JPS6342072B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of welding tubular members, and more particularly to a method of welding tubular members constituting side pocket mandrels used in oil wells using gas lift techniques.

A typical side pocket mandrel has a window on the side of a long tubular member, and the side pocket receptacle body is welded into the window.The receptacle hole is located in the mandrel to allow reception of a flow control device, and a portion of the receptacle body has a window. It has a lateral communication port that projects outward and guides fluid flow between the ceptacle hole and the outside of the mandrel. In this structure, a portion of the weld extends in the longitudinal direction of the mandrel. The US patent numbers for this example are:

2824525, 2948341, 3412806, 3666012,
2942671, 3040814, 3606393, 3727684, 3741299,
3827489, 3994339, 4106563, 3802503, 3827490,
4030543, 4106564, 3807498, Re 29870,
4031954, 4135576, 3807499, 3874445, 4034806,
4146091 Some side pocket mandrels utilize full circumference butt welds to join opposing tubular members. Examples of this are U.S. Patents 3788397 and 3827490.
No. 4135576 and No. 4146091. However, this full circumference weld is simply a butt weld, which joins the ends of the tubular member.

Some side pocket mandrels have a deflector device that extends above the receptacle hole to allow normal in-mandrel oil well tools to return to the mainstream passageway, prevent them from becoming jammed in the side pocket receptacle, and also allow flow control devices to enter the receptacle hole. guide and facilitate installation. Some deflectors are integral with the receptacle body and some are welded to the top end. Most deflectors are welded to the receptacle body, resulting in larger windows and longer seams welding the receptacle body.

The mandrel described above has been used for many years and has experienced many failures. Most failures occurred in longitudinal structural welds. Structural welds refer to weld seams that form the structural members of the side pocket mandrel. This structural weld is stressed by forces based on tensile, circumferential, and torsional loads acting on the mandrel as well as pressures inside and outside the mandrel. Structural welds include plug welds.

The above-mentioned weld failure is significant in the case of mandrels with non-circular cross-sections. Non-circular mandrels include oval and rectangular shapes and have been used for a long time, but in recent years
For 10 to 15 years, most mandrels are non-circular.
The advantage over circular mandrels is that two mandrels can be installed side by side and lowered side by side into a small well casing. If the casing size is constant, a large mandrel can be used in a dual well if it is non-circular.

When there are longitudinal structural welds in the walls of side pocket mandrels, particularly non-circular mandrels, high internal or external pressures create a tendency for the side walls to expand or contract. This expansion and contraction movement of the mandrel creates significant stresses in the longitudinal weld. Regarding this longitudinal weld, it is extremely difficult to (1) ensure that there are no notches where the inner wall of the mandrel meets the outer wall of the receptacle body, and (2) ensure that the weld completely reaches the inner surface of the wall. .

Additionally, many side pocket mandrels secure the deflector to the mandrel by plug welding. Similarly, many mandrels have a locating sleeve for positioning and orienting the pickover tool, and this sleeve is also often welded to the mandrel by plug welding. Plug welding is often used in the manufacture of side pocket mandrels, but there are few patents. US patent as an example
There is number 3827490.

Plug welding also causes many failures. This welding process involves welding deflectors, locating sleeves, etc. to the mandrel inner wall through holes in the mandrel wall. This hole is similar to a window, and at least a portion of the weld seam surrounding the window is longitudinal with respect to the mandrel. Therefore, it appears that the damage occurring to the plug weld is due to the same reasons as the damage occurring to the window. Although the size of the hole in the plug weld is smaller than that of the window weld, the notch effect of the weld is approximately the same.

The receptacle body shown in U.S. Patent No. 3,606,393 is particularly large in size, and the purpose is to strengthen the window part and prevent damage to the window.The reason why the material mass of the receptacle body is large is to prevent deformation due to welding, but the notch effect does exist. However, the pressure causes outward or inward deformation of the wall, which does not prevent damage.

Deformation and distortion of the mandrel due to welding is a problem in manufacturing side pocket mandrels.
Shrinkage changes depending on the amount of weld metal deposited. Therefore, the distortion of the weld seam in the axial direction is greater when the seam is long than when it is short. Distortion is significantly greater when the seams are not opposite each other but close to one side of the mandrel, ie in the case of side windows, especially long narrow windows.

Stress induced in the mandrel by contraction of the weld seam can damage the mandrel;
This stress can be removed by normalizing the entire mandrel. However, this heat treatment does not correct the distortion and requires rebending in the opposite direction of the distortion. This rebending operation creates residual stresses in the mandrel, but generally does not leave any significant harm.

A mandrel can be put to practical use even if it has some stress, but it is desirable to completely remove stress because it tends to promote corrosion.

U.S. Pat. No. 3,086,593 includes a check valve in a flow path extending through a gas lift valve attached to an offset receptacle of a side pocket mandrel to prevent backflow. This type of check valve is widely used. In some cases, this type of equipment does not use a gas lift valve and only has a check valve. When this valve is removed from the receptacle, the side port is open, allowing fluid to flow in both directions.

In a known example, a check valve is installed in a flow path that communicates directly with the lowermost end of an offset receptacle of a side pocket mandrel. This check valve is non-removable and is effective even if the receptacle hole is empty.
This type of side pocket mandrel is less effective than a regular gas lift valve, so its use is limited. In this mandrel, the lower end of the receptacle hole communicates with the outside of the mandrel. In a typical mandrel, the lower end of the receptacle hole communicates with the main hole of the mandrel. A typical gas lift valve for a side pocket mandrel allows the lift gas to enter the side of the valve and exit through the bottom end into the bottom of the receptacle hole. In a conventional side pocket mandrel, the receptacle hole is always drained and a gas lift valve is easily installed.
The lower end of the receptacle hole communicates with the outside of the mandrel,
With the mandrel that installs the check valve in this communication path,
The liquid collects in the receptacle hole and the check valve prevents drainage, making it difficult to install gas lift valves etc. due to the stagnant water.

There are no known techniques for attaching check valves to the side ports of side pocket mandrels. This lateral port communicates directly with the receptacle hole at a midpoint between the top and bottom of the receptacle hole. The lateral ports can be blocked by upper and lower mounted devices.

