SA01220173B1 - screw-threaded pipe joint - Google Patents

Abstract

Abstract: The present invention relates to a screw-threaded pipe joint having a male portion (10) and a female portion (12), having screw threads (11, 13). The male thread (11) extends to a position adjacent to a stop shoulder (18) on the female portion (12) which has a bore having a conical cross-section with a rounded top. The bore is prepared to receive a head part having a conical cross-section and a rounded apex, and the radius of curvature is greater than the radius of the apex of the bore, which provides a lock with improved stress distribution properties when a torque is applied. It is possible that the surface wall of the applied cone facing outward (33) on the male portion (10) includes an angle between 28 and 36 degrees with the longitudinal axis of the pipe. The angle of the opposite conical wall on the female portion may be between 28 and 38 degrees on the same axis. It is possible that the male portion (10) includes a second surface with a stress distribution (41) having a concave curve.

Description

Y _ — Screw-threaded pipe joint Full description

background of the invention

The present invention relates to a connection for joining pipes together, especially pipes

intended for underground use in the gas and oil industry, for example.

when transporting a fluid; such as oil or natural gas; between two sites; pipe lines o are used; when possible; Since those are the most cost effective ways. And done

These pipelines are generally constructed by linking individual pipes together. It represents locations

The pipes are connected to the cut-off points of the inner and outer surface of the pipelines; And therefore considered

Sources of weakness in the downstream pipeline.

It is also important that any weaknesses be reduced as far as possible; Since no loss

0 for fluids from pipes is a waste of resources and a disaster for Al at the same time. Furthermore; Wasted fluid may increase the risk to individuals due to fires and explosions. Also, replacing insufficient or leaking links is not always easy. Especially in the oil or gas industry, pipelines are in relatively inaccessible locations and replacement is often difficult and expensive.

Screw-threaded A number of workarounds have been used to bypass the vulnerabilities. The threaded connection 1 is considered the joint together to prevent the separation of individual pipes, threads, and the teeth of cle gud work in most solutions, joint 0, whether at the axis or radius, and the connections must be designed in the first place so as not to allow any fluids inside them to leak. lag, it must be able to withstand large differences in pressure within the width of the radius

vv, since the pressure difference is usually a positive component in an outward direction of the radius. Also, threaded connections require the engagement of two threaded parts, one of which is on each tube, and then they are joined together. Interlocking is usually done by applying a torque. The two threaded parts are usually made so that the teeth are complementary to each other.

‎YVR

Y —_ _ given in GB 1 587 836 (VALLOUREC) A pipe fitting having a sealing shoulder on one pipe working in combination with a Jee stop shoulder on the other pipe to form a stop lock .pipe to form a seal There are a number of problems with this lock. Firstly, the metal of which this lock is made is affected by the intense torque exerted when the pipes are screwed together. If the necessary care is not taken, the link will slip or dent. Secondly, the connections formed may form a point of interruption in the path connecting the parts of the pipe and the other part. The present invention aims to introduce a threaded connection that solves the above-mentioned problems. General description of the invention 0 according to the present invention; A screw threaded joint was provided for Cua pipes. The length of the first pipe at one end is a male screw portion 10:; The length of the second tube at one end shall be a female portion with complementary screw thread ¢ and the two portions shall be designed to engage with a gut along the greater part of the axial length of the threaded portions; The threaded teeth 1 _ shall be inclined in the same direction and at an angle sala to the longitudinal axis of the length of the tube; and the male portion extends to a position adjacent to one of the stop shoulders complementing the AY) so that each stop shoulder complementing includes a recess in the form of a cone having a round Aad; The recess for receiving the head is in the form of a cone having a rounded apex of a radius marginally larger than the radius of the recess; What results in the surface of the jig cracks is that it has strong properties in the stress distribution when a Y-torque is applied to the joint. preferably to have the wall of the cone on the outside of the threaded male part being used; An angle between 78 and “degrees” with the longitudinal axis of the pipe. It is particularly desirable for the wall of the cone to have an angle of YY Ye degrees with the longitudinal axis of the pipe; It is more preferable for the angle to be We degrees. vo and it is preferable that the opposite conical wall on the female threaded part have an ankle between YA and 8” degrees with the longitudinal axis of the threaded male part.

