Considering the responsiveness of the tightening machine stop, it may be possible to set the machine to issue a stop command early considering the torque amount (overshoot amount) from the stop command until the machine actually stops. However, if the estimated overshoot amount is too large, the required delta torque will be insufficient. Further, if this estimate is too small, the final target torque range may be exceeded and the joint itself may be plastically deformed, and there was a problem in mechanical accuracy and responsiveness. As another measure, there is a method of reducing the tightening speed, but it is considered that a new problem will occur in terms of productivity.

【0009】本発明は、係る点から効率の良い油井管ね
じ継手の締め付け方法を提供するものである。
The present invention provides a method for tightening an oil country tubular goods threaded joint that is efficient in this respect.

【0010】本発明は、油井管を管継手にて締結する場
合、必要デルタトルクの不足が生ずることを防止し、か
つ最終目標トルク範囲をオーバーして継手自身が塑性変
形してしまうことを防止し、特殊ねじ継手に対して効率
の良い締め付け方法を提供することを目的とする。
The present invention prevents the necessary delta torque from becoming insufficient when the oil country tubular goods are fastened with a pipe joint, and prevents the joint itself from being plastically deformed beyond the final target torque range. However, it is an object of the present invention to provide an efficient tightening method for a special screw joint.

【0011】[0011]

【課題を解決するための手段】本発明者は、特殊ねじ継
手の締め付け方法について調査研究を重ねた結果、トル
ク/ターン曲線は4つの領域に区分でき、それぞれの領
域に関して[締め付けトルク/ターン]の値(トルク増
加率)がねじ或いはシール部の干渉と密接な関係がある
ことを見いだし、更に研究を重ねたところ、特殊ねじ継
手の締め付け方法において、(1) 雄ねじと雌ねじの干渉
によりトルクが発生する第1の[締め付けトルク/ター
ン]曲線領域と、パイプ先端のシール部がカップリング
のシール部に接触することによりトルクが発生する第2
の[締め付けトルク/ターン]曲線領域と、トルクショ
ルダー部が接触することによりトルクが発生する第3の
[締め付けトルク/ターン]曲線領域と、過剰締め付け
により継手自身が塑性変形する第4の[締め付けトルク
/ターン]曲線領域とを有する基準継手について、予
め、第3の[締め付けトルク/ターン]曲線の値を求め
ておき、(2) 実際の継手の締め付け時に、[締め付けト
ルク/ターン]曲線を求め、第1の[締め付けトルク/
ターン]曲線領域から第2の[締め付けトルク/ター
ン]曲線領域に移行する第1屈折点を経過し、更に第2
の[締め付けトルク/ターン]曲線領域から第3の[締
め付けトルク/ターン]曲線領域に移行する第2屈折点
を経過したことを認めるとともに、第1屈折点と第2屈
折点の各点でのトルク値を求めた後、(3) 上記実際の継
手の最終締め付け段階で目標デルタトルク値を確保する
に必要な残りのターン数を、上記第1屈折点と第2屈折
点の各点でのトルク値と、前記第3の[締め付けトルク
/ターン]曲線の値とを用いて計算し、(4) 当該実際の
継手をこの計算ターン数で締め付け終了することにより
効率的に油井管ねじ継手を締め付けることに成功した。
As a result of repeated research and studies on the tightening method of special threaded joints, the present inventor can divide the torque / turn curve into four regions, and [tightening torque / turn] for each region. It was found that the value of (the torque increase rate) is closely related to the interference of the screw or the seal part, and further research has shown that in the tightening method of the special screw joint, (1) the torque is increased due to the interference between the male screw and the female screw. The first [tightening torque / turn] curve region that occurs and the second torque that occurs when the seal portion of the pipe tip contacts the seal portion of the coupling
[Tightening torque / turn] curve area, the third [Tightening torque / turn] curve area in which torque is generated by the contact of the torque shoulder, and the fourth [Tightening torque / turn] curve in which the joint itself is plastically deformed by excessive tightening. The value of the third [tightening torque / turn] curve is obtained in advance for the reference joint having the torque / turn curve region, and (2) the [tightening torque / turn] curve is set when the actual joint is tightened. Find the first [tightening torque /
The first turn point that transitions from the [turn] curve area to the second [tightening torque / turn] curve area is passed, and then the second
It is acknowledged that the second inflection point transitioning from the [Tightening torque / turn] curve area of to the third [Tightening torque / turn] curve area has passed, and at each point of the first and second inflection points. After obtaining the torque value, (3) determine the remaining number of turns necessary to secure the target delta torque value at the final tightening stage of the actual joint at each of the first and second inflection points. The torque value and the value of the third [tightening torque / turn] curve are used for calculation, and (4) the actual well joint is tightened at this calculated number of turns to efficiently form an oil well pipe threaded joint. Successfully tightened.