The present invention eliminates the above-mentioned known problems and drawbacks.
Provided is a method for welding tubular members, particularly tubular members comprising side pocket mandrels, in which longitudinal structural weld seams are completely eliminated, including window and plug welds, with minimal distortion and rebending. To create a product that is easy to manufacture, strong, and less prone to damage.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a new method for manufacturing a side pocket mandrel, in which a fully open, full-through main hole is machined to form an integral main body part, and a receptacle hole parallel to the main hole is machined into the main body part. The upper body is formed with a device for connecting to the oil country tubular goods at the lower end thereof, and has a main hole through which the entire passage passes, a curved surface portion for operating the kickover tool above the receptacle hole, and an oil country tubular connection device at the upper end. The main body part and the main body part are welded together by outer circumferential welding.

Another object of the present invention is to provide a method for manufacturing a side pocket mandrel as described above, in which the lower part of the main body is formed as a separate member, and the lower body is provided with an all-through main passage and an oil country pipe connecting device at the lower end. The lower body part is welded to the main body part by outer circumferential welding.

Another object of the invention is to provide a method for manufacturing a side pocket mandrel as described above, which comprises: a locating sleeve having a locating slot; a stop shoulder at the upper end of the slot; and a guide surface formed on a lower surface of the slot and sloping upwardly toward the slot. The positioning slot is inserted above the curved surface of the upper part of the upper body, and the upper edge is welded or brazed to the upper body, the welding being done from the upper opening of the upper body and the brazing being done. This should be done inside the furnace.

Another object is to form a locating sleeve having a locating slot and a guide surface below the slot and sloping upwardly toward the slot, the locating sleeve being attached to the lower body. The sleeve is inserted into the main body and welded at a position surrounding the main passage, and the sleeve is welded from the upper opening of the lower body before welding the lower body to the main body.

Another object of the present invention is to form a deflector device in the above-described method of manufacturing a side pocket mandrel, and to position the deflector device on the inner wall of the upper body portion above the receptacle hole, and to move the oil well tool away from the receptacle hole and toward the main passage. Welding is performed at a position extending down the main passageway, and this non-structural welding is performed through the opening of the upper body portion before welding to the upper body portion.

Another object is to provide a side pocket mandrel of the type described above with a check valve device that prevents backflow through the side port even when there is no flow control device in the offset receptacle hole, and the side port is located outside the side pocket mandrel. and the intermediate portion of the receptacle hole are communicated with each other.

Another object of the present invention is to provide a cartridge type check valve for a side pocket mandrel that is inexpensive to manufacture and easy to install and remove.

Another object is to provide a side pocket mandrel of the type described above with the possibility of easily converting the check valve to both outward flow blocking and inward flow blocking modes.

Another object of the present invention is to provide a method for butt welding the ends of two tubular members, such as a side pocket mandrel body, by circumferential welding, in which the weld reaches the inner surface of the tube, has high strength, and has a high strength. The purpose is to ensure that the main hole dimensions of the tube are not obstructed by weld metal.

Embodiments and drawings illustrating the present invention will be described.

1A-5, a side pocket mandrel 20 according to a first embodiment of the present invention is shown.
The machined main body portion 20a and upper body portion 20b of the mandrel 20 are permanently fixed together by a peripheral weld 21. The mandrel is attached to a string of oil country tubular goods by threaded portions 22 and 23 at the upper and lower ends of the mandrel.

The mandrel 20 has a well-known function, and the main passage 2
5 extends to the full length and passes the oil well tool through it. The side pocket 26 is located away from the main passage 25 and forms a space for operating a kickover tool (not shown). The receptacle hole 27 extends along the main passage 25 and opens upward into a pocket 26 for receiving a flow control device (not shown). The lower end of the receptacle hole 27 communicates with the main passage 25 through a horizontal passage 28;
The intermediate portion communicates with the outside of the mandrel by a lateral port 29.

Mounted on the mandrel 20 is a well-known positioning device, such as a positioning sleeve 31. sleeve 3
1 has a regular locating slot, top shoulder 3
3. It has a lower guide surface 34 for positioning a conventional positioning type kickover tool. The tool normally operates against a downwardly directed shoulder 33 at the upper end of the slot 32. The passage through the positioning sleeve is fully open. The guide surface 34 is therefore at the outer end of the full aperture.

The mandrel has deflector devices, such as deflectors 35, 36, which guide a flow control device (not shown) over the kickover tool inside the mandrel through oil country tubular goods (not shown). Additionally, the deflector deflects other well tools passing through the mandrel into the main flow path 25 in a known manner.

Receptacles, locating sleeves, and deflectors are generally well known.

As shown, the mandrel 20 has a generally elliptical cross-section and is formed with opposing flat portions 37, 37a and opposing semicircular side portions 38, 39 as shown in FIG. The mandrel can be circular or other cross-sectional shapes. However, elliptical mandrels can be placed side by side in parallel wells or can be passed through a casing of the required dimensions. Thus, an oval mandrel can use a smaller diameter casing or a larger diameter tube, other things being the same.

The main body 20a of the mandrel 20 is fabricated from a long, unitary main body blank. The blank can also be circular or other non-circular rather than oval. The main body can also be manufactured by forging, casting, etc. A fully open main hole 41 is machined the entire length of the blank, and a receptacle hole 27 is machined into the blank to extend downwardly along the main hole 41. A small diameter portion 27a is formed at the bottom of the receptacle hole 27.
They can also have the same inner diameter. The lateral port 29 is machined as shown in FIGS. 1B and 2 to communicate the receptacle hole with the outside of the blank. If the upper and lower parts of the receptacle hole have the same inner diameter, the lateral port 29 has a slightly larger diameter, and is a port of a flow control device (not shown) that is installed in the receptacle hole to control the flow through the port 29 and the lateral passage 28. and port 29. If the holes 27 and 27a are formed into stepped portions as shown in the figure, machining is easy and inexpensive.

An inner annular recess 44 is formed near the upper end of the receptacle hole to form a downwardly facing shoulder 45. Shoulder part 45
engages with a locking device (not shown) of the flow control device to lock the flow control device in place in the receptacle hole 27.

Insert a milling tool with a diameter slightly smaller than the inner diameter of the main hole 41 into the main hole from the lower end, and
7 is moved laterally in the direction of the receptacle hole to form a communication path 28, thereby communicating between the receptacle hole 27 and the main hole 41. Main hole 4
1 can be communicated with the communication path 28, the receptacle hole 27, and the side porter 29 at a position outside the main body.

An internal thread 23 is cut at the lower end of the main hole to enable connection to an oil country tubular string (not shown).