— $ _ <male threaded portion It is preferable that the angle of the cone wall of the female threaded part be greater than the angle of the cone wall of the -male threaded portion and it is preferred that the male portion includes a distributed surface stress so that the stop shoulder contacts the first tooth of the pivot pin. The stress distributed surface is preferably in the form of -concave curve ia dade and the radius of curvature of the concave curve of the stress distributed surface is preferably between 0.0078 . Ao cm and it is most preferred to be 0.1 AY cm . It is preferable that the male portion of the threaded WS includes both ends at an angle ranging from VE YE degrees with the surface perpendicular to the longitudinal axis of the pipe. Preferably, the angle is 0 between VA and 17 degrees. It is particularly desirable that the angle be yo degrees. The angle of the end shoulder of the threaded female part is preferably between YE VY degrees; With the surface perpendicular to the longitudinal axis of the threaded male part. It is a good idea for this angle to be between YA VE degrees. It is preferable that the end shoulder angle of the threaded female part be less than the angle of the end shoulder of the threaded female part. \o When the joint is axially compressed ¢ the threaded male portion tends to bend inward due to the inward axial forces generated by the compression. The resulting deformation is often known as -barrel deformation. It is preferable that the inner surface used for the stop shoulder be concave to reduce the effects of the barrel deformation. It is preferable that the radius of the concave surface be 0 #sneeze between 4, 4 can 0,Y and most preferably 8.1 cm. BRIEF EXPLANATION OF THE DRAWINGS The invention will now be described in more detail by reference to the accompanying drawings illustrating; By means of examples of only two models of a pipe threaded connection. The drawings include the following: Figure 1 is an axial cross-sectional view of the screw connection between a bolt and a box.

—- M __ shape? A larger cross-sectional axial view of the stopping shoulder of the screw in Fig. 1. Fig. ? It is an axial sectional view of the second z-model from shoulder 1 of the screw stop. Figure ¢ is an axial sectional view of the bolt and box connection. Description all for my detail 1: m Referring initially to Fig. 1; bolt 01 with threads 11 engages in box 11 with corresponding threads VY and bolt 01 engages in box VY connection. Pin 0 and box VY are tapered towards respective ends VE and 91 so that the total width of the tube wall in region 11 remains largely constant. The stop shoulder 17 of pin 0 engages with the corresponding stop shoulder VA on box 11 to form a lock. 0 and when using; The threaded parts 11 and 71 are engaged by applying a torque to the two tubes until a lock is formed by contact between surfaces 19 surfaces, 10 and 17 of the VY stop shoulder with surfaces YY surfaces and 77 YE surfaces, respectively, with a shoulder The stop AA has then been shown in more detail in the figure Y and the stop shoulder of the screw yo has a stop shoulder 01 at one end in the shape of a frustum cone .71 and the stop shoulder YY has a number of 1 The VE YY surfaces, YY surfaces engage with the corresponding stop shoulder in the box. and between the vy surface and the stop shoulder ;”,; The shoulder of the Gili) is curved with a radius of curvature of 0.077 cm. Surface YY includes an angle of 00 degrees with the longitudinal axis of the pin. The YE stop shoulder includes an angle of yo degrees with the surface perpendicular to the longitudinal axis of the Noa screw and the sealing shoulder has a head part with a conical cross-section with a 700. curved apex; The conical part is bounded by side walls NES YY and the surface TY connecting the wall of Yo threads 77 to the surface YY is curved. The surface YY has a radius of curvature pa by AY Another embodiment of the screw described above is shown in Fig. 7. In this embodiment; Nail 0 includes another curved surface cf) which has a radius of curvature A of 20.6 cm. And the bending is determined vo: so that when a torque is applied to the nail 40 while it is attached to the box; Stress is caused by:

+ - the torque in the release of an internal diagonal force that causes the screw 56 to bend so that the surface 1 ; fuses with the box. In this way; There shall be no protrusions or interruptions in the path of fluid flow through the pipe. This discontinuity, which often results in a spiral movement of the fluid flow, requires more energy, 0, to move the fluid along the pipe. Furthermore; The break points are usually more vulnerable than other parts of the surface to the chemical or physical impulse from the transported fluid; What leads to the weakness of these parts and their erosion due to the fluid, and the figure shows; Another manifestation of the screw-and-box connection according to the present invention. The surface of 0) of screw 04 has a radius of curvature of 0.077 cm. This radius of curvature is 0 greater than that of the corresponding curved surface 57 on the box oF which has a radius of curvature of 0.070 cm and during the bonding process (Say) taking advantage of the gap 54 resulting from the difference in curvature. Since the two surfaces (0 5 oY) do not touch each other until the pin and box engage properly. The stress in these areas is reduced to a minimum. Once pin 50 and box OFF are properly engaged; With the application of a greater torque, the material - from which the tube is made - begins to be subjected to viscous flow as a result of the high stress to which it is subjected. It is also possible to take advantage of the © gap by allowing matter to experience the flow of these forces within it. Apart from this improvement by locking; The flow of material into the empty space does not create any additional stress within the box or pin. This is the case if the shoulder of the screw is unable to flow freely. Another advantage of the curvature difference is that it allows for greater smoothness and internal movement of the lock© region of the linkage which also reduces unnecessary stress. The above manifestations may be individual or combined; This is to reduce the areas of high stress that are normally found inside the stop shoulder when the tube on which the shoulder is placed is connected to a second tube. These features allow energy to be transferred to the stop shoulder when torque is applied so that it is distributed over a larger area along the stop shoulder area and within the threaded area. Yo Although there is a desire not to be limited to a specific theory, it is known that the combination of the aspects discussed here works to redistribute the stress forces resulting from applying a torque to the joint.

Dr -

Approximately 795-4850 stresses are concentrated in the J region of the connecting pipe pair. And cause energy

stored in this area to reduce the viscous performance of the material from which the pipes are made.

Furthermore, due to the equal control of interference throughout the threaded portion; Especially on the root

The bolt, the peak of the coupling and the sides of the load and with the presence of the Aland lock geometry, the coupling is able to receive ade higher, which leads to an improvement in the performance of the coupling in terms of pressure.

Although the shape; Shows that the two walls of screw 075 00 are parallel to the walls of box oY and 8

and they have the same angle; This is unlikely. In many embodiments of the present invention it is

The advantage is to use another angle. For example, in a preferred form (not shown in the figure); He is

Surface of female portion p081?_threaded corresponding to surface YY in Figure 1 where angle YY is 0 degrees; Whereas, the surface opposite the shoulder YE is at an angle of VA degrees.

In general, the surface YY may include an angle ranging from YU to YA degrees having a longitudinal axis from

the longitudinal axis of the tube; while the opposite surface on the female portion has a threaded

Angles between 78 and 8" degrees.

oil The end shoulder YE may be at an angle between VE and 74° with the perpendicular surface 1 to the longitudinal axis of the pipe; while the opposite shoulder on the female part has the female portion

The coil is an angle between 11 and 74 degrees.

The angle difference reduces flexural stress in the locking region when a torque is applied; And it is allowed

Using torque energy in a more efficient way.

The sealing shoulders presented here can be utilized in the manufacture of pipes from many standard materials © used in this industry.

The typical material for manufacturing pipes is steel. The grade of steel used can be chosen

Pipe is one of the grades commonly used in the pipeline industry. and for example; the

The following types are considered suitable for use according to this invention - according to the standard designation - and they are:

5, 155, 1180, 1.80 C905, 95©, 2110, and 0125. The surfaces of the tubes may also be subjected to antifriction treatment prior to use.

The total width of the pipe varies between WA cm and not .71 cm in overall diameter. And the most typical that

It ranges between 6 and * 11 cm.

A — — It is known here, of course, that the invention is not limited to the particulars contained therein which are put forward for example; However, many modifications and alterations can be made within the scope of this invention.