【0012】[0012]

【作用】本発明者は、特殊ねじ継手の締め付け時のトル
ク/ターン曲線について詳細に調査したところ、[締め
付けトルク/ターン]の値がねじ或いはシール部の干渉
と密接な関係があることを確認できた。トルク/ターン
曲線は図7に示すように[締め付けトルク/ターン]の
値即ち同曲線の傾きにより4つの領域に分類できること
が明らかとなった。
The present inventor conducted a detailed investigation on the torque / turn curve during tightening of the special threaded joint, and confirmed that the value of [tightening torque / turn] was closely related to the interference of the screw or the seal part. did it. It was revealed that the torque / turn curve can be classified into four regions by the value of [tightening torque / turn], that is, the slope of the curve, as shown in FIG.

【0013】第1の領域は、雌ねじと雄ねじの干渉によ
りトルクが発生する部分であり曲線の傾きはねじ同士の
干渉或いは摩擦の状態に影響され、第2の領域は、ピン
先端のシール部がカップリングのシール部に接触するこ
とによりトルクが発生する部分であり同傾きはシール部
の干渉或いは摩擦の状態に影響されることがわかった。
第3の領域は、トルクショルダー部が接触することによ
りターンの増加に対してトルクが急激に増加する部分で
ある。第3の領域の傾き[締め付けトルク/ターン]
は、第1、第2の領域に比較して同デザイン、同サイズ
及び同グレードの継手であればほとんど変動しないこと
がわかった。第4の領域は、過剰締め付けにより継手自
身が塑性変形する部分であり、この範囲に至るまでに締
め付けを終了させる必要がある。
The first region is a portion where torque is generated by the interference between the female screw and the male screw, and the inclination of the curve is affected by the interference or friction of the screws. In the second region, the seal portion at the tip of the pin is used. It was found that the torque is generated by contact with the seal portion of the coupling, and the inclination is affected by the interference or frictional state of the seal portion.
The third region is a portion where the torque rapidly increases as the number of turns increases due to the contact of the torque shoulder portion. Inclination of the third area [tightening torque / turn]
It has been found that, as compared with the first and second regions, the joint has almost the same design, size and grade. The fourth region is a portion where the joint itself plastically deforms due to excessive tightening, and it is necessary to finish tightening before reaching this range.

【0014】尚、特殊ねじ継手に関して同一コンパウン
ドの条件下で数多くの締め付けを行ない[締め付けトル
ク/ターン]の値に注目して検討したところ以下の3つ
のことも明らかとなった。
When the special threaded joint was tightened a number of times under the same compound condition and the value of [tightening torque / turn] was taken into consideration, the following three things were also clarified.

【0015】1)上記第1、第2の領域において[締め付
けトルク/ターン]の値は、ねじ或いはシールの干渉、
ねじ面或いはシール面の被膜処理条件、仕上げ加工面粗
さ、締め付け作業時の温度等の環境条件などにより変化
するもののその変動量は小さい。
1) In the first and second regions, the value of [tightening torque / turn] is the interference of screws or seals,
Although it varies depending on the coating conditions of the screw surface or the sealing surface, the finished surface roughness, the environmental conditions such as the temperature during tightening work, etc., the fluctuation amount is small.