Machining the outer shape of the lower end of the main body blank to create internal thread 2
3 and a concentric outer surface 47 to facilitate the use of tools to connect the mandrel and string. At the same time, a guide surface 48 is processed to guide the mandrel to avoid obstacles when lowering it into the oil well.

In order to weld the upper end of the main body 20a to the upper body 20b, the necessary joint surfaces shown in FIG. 6 are formed.
A flat part 51 and an outer slope part 5 are provided at the upper end of the main body 20a.
2, an inner annular surface 53, and an inner inclined surface 54.

The illustrated fully open main passage passing through the side pocket mandrel means that the flow passage of the oil country tubular string attached to the mandrel and the main passage have approximately the same inner diameter;
This means that ordinary oil well tools that run through oil country tubing run through the mandrel. For example, if the inner diameter of what is commonly called 23/8 inches is 5.07 cm (1.995 inches) and the drift diameter is 4.83 cm (1.901 inches), the fully open dimension is 4.76 cm (1.875 inches) or more. The reason for this is that all normal well drilling tools that pass through this oil country tubing will pass if it is 1.875 inches or larger.
The main hole and main passage of the side pocket mandrel described here, for example, the main hole 41 of the main body 20a, are fully open, and the inner diameter is larger than the minimum dimension for fully opening.
Drift diameter greater than 4.76 cm (1.875 inches) required to pass well tools. This hole is also referred to as "unobstructed".

In US Pat. No. 4,135,576, an upper body is welded to an integrally formed main body through a peripheral weld. As stated very simply in the specification and evident in the drawings, the main bore of the main body is significantly narrower and significantly smaller than the drift diameter of the oil country tubular string. To this end, separate bypass passages are provided to accommodate the large flow rates of the flow control devices in the receptacle holes.

The main body shown in US Pat. No. 3,040,814 has two halves welded together by a longitudinal weld. This is not stated in the specification.

The perimeter weld of U.S. Pat. No. 3,412,806 is shown in FIG. 35, which is a cross-sectional view taken along line 35--35 in FIG. In FIG. 12, the weld includes not only the outer periphery but also the longitudinal section, which are interconnected by four arc-shaped sections.

When the main body 20a is formed by casting or forging an integral main body blank, a combination structure in which the main hole and the receptacle hole are formed inside can also be used. In this case, each hole only requires finishing. Both the receptacle hole and the main hole require finishing. If the precision of the casting or forging is good, the main hole does not require finishing and can be used as cast or forged, reducing processing costs. The savings in machining costs are greater than the cost of precision casting and forging.

The upper body portion 20b is made of a tubular material having the same cross-sectional shape as the main body portion 20a. The illustrated mandrel is oval in cross-section, with flat sides 37 as shown in FIGS.
37a. It can also be made of material of other shapes, for example circular cross-section.

To manufacture the upper main body part 20b, the upper end of the tube having an elliptical cross section shown in FIG. It is on the same axis as the passage 25, and is the main passage of the entire length of the mandrel.

The upper end of the small-diameter end 61 has the required outer diameter for a pipe joint, the hole 62 has a predetermined inner diameter, and the internal thread 22 is cut at the upper end.

The lower end of the upper body portion 20b can be welded like the main body portion 20b. As shown in FIG. 6, a flat portion 71, an outer sloped portion 72, an inner annular recess 73, and an inner sloped portion 74 are formed in the same manner as the main body portion.

Deflectors 35 and 36 are welded before welding both main body parts 20a and 20b. Deflector 35
is inserted into the lower end of the upper main body part 20b, at a predetermined distance from the lower end, and on the same axis as the receptacle hole,
Welding is performed by applying welding beams 74 along both edges as shown. It can also have a three-sided edge. This weld has a small volume and a small penetration depth, so there is almost no distortion.

The deflector 35 has a flat section 76 and a curved section 77 as outwardly facing vertical side walls, which match the inner wall of the mandrel at the position where the deflector is to be welded;
It is also easy to align with the receptacle hole for welding. The inner wall of the deflector is a concave surface 78,
Vertical ribs 79 are included to guide the well flow control device into the receptacle bore 41 . The deflector is sloped downwardly and inwardly at 80 to guide the guide device into the receptacle. Furthermore, deflector 3
5 is sloped downwardly and inwardly relative to the main passageway 25 to direct conventional oil well tools from the receptacle hole 27 to the main hole 41 . Oil well tools are typically too large in diameter to pass between deflectors 35 and 36.

The other deflector 36 is a mirror image of deflector 35, as shown in FIG. 5, and is mounted similarly to deflector 35, with both deflectors cooperating to perform the function described above.

The positioning sleeve 31 is shown in FIG. The locating sleeve 31 is cylindrical and has a downwardly directed shoulder 33 at the upper end of the locating slot 32. Shoulder part 3
3 blocks off all or part of the top of the slot 32. The guide surface 34 of the positioning sleeve is located in the slot 3
2, and slope toward the bottom of the slot as shown in the figure.

The positioning sleeve 31 is welded before or after welding the upper main body portion. Positioning sleeve 31
is inserted into the upper end of the upper body portion 20b, and the curved surface portion 26
Above, the slot 32 faces away from the receptacle hole and the shoulder 33 is a predetermined dimension above the deflector and receptacle hole.

As is well known, the position and orientation of the locating sleeve is determined by the particular kickover tool used with the particular side pocket mandrel, and by the type selected for use in the equipment. The positioning sleeve 31 within the mandrel 20 is oriented as desired and placed at the required distance from the deflector and receptacle holes according to the associated kickover tool.

To join the main body parts 20a, 20b, the joining surfaces are opposed to each other, and the alignment ring 84 is inserted to connect the upper and lower side surfaces of the outer flange 85 to the main body parts 20a, 20b.
the flat parts 51 and 71 of the The inner side 84a of the centering ring 84 is approximately semicircular. The ring is formed from wire of the desired cross section. The wire is bent to match the shape of the end face of the main body, such as circular or oval. A small gap (not shown) is left between the ends of the ring, and the ring is compressed slightly to fit into the hole at the end of the main body. Rings of this type are well known in steel forming and the like.