Claims (1)

f) Pipes protection elements for pipes, screw-threaded joint Jab, the invention relates to 1-1 male, where the length of the first pipe at one end is a threaded male part Y, and the length of the second pipe at one end is a screw threaded portion oY complementary screw works as a complementary part female portion ¢ and the two parts are designed to interlock together with the length of the largest part of ¢ thread 0 in the same Ale and the threaded teeth Adsl the axial length of the parts 1 heading at an acute angle towards the central longitudinal axis of the joint; The male portion 7 which includes at least the stop-shoulder extends the male portion A the head next to a dams shoulder complementary on the female portion; The advantage here is that the shoulder 9 has a conical receiver with a JeSdl stop-shoulder 01 cross-section in the form of an ellipse and a round receiver top; The conical receiver part 1 is tuned to receive the cone-shaped head part 1 receiver part Ad and a rounded top of radius greater than the cone VY radius n; And therefore. A locking surface is provided when torque is applied to the joint; the inner surface used for the sealing shoulder is concave as seen from the inside of the pipe. —Y 1 screw-threaded joint Adele of claim 1 wherein The used conical Y wall facing outward from the head part at an angle between YA 7 and 7 degrees with the longitudinal axis of the joint —V 1 screw-threaded joint according to the element of protection oY Whereas, the conical Y wall has an angle between YO and 7° with the longitudinal axis of the joint .longitudinal axis of the joint 1 - 11. Yes -; 1 screw-threaded joint according to Clause 1, where the conical wall used and facing inwards on the conical receiving part has an angle of 7 ranging between YA and 8” degrees with the longitudinal axis of the joint .the joint ¢ 1 m- | A screw-threaded joint according to claim 0 wherein the angle of the employed inward-facing conical wall on the receiving conical portion has ¥ greater than the angle of the employed outward-facing conical wall of the ¢ head portion. 1 — 1 screw-threaded joint In accordance with protection Cus 0, the threaded male portion Y includes a second surface for stress distribution connecting the stop-shoulder to the threaded portion of the pipe . -1 1 - screw-threaded joint according to the Leal element) since it is in the Y cross section; The second stress-distributing surface takes a concave curve W sha ¥ intersects with the -stop-shoulder Any - -+ 1 screw-threaded joint according to the element of protection ¥ where half Y is the radius of curvature of the concave curve For the second distributed surface, the stress ranges between ve Ao 3 Y cm. 9 — 1 screw-threaded joint according to the element of protection A, whereby the radius of curvature of the concave curve of the second stress distributing surface starts from 0.041 cm. V+ 1 screw-threaded joint according to protection element 1 where the male portion threaded includes WS at the end at an angle ranging between VE VE degrees with the longitudinal axis of the pipe. 11 1 screw-threaded joint in accordance with claim 10; Cun that the Y angle of the stop-shoulder is between VA and 10° with the perpendicular surface 1 on the longitudinal axis of the pipe. Alay -1" 1 screw-threaded according to claim 11 where the female part al glad female portion Y includes a terminal shoulder at an angle between 11 and 74 degrees dull 1 of the surface_perpendicular to the longitudinal_axis For the -male threaded portion ¢ ——VV 1 screw-threaded joint according to Clause 107, whereby the terminal shoulder 1 of the threaded female part has an angle ranging between VE and 18 degrees, dually 7 to the surface perpendicular to the longitudinal axis of the threaded male part. threaded portion ¢ 11216. 1 4 threaded joint according to the element of protection VY, where the angle of the end shoulder of the female threaded part is less than the angle of the end shoulder of the 7-male threaded portion —Vo 1 screw-threaded joint pursuant to Clause 101 wherein the Y surface used for the sealing shoulder of the male portion 3 is concave as seen from the inside of the tube. 1 7 screw-threaded joint According to Claim 10 (Cua), the Y radius of the concave surface ranges from 5.1 to 9.7 cm. ——VV 1 screw-threaded joint Ad gle according to the element of protection AT where Y is the radius of the concave surface 0.1 cm.