【0016】2)上記第3の領域では、ねじ先端或いはト
ルクショルダー部の加工[締め付けトルク/ターン]の
値は一定値である。
2) In the third region, the value of the machining [tightening torque / turn] of the screw tip or the torque shoulder portion is a constant value.

【0017】3)第1の領域→第2の領域→第3の領域に
つれて[締め付けトルク/ターン]の値は増加する。
3) The value of [tightening torque / turn] increases as the first area → the second area → the third area.

【0018】以上の検討結果を用いて、予め基準継手の
[締め付けトルク/ターン]の値を求めておき、実際の
継手の締め付け時の[締め付けトルク/ターン]の値を
順次求めて比較することにより、第1の領域から第2の
領域への遷移点(第1屈折点)、第2の領域から第3の
領域への遷移点(第2屈折点)を確定できることがわか
った。これよりターン数の増加量に対して急激にトルク
が増加する第3の領域へ締め込まれる前に、第1と第2
の領域で生成される締め付けトルク量及び必要デルタト
ルク量を求めることができることから、第3の領域の範
囲で特定されている[締め付けトルク/ターン]の値か
ら締め込む量(ターン数)を算出でき、最終締め付けト
ルク値を再設定できることがわかった。
Using the results of the above examination, the [tightening torque / turn] value of the reference joint is obtained in advance, and the [tightening torque / turn] value during actual fastening of the joint is sequentially obtained and compared. Thus, it was found that the transition point from the first region to the second region (first refraction point) and the transition point from the second region to the third region (second refraction point) can be determined. From this, before being tightened into the third region where the torque sharply increases with the increase in the number of turns, the first and the second
Since the tightening torque amount and the required delta torque amount generated in the area of can be obtained, the tightening amount (number of turns) is calculated from the value of [tightening torque / turn] specified in the range of the third area. It was found that the final tightening torque value can be reset.

【0019】本発明の方法を適用したAPIグレードL
80、外径88.9mmサイズ、肉厚6.45mmの特殊ねじ継手の締
め付け結果の一例を図1に示す。本発明方法を使用する
ことにより、従来と比較してその不良率を従来の30%以
下に低減することが可能となった。
API grade L to which the method of the present invention has been applied
Fig. 1 shows an example of the tightening results for a special threaded joint with a diameter of 80, an outer diameter of 88.9 mm, and a wall thickness of 6.45 mm. By using the method of the present invention, it has become possible to reduce the defective rate to 30% or less of the conventional one as compared with the conventional one.

【0020】[0020]

【実施例】APIグレードL80、外径88.9mm、肉厚6.45
mmの特殊ねじ継手を用いて、ガスシール性を保つために
適正なデルタトルクの確保及び継手自身が変形していな
いかを調査する目的で締め付け実験及び同継手について
ガスリーク試験を実施した。前述の基準継手に関して上
記第1の領域〜第3の領域の傾きと実験結果を表1に示
す。表1において、本発明方法に基づいて、第1、第2
の領域での[締め付けトルク/ターン]の値及び基準継
手の同値と比較しながら残りの必要デルタトルクを順次
求めてデルタトルク値と最終締め付けトルク値を適当な
範囲に規制した本発明例No.1〜10はいずれもリークの発
生がなかった。これに対して、比較例No.11 〜20は、本
発明方法を用いなかったためにリークを発生している場
合がある。No.l2 は締め付け機の停止精度の点からオー
バーシュート量の見積りが大きすぎたためにデルタトル
ク不足となりガスリーク試験でリークが確認されてい
る。また、No.19 は同締め付け機の停止が遅れたため継
手自身が塑性変形を起こしたため、ガスリーク試験でリ
ークが発生している。
[Example] API grade L80, outer diameter 88.9 mm, wall thickness 6.45
Using special mm mm threaded joints, a tightening experiment and a gas leak test were carried out for the purpose of securing an appropriate delta torque to maintain the gas sealability and investigating whether the joint itself was deformed. Table 1 shows the inclinations of the first to third regions and the experimental results regarding the above-mentioned reference joint. In Table 1, based on the method of the present invention, first, second
In the present invention example No. in which the delta torque value and the final tightening torque value are regulated in an appropriate range by sequentially obtaining the remaining necessary delta torque while comparing the value of [tightening torque / turn] in the area of and the same value of the reference joint. No leak occurred in any of 1 to 10. On the other hand, Comparative Examples Nos. 11 to 20 may cause a leak because the method of the present invention was not used. In No.l2, the overshoot amount was estimated too much from the standpoint of the stopping accuracy of the tightening machine, so the delta torque became insufficient and a leak was confirmed in the gas leak test. In No. 19, the joint itself was plastically deformed due to a delay in stopping the tightening machine, and a leak occurred in the gas leak test.