When the assembled state shown in FIG. 6 is reached and the main passages 25 are aligned on the same axis, both main body parts and the centering ring are fixed by tack welding at the outer periphery. Welding begins at the centering ring and extends all the way around the mandrel.
The outer slope portions 72, 52 of both main body portions are completely filled with metal in sequence. During this welding process, centering ring 84 melts and completely penetrates the weld, creating a joint of maximum strength. Although the inner surface of centering ring 84 melts during the welding process, it maintains its outer shape, and after completion, the inner surface has the shape shown in FIG. 7. The raised part is completely inwardly sloped surface 5
4 and 74 and does not protrude into the main passage 25, it does not obstruct the passage of oil well tools.

As shown, the weld 21 is purely circumferential, turning the mandrel at right angles to the longitudinal axis.
The welded portion 21 is one end of the integral main body portion 20a, and the main body portion serves as a support member for the mandrel and can withstand a large pressure difference from the inside and outside of the mandrel. The web 90 separating the main hole 41 and the receptacle hole 27 is extremely effective in strengthening the mandrel.
It is particularly effective in the direction where this strength is most needed. That is, it is effective in the direction perpendicular to the main axis of the elliptical tube and in the direction perpendicular to the plane passing through the centers of the main hole and the receptacle hole. Of course web90
will strengthen the mandrel even if the shape of the mandrel is oval, circular or other shapes. In all shapes, there is a web between the main hole and the receptacle hole.

Distortion occurs when the weld metal cools, but in the case of a circumferential weld between the two main bodies, the stress generated in the weld is evenly distributed around the mandrel outer circumference and balanced, so the distortion is small. This stress is removed by a heat treatment or normalizing operation, with little need for subsequent straightening of the mandrel.

Other types of joint surfaces between the body parts for performing circumferential butt welding are also possible. The shapes shown in FIGS. 6 and 7 are preferred, but the shape shown in FIG. 8 may also be used. In the case of high-performance mandrels that are subjected to large pressures and loads, it is desirable that the molten zone reach the inner surface.

There are various types of joint surfaces, but the type shown in Figure 8 is simple, does not require a centering ring, does not involve the complexity of assembly associated with a centering ring, and allows the molten part to easily reach the inner surface. . 27th, 29th, 30th, 31st
The figure shows an example of a bonding surface that can achieve the desired result.

In the example shown in FIG. 8, the upper body portion 20b' is the sixth
It has substantially the same shape as the upper main body portion 20b shown in the figure.
The lower end portion forms a flat portion 71a, an outer sloped portion 72a, and an inner annular surface 73a having an inner sloped portion 74a that becomes narrower upward and inward. The upper end of the main body portion 20a' is substantially similar to the upper end of the main body portion of FIG. 6, but has a shape that incorporates the centering ring of FIG. 6.
A small diameter portion 95 is provided at the upper end of the main body portion 20a' to engage the inner annular surface 73a of the upper body portion, and an upwardly facing shoulder portion 96 contacts the flat portion 71a of the upper body portion as shown in FIG. . The outer surface of the upper end of the main body portion forms an outer sloped portion 97 . The upper inner surface of main body portion 20a' forms a curved portion 98 similar to centering ring 84 of FIG. A concave recess 99 is formed below the convex curved portion 98 so that the inner protrusion 100 has the same shape as the centering ring. Even when the recess 99 is not provided, recesses similar to the recesses 53 and 54 in FIG.

During the welding process, the inward protrusions 98 melt and become part of the weld as shown in FIG.
The situation is similar to that shown in the figure when the centering ring 84 is melted and the welded portion extends to the inner surface.

The welding operation is performed by temporarily welding several points on the outer periphery in the same manner as described above, and then metal is sequentially deposited on the outer periphery of the mandrel to fill all the recesses formed by the slope portions 72a and 97 with weld metal. Next, remove the excess metal by polishing the 28th
The surface should be the same as the outer surface of the mandrel as shown in the figure.
To form a similar weld joint, both ends of the tubular member may be joined in the shape shown in FIG. 27. This joint is similar to the examples of FIGS. 6 and 8. The inner recesses 73a', 99' and the inner convex surface 98' are the same as in the example shown in FIG. 8, and the outer slope parts 72', 52' are the same as in the example shown in FIG. This welded joint is assembled, tack welded, and metal welded so that the welded part reaches the inner surface, the outer side is raised higher than the outer peripheral surface of the main body, and the welded part is ground flat as required. The complete weld joint is shown in FIGS. 7 and 28.

In order to achieve a good full penetration weld, other embodiments of the end shape of one of the tubular members, for example the main body section 20a of FIGS. 6 and 7, or the main body section 20a' of FIG. , 30, 31.

FIG. 29 shows a tubular member M, which includes a portion CB with a larger inner diameter, a first flat portion P1 at the end, and a cut outer diameter that is slidably fitted into the stepped portion 73a of the tubular member 20b' in FIG. A matching outer diameter portion D is formed. A second plane part P2 is formed surrounding the small protrusion P.
It is preferable that the outer slope portion C is formed by a dotted line Ca.

The tubular member Ma shown in FIG. 30 is processed in the same manner as the tubular member M shown in FIG. 29, except that an inner slope portion B is formed at the top and the first flat portion P1 is shaved.

The tubular member Mb in Fig. 31 is the tubular member in Fig. 30.
It has almost the same shape as Ma, but instead of the inner slope portion B, a curved surface portion R is formed with the inner surface of the first plane portion P1 shown in FIG. 29 as a curved surface. Tubular member in Figure 31
Mb is similar to the member 20a' in FIG.
There is no 9.

Although the outer surfaces of the tubular members Ma and Mb shown in FIGS. 30 and 31 can be formed into the sloped portions C shown in FIG. 29, it is preferable to form the sloped portions Ca.

When the tubular members M, Ma, and Mb are combined with the upper body part 20b in FIGS. 6 and 7 or the upper body part 20b' in FIG. 8 and the above-mentioned welding operation is performed, welding that reaches the inner surface as shown in FIG. 28 is achieved. Becomes a department.

In either case, the joint surfaces are shaped as required for the centering ring shown in Figure 6, or
9, 30 and 31, welding in an inert gas atmosphere results in a homogeneous weld that reaches the inner surface. results of the experiment,
Both tubular members must be filled with inert gas at least during the welding process of the base. The inert gas expels air containing oxygen from the pores of the tubular member to prevent scale from forming on the inner surface of the welded part, and the molten weld metal becomes a homogeneous welded part without scale, and the inner surface as shown in Figures 7 and 28. It forms a relatively flat bead like shape and does not protrude into the constant bore of the tubular member.