【0021】[0021]

【表1】 [Table 1]

【0022】即ち、本発明に基づいて、(1) 雄ねじと雌
ねじの干渉によりトルクが発生する第1の[締め付けト
ルク/ターン]曲線領域と、パイプ先端のシール部がカ
ップリングのシール部に接触することによりトルクが発
生する第2の[締め付けトルク/ターン]曲線領域と、
トルクショルダー部が接触することによりトルクが発生
する第3の[締め付けトルク/ターン]曲線領域と、過
剰締め付けにより継手自身が塑性変形する第4の[締め
付けトルク/ターン]曲線領域とを有する基準継手につ
いて、予め、第3の[締め付けトルク/ターン]曲線の
値を求めておき、(2) 実際の継手の締め付け時に、[締
め付けトルク/ターン]曲線を求め、第1の[締め付け
トルク/ターン]曲線領域から第2の[締め付けトルク
/ターン]曲線領域に移行する第1屈折点を経過し、更
に第2の[締め付けトルク/ターン]曲線領域から第3
の[締め付けトルク/ターン]曲線領域に移行する第2
屈折点を経過したことを認めるとともに、第1屈折点と
第2屈折点の各点でのトルク値を求めた後、(3) 上記実
際の継手の最終締め付け段階で目標デルタトルク値を確
保するに必要な残りのターン数を、上記第1屈折点と第
2屈折点の各点でのトルク値と、前記第3の[締め付け
トルク/ターン]曲線の値とを用いて計算し、(4) 当該
実際の継手をこの計算ターン数で締め付け終了すること
により効率的に締め付け作業が実施できる。
That is, according to the present invention, (1) the first [tightening torque / turn] curve region where torque is generated by the interference between the male screw and the female screw, and the seal portion at the tip of the pipe contact the seal portion of the coupling. A second [tightening torque / turn] curve area in which torque is generated by
Reference joint having a third [tightening torque / turn] curve area in which torque is generated by contact of the torque shoulder portion and a fourth [tightening torque / turn] curve area in which the joint itself plastically deforms due to overtightening About the 3rd [tightening torque / turn] curve, (2) [tightening torque / turn] curve at the time of actual tightening of the joint, and the 1st [tightening torque / turn] curve The first bending point passing from the curved region to the second [tightening torque / turn] curved region is passed, and further from the second [tightening torque / turn] curved region to the third
[Tightening torque / turn] curve area
After confirming that the inflection point has passed and obtaining the torque value at each of the first and second inflection points, (3) secure the target delta torque value at the final tightening stage of the actual joint. The remaining number of turns required for is calculated using the torque value at each point of the first and second inflection points and the value of the third [tightening torque / turn] curve, and (4 ) The tightening work can be performed efficiently by finishing the tightening of the actual joint with the calculated number of turns.

【0023】尚、上記(3) でターン数を計算するに先立
ち、実際の継手について、トルク/ターン曲線における
第2屈折点以降の[締め付けトルク/ターン]の値が
(1) で基準継手について予め求めた値と一致することを
確認するものであっても良い。
Before calculating the number of turns in the above (3), the value of [tightening torque / turn] after the second inflection point in the torque / turn curve of the actual joint is
It may be possible to confirm that it agrees with the value obtained in advance for the reference joint in (1).