As an inert gas used as a protective gas in this welding operation, excellent results can be obtained with argon.

After the welded joints shown in Figures 6-8 and 27-31 are completed, inspection is performed, and the welds reach the inner surface.
It has excellent physical properties, almost no distortion,
It was found to be homogeneous.

The deflector and locating sleeve are attached to the mandrel with small volume welds with low seepage, resulting in little distortion of the mandrel. The deflector can also be secured by brazing if desired.

The manufacture of the side pocket mandrels described above does not use plug or longitudinal welds, which tend to weaken the mandrel. The strength of the welded part is the same as that of the mandrel body, and the strength of the full circumference weld that joins both body parts is high. This welding is not done in the longitudinal direction, the weld reaches all the way to the inner surface, and as the stresses are balanced, almost no distortion occurs.

Side pocket mandrels 20 with a locating sleeve at the upper end and side pocket mandrels without a locating sleeve have great utility in oil well equipment, where the flow control device in the receptacle hole can be installed by a kickover tool lowered into the oil well. Externally, and pull up using normal wire line. Side-pocket mandrels, which have a positioning device below the top of the receptacle hole, are typically used in submerged wells and require pump-down or through-flow line (TFL) techniques to lower and raise the kickover tool into the well. use Pump-down operations involve moving a string of tools through a tube string and flow line with a flow of pump liquid;
This pressure acts on piston elements forming part of each tool string. Mandrels used in pump-down wells are shown in Figures 9A and 9B.

9A and 9B illustrate a side pocket mandrel 120 according to a second embodiment of the invention. This mandrel 120 has a main body portion 120a machined in the same manner as the mandrel 20, and is joined to an upper body portion 120b by a welded portion around the entire circumference.

The main body portion 120a has a desired cross-sectional shape, for example, a 1B
It is machined from a long one-piece blank with a cross-sectional shape similar to the main body portion 20a shown. A fully open main hole 141 is machined longitudinally through the blank, and a receptacle hole 127 having a small diameter lower part 127a is machined along the main hole 141. The lateral port 129 communicates the outside of the mandrel with the receptacle hole 127 at a position directly above the small diameter portion 127a, and the communication path 1
28 communicates the lower end of the receptacle hole with the main hole 141.

A recess 144 formed near the upper end of the receptacle hole 127 forms a downwardly facing shoulder 145 that engages a locking device (not shown) of the flow control device to mount the flow control device within the receptacle hole and to secure the lateral port 1.
29.

The upper body portion 120b is similar to the upper body portion 20b of the side pocket mandrel 20 described above. The upper body portion 120b is molded from a tubular material;
The upper end 161 is made to have a small diameter and the internal thread 122 is cut. A stop shoulder, which will be described later, is provided near the top end. The mandrel 120 passes through a fully open main passage 125 and is connected to the oil country tubular string by upper and lower threaded portions 122, 123. At this time, the main passage 125 is continuous with the hole in the oil country tubular good and becomes a part of the oil country tubular hole.

The deflector 135 is welded to the inner wall of the upper body portion 120b at a predetermined position. This function is available in Mandrel 2
The explanation for 0 is similar.

The upper body portion 120b is welded to the main body portion 120a. This includes both main body parts 20a of the mandrel 20,
This is similar to the welding of 20b.

The small diameter portion 147 at the lower end of the main body portion 120a has the same dimensions as the oil country tubular coupling, and has an internal thread 12.
3 to the oil country tubular string. Internal thread 123 is formed at the lower end of main hole 141 .

A positioning device is formed in the main body portion. Although this locating device can be welded or brazed into the main hole 141 below the upper end of the receptacle hole as a locating sleeve, in the illustrated example, the locating device is integrally formed with the main body portion 120a. 9th
As shown in Figure B, the large diameter section 1 is located at the lower end of the main hole 141.
41a to form a downwardly directed guide surface 134 similar in shape to the guide surface 34 of the locating sleeve described above. This guide surface 134 is below the locating slot 132 and is oriented upwardly relative to the lower end of the slot 132. slot 13
The upper end of 2 coincides with the main hole 141 and does not form a downward shoulder. No shoulder is required to operate the pump-down kickover tool used with this mandrel. Shoulders can also be provided if desired. A downwardly facing shoulder 190 is provided on a ring 191 that engages on an upwardly facing shoulder 192 of the upper end of the mandrel 120 for actuating the pump down kickover tool. Ring 191 is welded to upper body portion 120b by welding portion 193, and this welding is performed from the open end of the upper body portion. The passage within ring 191 is a fully open passage, with shoulder 190 being outside the fully open hole.

The positioning device shown in US Pat. Nos. 4,106,563 and 4,106,564 is forged integrally with the upper portion forming the top of the mandrel and welded to the mandrel by a circumferential weld. The mandrel locating device shown in FIGS. 9A and 9B is integrally formed with the main body at the lower end of the mandrel and has no stop shoulder at the upper end of the locating slot.

The side pocket mandrel 120 shown in FIGS. 9A and 9B has the same function as the mandrel 20 previously described, with the difference that it is intended for submerged oil well applications and uses a pump-down kickover tool. The mandrel 120 is extremely useful for pump down operations in submerged oil wells.

Illustrated positioning guide surface 134, slot 132
A locating sleeve may be welded or brazed to orient the over tool without having the locating sleeve integral with the main body. For this purpose, the large diameter portion 141a at the bottom of the main hole 141 is extended upward, and the fourth
It is intended to accommodate a sleeve similar to the locating sleeve 31 shown. In this case, the large diameter portion 141a
The upper end is a slope, and the upper end of the positioning sleeve is also a slope, and the upper end of the positioning slot is a cam surface. A plurality of holes are provided in the wall of the positioning sleeve and the sleeve is plug welded to the wall of the large diameter section 141a. If this welding is done carefully, it will not interfere with the passage of the well tool through the locating sleeve, and the guide surface will not be uneven due to the welding.

10A, 10B, and 11 show a side pocket mandrel 220 according to another embodiment of the present invention, having a main body portion 220a, an upper body portion 220b, and a lower body portion 220c, which are welded at the outer periphery as shown.

The side pocket mandrel 220 allows the fully open main passage 225 to pass through, and has internal threads 222, 22 at both ends.
3. Attach to the oil country tubular string. The main passage 225 is continuous with the OCTG bore and becomes part of the OCTG bore when the mandrel is connected to the OCTG string.

The main body portion 220a is formed by machining from an integral long blank, and is formed by machining the main body portions 20a, 12
The processing is almost the same as that of 0a. Fully open main hole 241
is machined into the blank in the longitudinal direction, and the receptacle hole 227 is machined in parallel to the main hole 241. This receptacle hole 227 can also extend over only a portion of the blank, in which case the lower part of the hole 227 has a small diameter and forms a communication path similar to the communication path 28 of the mandrel 20. It is also possible to extend the receptacle hole between the ends of the blank. 1st
0B shows an example in which the receptacle hole passes completely through the main body portion 220a. The receptacle hole 227 is the receptacle hole 27, 12 of the mandrel 20, 120.
A lower small diameter portion like 7 is not formed. The receptacle hole 227 forms a large diameter portion 227a from the top to the bottom of the lateral port 229 to obtain a sufficient flow area and enable free flow between the lateral port 229 and a flow rate control device (not shown) in the receptacle hole. Make it. An annular recess 244 is machined near the top of the hole 227 to form a downward locking shoulder 245 that engages the locking device of the flow control device to secure the flow control device in place and connect the receptacle hole to the outside of the mandrel. The flow rate through the communicating lateral port 229 is controlled. The receptacle hole 227 and the main hole 241 pass through the blank, and their open lower ends communicate with each other within the lower lower body portion 220c. The main body portion 220a is processed so that its upper and lower ends can be welded to the main body portions 220b and 220c.

The upper body portion 220b has the same structure as the upper body portion 20b of the first embodiment. The structure, function, and characteristics are the same.

The upper body portion 220b has a side pocket portion 226.
Above, the upper end 261 has the same diameter as the oil country tubular coupling and the sleeve 231 is positioned within the hole 262.
Weld near the top end. After the deflector 235 is welded to the inner wall in the same manner as described above, the upper body portion 220b is welded to the main body portion 220a.

The lower body portion 220c of the side pocket mandrel 220 is similarly machined and formed from the same tubular material as the upper body portion 220b. The lower end of the lower main body part 220c has a small diameter part 247 having the same diameter as the oil country tubular coupling, and a hole is bored inside and an internal thread 223 is cut to connect it to the oil country tubular string. This screw is coaxial with the axis of the main hole 225 that runs the length of the mandrel. The upper end of the lower body part is processed for welding in the same manner as described above.

The main body portion 220a is assembled with the mandrel 220.
The joining surfaces of the upper and lower ends of the upper and lower main body parts 220b, 22
Abut against the end joining surface of 0c. The axes of the main passages 225 of the three body parts are aligned, and the outer peripheries are welded between the body parts in the same manner as described above, and the mandrel 2 is assembled.
Form 20. If desired, one body portion can be welded in combination and then the other body portion can be welded in combination.

As shown in the figure, upper and lower main body parts 220b, 220c
shall be made of tubular members of the same shape. In order to facilitate manufacturing and reduce machining losses, the upper and lower main body parts are forged as one tubular member, with a small diameter part 261 forged at one end of the tubular member and a lower small diameter part 247 at the other end.
are forged on the same axis. Process both small diameter parts, make the ends flat, make the small diameter part the required outer diameter,
A hole of the required inner diameter is drilled to allow a fully open main passageway to pass through the tubular member. It is then cut into two pieces, one of which will be the upper body and the other will be the lower body. There may also be two upper bodies or two lower bodies.
This manufacturing method is simple and inexpensive, but it is difficult to operate the die forging device unless it is a long member in order to grasp the material. Since some forging equipment cannot work with short lower body parts, it is better to forge the two body parts as one body and then cut them apart.

The side pocket mandrel 220 shown in FIGS. 10A and 10B, with or without the locating sleeve 31, has great utility in oil well applications and can be operated by lowering the required kickover tool into the well and using conventional wireline techniques. , it is possible to attach and detach the flow control device to the receptacle hole 227.

12A and 12B illustrate a side pocket mandrel 320 according to another embodiment of the invention. This mandrel 320 is similar to the side pocket mandrel shown in Figures 10A and 10B, but because it has a locating sleeve at the lower end and a retaining ring at the upper end, it is used primarily in submerged oil wells and for pump-down kickover tools. into the well as part of a pump-down tool string to install and remove the flow control device from the side pocket mandrel.

Mandrel 2 for the side pocket mandrel
A main body portion 320 similar to the main body portion 220a of No. 20
a, an upper body part 320b having the same shape as the upper body part 120b of the mandrel 120, and a lower body part 320c having a positioning sleeve added to the lower body part 220c of the mandrel 220;

Main body portion 320a is machined from a long, unitary blank similar to main body portion 220a described above. The main body portion 320a has a fully open main hole 341 and a receptacle hole 327 parallel to the main hole. Main hole 3
41 is a main passage 325 extending the entire length of the mandrel.
Continuous as part of. The large diameter portion 327a formed in the receptacle hole 327
7 is a portion of a lateral port 327 that communicates with the outside of the mandrel. A large diameter portion 344 is provided near the upper end of the receptacle hole 327 to form a downwardly facing shoulder 345 that engages a locking device (not shown) of the flow control device to lock the flow control device within the receptacle hole to lock the lateral port 329. control the flow through. The upper and lower ends of the main body part are processed so that they can be welded to other body parts all around.

Upper body portion 320b is similar to upper body portion 120b of mandrel 120 and performs the same function. A shoulder is formed at the small diameter upper end 361 to actuate the pump down kickover tool. The bore of cylindrical ring 391 defines a fully open passageway, and a downwardly directed internal annular shoulder 390 is formed on top of upwardly directed shoulder 392 of reduced diameter section 361 . The ring is welded or brazed by applying a weld 393 from the open end of the upper body. The ring 391 is secured to the upper body before or after welding the upper body to the main body around the entire circumference.

The lower body portion 320c is similar to the lower body portion 220c of the mandrel 220, but has a locating sleeve to mount a pump-down type kickover tool commonly used in pump-down or subsurface oil wells.

The main hole of the lower body part 320c is the lower body part 220
A shoulder portion 320d that is longer than c and slopes downward.
, and engages the beveled upper end 320e of the positioning sleeve 331.