【0024】[0024]

【発明の効果】以上のように本発明によれば、油井管を
管継手にて締結する場合、必要デルタトルクの不足が生
ずることを防止し、かつ最終目標トルク範囲をオーバー
して継手自身が塑性変形してしまうことを防止し、特殊
ねじ継手に対して効率の良い締め付け方法を得ることが
できる。
As described above, according to the present invention, when the oil country tubular goods are fastened by the pipe joint, the necessary delta torque is prevented from becoming insufficient, and the final target torque range is exceeded so that the joint itself is It is possible to prevent plastic deformation and obtain an efficient tightening method for a special screw joint.

【図面の簡単な説明】[Brief description of drawings]

【図1】図1は本発明方法に関わる締め付け方法を用い
た場合の締め付け不良率を従来方法と比較して示す図で
ある。
FIG. 1 is a diagram showing a tightening failure rate when a tightening method according to the method of the present invention is used, in comparison with a conventional method.

【図2】図2は従来の技術に関わるAPI規格のねじ継
手部を示す断面図である。
FIG. 2 is a cross-sectional view showing a threaded joint portion of API standard relating to a conventional technique.

【図3】図3は本発明に関わる特殊ねじ継手部を示す断
面図である。
FIG. 3 is a cross-sectional view showing a special screw joint portion according to the present invention.

【図4】図4はデルタトルクとシール部面圧の関係を示
す線図である。
FIG. 4 is a diagram showing a relationship between delta torque and seal portion surface pressure.

【図5】図5はねじ干渉量とショルダートルクの関係を
示す線図である。
FIG. 5 is a diagram showing a relationship between a screw interference amount and a shoulder torque.

【図6】図6は締め付け時のターン(回転)と締め付け
トルクの関係を示す線図である。
FIG. 6 is a diagram showing a relationship between a turn (rotation) and tightening torque during tightening.

【図7】図7は締め付け時のターン(回転)と締め付け
トルクの関係を示す線図である。
FIG. 7 is a diagram showing a relationship between a turn (rotation) and tightening torque during tightening.

【符号の説明】[Explanation of symbols]

1 パイプ 2 カップリング 3 雄ねじ部 4 雌ねじ部 5 パイプ先端部 6 トルクショルダー部 7 シール部 1 Pipe 2 Coupling 3 Male Threaded Part 4 Female Threaded Part 5 Pipe Tip Part 6 Torque Shoulder Part 7 Sealed Part

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 油井管ねじ継手の締め付け方法におい
て、 雄ねじと雌ねじの干渉によりトルクが発生する第1の
[締め付けトルク/ターン]曲線領域と、パイプ先端の
シール部がカップリングのシール部に接触することによ
りトルクが発生する第2の[締め付けトルク/ターン]
曲線領域と、トルクショルダー部が接触することにより
トルクが発生する第3の[締め付けトルク/ターン]曲
線領域と、過剰締め付けにより継手自身が塑性変形する
第4の[締め付けトルク/ターン]曲線領域とを有する
基準継手について、予め、第3の[締め付けトルク/タ
ーン]曲線の値を求めておき、 実際の継手の締め付け時に、[締め付けトルク/ター
ン]曲線を求め、第1の[締め付けトルク/ターン]曲
線領域から第2の[締め付けトルク/ターン]曲線領域
に移行する第1屈折点を経過し、更に第2の[締め付け
トルク/ターン]曲線領域から第3の[締め付けトルク
/ターン]曲線領域に移行する第2屈折点を経過したこ
とを認めるとともに、第1屈折点と第2屈折点の各点で
のトルク値を求めた後、 上記実際の継手の最終締め付け段階で目標デルタトルク
値を確保するに必要な残りのターン数を、上記第1屈折
点と第2屈折点の各点でのトルク値と、前記第3の[締
め付けトルク/ターン]曲線の値とを用いて計算し、 当該実際の継手をこの計算ターン数で締め付け終了する
ことを特徴とする油井管ねじ継手の締め付け方法。
1. A method for tightening an oil well pipe threaded joint, wherein the first [tightening torque / turn] curve region where torque is generated by the interference between the male screw and the female screw, and the seal portion of the pipe tip contacts the seal portion of the coupling. The second [tightening torque / turn] in which torque is generated by
A curved region, a third [tightening torque / turn] curved region in which torque is generated by the contact of the torque shoulder portion, and a fourth [tightening torque / turn] curved region in which the joint itself plastically deforms due to excessive tightening. The value of the third [tightening torque / turn] curve is obtained in advance for the reference joint having the above. When the actual joint is tightened, the [tightening torque / turn] curve is obtained, and the first [tightening torque / turn] curve is obtained. ] A first inflection point passing from the curved region to the second [tightening torque / turn] curved region has passed, and further, from the second [tightening torque / turn] curved region to the third [tightening torque / turn] curved region After confirming that the second inflection point transitioning to No. 1 has passed, and obtaining the torque value at each point of the first inflection point and the second inflection point, The remaining number of turns required to secure the target delta torque value at the final tightening stage is determined by the torque value at each of the first and second inflection points and the third [tightening torque / turn] curve. And the value of, and tightening of the actual joint is completed with this calculated number of turns.
JP5031091A 1993-01-28 1993-01-28 Tightening method for oil well pipe thread joint Withdrawn JPH06221475A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5031091A JPH06221475A (en) 1993-01-28 1993-01-28 Tightening method for oil well pipe thread joint

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5031091A JPH06221475A (en) 1993-01-28 1993-01-28 Tightening method for oil well pipe thread joint

Publications (1)

Publication Number Publication Date
JPH06221475A true JPH06221475A (en) 1994-08-09

Family

ID=12321737

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5031091A Withdrawn JPH06221475A (en) 1993-01-28 1993-01-28 Tightening method for oil well pipe thread joint

Country Status (1)

Country Link
JP (1) JPH06221475A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001086185A1 (en) * 2000-05-10 2001-11-15 Sumitomo Metal Industries, Ltd. Method of tightening pipe joint
WO2014096663A1 (en) 2012-12-18 2014-06-26 Vallourec Oil And Gas France Method for checking a screwing state of a tubular threaded seal
FR3057664A1 (en) * 2016-10-19 2018-04-20 Vallourec Oil & Gas France DEVICE FOR DETERMINING THE ASSEMBLY QUALITY OF THREADED TUBULAR COMPONENTS
US20240301756A1 (en) * 2023-03-10 2024-09-12 Baker Hughes Oilfield Operations Llc Control of tubular connections based on estimation of turns remaining

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001086185A1 (en) * 2000-05-10 2001-11-15 Sumitomo Metal Industries, Ltd. Method of tightening pipe joint
WO2014096663A1 (en) 2012-12-18 2014-06-26 Vallourec Oil And Gas France Method for checking a screwing state of a tubular threaded seal
US10309168B2 (en) 2012-12-18 2019-06-04 Vallourec Oil And Gas France Method for checking a screwing state of a tubular threaded seal
FR3057664A1 (en) * 2016-10-19 2018-04-20 Vallourec Oil & Gas France DEVICE FOR DETERMINING THE ASSEMBLY QUALITY OF THREADED TUBULAR COMPONENTS
WO2018073197A1 (en) 2016-10-19 2018-04-26 Vallourec Oil And Gas France Device for determining the assembly quality of a tubular threaded joint
US10760360B2 (en) 2016-10-19 2020-09-01 Vallourec Oil And Gas France Device for determining the connection quality of a threaded tubular connection
US20240301756A1 (en) * 2023-03-10 2024-09-12 Baker Hughes Oilfield Operations Llc Control of tubular connections based on estimation of turns remaining

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Effective date: 20000404