The locating sleeve 331 is shaped as shown in FIG. 13 and is generally cylindrical with a locating slot 332 extending between its ends. The positioning guide surface 334 is the slot 3
32 and slopes upward in the direction of the slot. The sleeve 331 is installed around the main passage in the mandrel and is attached to the weld 3 shown in FIG.
Weld at 33. The sleeve 331 is connected to the slot 33
2 has a series of holes 335 on the opposite side to improve flow between the main hole and the lower end of the receptacle hole.

The side pocket mandrel 320 is welded all the way around, as in each of the above-described embodiments. This mandrel 3
Mandrel 20 has the same function as mandrel 120, its primary use is for submerged oil wells, and operates according to well known kickdown techniques.

In gas lift installations having multiple side pocket mandrels operated by a pump-down tool, a liquid, such as water, seawater, oil, etc., is circulated in order to move the pump-down tool through the oil country pipe.
In this case, there is a problem that the liquid circulation path is short-circuited due to the empty side pocket receptacle. This is likely to occur, for example, in a dual oil well shown in FIG.

In the example shown in FIG. 16, the oil well apparatus 400 includes a casing 401 and upper and lower sampling devices 402 and 403. The sampling device is the hole 405, 40 of the casing.
6 communicates with the casing hole 404.

Short and long oil country tubular string 4 inside casing 401
11, 412, the long string 411 communicates with the lower coloring device 403, and the string hole 414
communicates with the sampling device 403 via a hole 406. The lower end of the short string 412 is located at the upper sampling device 402, and the string hole 415 communicates with the upper sampling device 402 through the hole 405.

Valve 4 is installed at the upper end of oil country tubular strings 411 and 412.
17,418 are provided, and the respective distribution pipes 419,4
Connect to 20.

Upper and lower sampling devices 402, 4 for oil well patch car 422
Installed between 03, oil country pipe 411 and casing 4
01 is closed. Attach the oil well patcher 423 slightly above the upper sampling device,
Two oil country pipes 411, 412 and casing 401
Seal off the annular space between. The insulated upper and lower sampling devices 402, 403 communicate with oil country tubular strings 412, 411, respectively, and the flows from both sampling devices are not mixed.

The oil country tubular strings 411, 412 are in fluid communication via a transverse coupling member 424 such that liquid flowing down one string ascends through the coupling member 424 into the other string and circulates in a U-tube. Of course, during this circulation operation, the strings 411, 412 are closed below the connecting member 424 by the gate valves 425, 426 to prevent the circulating fluid from flowing into the sampling devices 402, 403.

The long string 411 has one or more side pocket mandrels, in the example shown upper middle lower side pocket mandrels 430, 431, 432.
, and upper and lower side pocket mandrels 433 and 434 are inserted into the short string 412.

The flow control devices in the side pocket mandrels 430-434 can be installed and removed in the normal manner using pump-down tools and techniques. However, since the position of the pump-down tool is primarily determined by volume measurements of the pumped fluid, if the side pocket mandrel receptacle in either string is empty, some of the pumped fluid will exit the side port. Flows outside the mandrel. Alternatively, lift gas may enter the string from within the casing through the side port, making the hydraulic volume measurement inaccurate. This inaccuracy may cause the tool to operate in the wrong position, e.g. in the wrong side pocket mandrel.
It will be a waste of time and money.

When a side pocket mandrel of the type described above is inserted into at least one of the oil country tubing during a gas lift in this type of oil well, a check valve prevents backflow or outflow from the side port. The check valve maintains the fluid pressure in the circulation system at a value greater than the pressure in the external space, and the check valve maintains the closed position to prevent outflow from the side port.

The side pocket mandrels 430-434 each have a plurality of lateral ports 430d, 431d, 432.
d, 433d, and 434d, and each port has a check valve to prevent liquid from flowing out from the port.

Side pocket mandrel 43 shown in FIG.
0 is similar to the side pocket mandrel 320 shown in FIGS. 12A and 12B except for the side port portion. It may also be similar to the side pocket mandrels of FIGS. 1-15.

The side pocket mandrel 430 shown in FIG. 17 has a plurality of lateral ports 430d each having a check valve shown in FIG. 18. Lift gas from outside the side pocket mandrel must enter the receptacle hole 427 through the side port. The total flow rate of the side port with check valve is equal to or greater than the total flow rate through the gas lift valve or other flow control device in the receptacle hole of the side pocket mandrel. This results in a good and highly practical device.

The main body 430a of the mandrel 430 communicates the outside of the mandrel with the receptacle hole 427 through a plurality of lateral passages 429. Passage 429 is provided with large inner diameter portions 460, 461 to accommodate the check valve device.

The check valve device 462 includes a check valve cage 464, a ball 465, and a check valve seat member 466, assembled as shown in FIG. As shown in FIG. 21, the flow passageway 467 of the check valve cage 464 has approximately the same dimensions as the mandrel body passageway 429 and defines an angled shoulder 469 with a large diameter section 468. The cage has cross slots 470a and 470b.
The slot extends above the shoulder 469. The cross slot thus forms a plurality of depending projections 471 and has an inwardly projecting boss 471a. The large diameter hole 468 is made slightly larger than the outer diameter of the ball, and the ball is normally in contact with the boss 471a.
The cruciform slot provides sufficient flow passage outside the ball.

The inner diameter of the central passageway 466a of the check valve seat member 466 is approximately the same diameter as the passageway 429 of the mandrel and forms a seat 466d in which the ball 465 engages. Shoulder 466 is provided by a counterbore in passage 466a.
form c. The large diameter portion 466b is the cage 46
Insert the upper end of 4 as shown in Figure 19.

The cage 464 and the seat member 466 are connected to the ball 465.
You can also glue them together. The check valve shall be made of the required material. The ball is preferably made of stainless steel. The gauge and the seat member are made of materials such as steel, stainless steel, and brass, and preferably of synthetic resin. Thermosetting synthetic resin, such as Philips' product name RYTON (polyphenylene sulfide)
Alternatively, VESPEL "SP-1" polyimide resin manufactured by DuPont is suitable. This material is suitable for injection molding, has sufficient strength and provides a good seal to the ball. A second type of polyphenylene sulfide is a thermoplastic resin for compression molding. This is also suitable for the seat member 466, but
Injection molding is more suitable for production.

A check valve device 462 consisting of a cage 464, a ball 465, and a seat 466 is fitted into the lateral passage of the mandrel as shown in FIG.
A ring 473 is inserted. The cage and seat are slidably engaged and are easy to handle. If they are made of synthetic resin, it is best to glue them together.

The cage of check valve device 462 engages hole 460, seat member 466 engages hole 461, and O-ring 473 engages the shoulder between holes 460, 461 to prevent leakage of the outer surface of the cage.

A washer-like member 475 having a passage 475a of the same size as the horizontal passage 429 is covered to support the seat member. This member 475 is made of a flexible non-metallic material,
The ball 465 is made of a material that can withstand the high internal pressure that presses the seat with a large force.

A retaining ring, such as a snap ring 476, is engaged in the annular recess 477 to retain the check valve arrangement. If the ball 465 is in the position shown in FIG. 19, no liquid will flow out of the mandrel from the receptacle hole 427. The ball closes passageway 466a. Flow from outside the mandrel into the receptacle hole moves the ball 465 to the off position through the seat passage 466.
causing a flow through a. When the ball contacts the internal boss 471a of the cage finger 471, the liquid freely passes outside the ball and into the slots 470a, 470.
b, enters the horizontal passage 429, and flows into the receptacle hole.

If check valves are attached to the above-mentioned side pocket mandrels, the system shown in Figure 16 will be able to maintain the hydraulic pressure in the OCTG string higher than the external pressure and keep the check valves of all the mandrels in the closed position. and the casing. Thus,
Accurate volume measurement of pumped liquid allows precise positioning of the pump-down tool.

A check valve similar to check valve device 462 can also be installed in the opposite direction. This check valve prevents flow from outside the side pocket mandrel into the receptacle hole.

FIG. 22 shows an oil well using a side pocket mandrel of the configuration described above. The oil well casing 500 shown in FIG. 22 passes through three layers of sampling devices: upper middle lower sampling devices 501, 502, and 503. Each sampling device communicates with casing bore 504 by bores 505, 506, 507. The oil country tubular string 508 is lowered into the casing, with the lower end near the lower sampling device 503. 1st police car 5
09 seals between the pipe and the casing to separate the lower sampling device 503 and the middle sampling device 502. The second packer 509a closes off the annular space between the tube and the casing and
2 and the upper collection device 501.

The first side pocket mandrel 510 of the oil country tubular string 508 faces the upper sampling device 501, and the second mandrel 511 faces the middle sampling device 5.
02. The required landing nipple 512 is placed opposite the lower sampling device 503.

An oil well tool (not shown), such as a jet adjustment device, is installed in the receptacle holes of the mandrels 510, 511 and landing nipple 512.

The liquid injected from the ground surface into the oil well is injected into the respective sampling devices 501, 502, and 503 through an oil country tubular string under the control of an injection adjustment device or the like. The purpose of injecting this liquid into the collection device is to maintain pressure in water-driven or recycling equipment;
It is also sprayed simply to treat liquid. In both cases, the pressure in the sampling device increases significantly.

Either side pocket mandrel 510,5
If the injection regulator is removed from 11, fluid from that sampling device may move up the oil country tubular string and into other sampling devices.

However, if a reverse check valve is attached to the mandrel, this inflow can be prevented.

A side pocket mandrel 600 with a reverse check valve is shown in FIG. The mandrel 600 has a shape in which a check valve is attached to the side port of the mandrel 20 shown in FIGS. 9A and 9B. Mandrel 600 can be used in wireline or pump-down equipment in a structure such as mandrel 430 in FIG. 17.

FIG. 25 is an enlarged view of the check valve of FIG. 24.
Check valve device 622 prevents liquid flow from outside mandrel 600 into receptacle hole 627 . Main hole 641 and receptacle hole 627 in mandrel body 600a
The lateral port 629 forming the receptacle hole 6
27 to the outside of the mandrel.

A large diameter portion 630 is formed outwardly of the lateral port 629 to engage a check valve device 662. A snap ring 676 is engaged with the inner annular recess 677 to hold the check valve device 662. Watashi-shaped disk 67
5 has a central passage 675a having approximately the same diameter as the passage 629, and supports a check valve cage 664 made of synthetic resin by inserting it between the check valve and the snap spring.

The check valve device 662 has a similar structure to the check valve device 462 described above. Hole 66 in check valve cage 664
Large diameter portions 669, 669a are provided on the seat member 6.
66 and the shoulder 669b holds the seat member 666 in place within the cage. The cage finger 670b has a boss 6 similar to the cage 464 described above.
71a.

The ball 665 is similar to the ball 465 described above, and after being placed in the cage 664, the seat member 666 is inserted into the hole 66.
9a. Seat member 666 contacts shoulder 669b. The seat 666 can also be secured to the cage 664. If the cage and seat are made of synthetic resin as described above, they are bonded together. In either case, the check valve becomes an easy-to-handle cartridge.

Seal ring, e.g. O-ring 663, into seat 66
6 to seal the space between the mandrel body 600a and the mandrel body 600a. Check valve device 662 only allows flow out of the receptacle hole.

The check valve device 662 can be installed as a reverse check valve as shown in FIG. 25, or it can be installed in the opposite direction as shown in FIG. 26 and used as a steady check valve to prevent outward flow as shown in FIG. You can also. That is, the check valve device 662 can be easily changed to the positions shown in FIGS. 25 and 26. Thus, it is preferable to prepare the material by processing the outer surface of the side port of the mandrel as shown in FIGS. 25 and 26 and preparing the check valve device 662. The mandrel can be supplied with or without a check valve, and the check valve can be switched between normal and reverse orientation as desired. Additionally, mandrels intended for one type of equipment can be repurposed for another type of equipment. Furthermore, the check valve can be easily installed, removed, and replaced in the opposite direction on site, and there is no need to send a mandrel to the factory.

The check valve devices 462, 622 can be manufactured easily and inexpensively in the form of a cartridge. It is preferable that the cage and the seat are made of synthetic resin and that stainless steel balls are inserted and bonded together.

In the side pocket mandrel according to the present invention, a side pocket receptacle hole is machined in an integral main body part parallel to the main hole, the upper body part is welded to the main body part by full circumference welding, and the upper body part has a curved surface part. is offset from the fully open main passage, the main passage passing straight through the mandrel, and the main hole in the main body portion forming a portion of the main passage. A portion connected to the oil country tubular string is formed at the lower end of the main body. This part can also be welded to the main body part as a lower body part. The mandrel is thus formed by two to three body parts.

Additionally, the mandrel of the present invention is strong due to the use of only full-circumference welds, can withstand large internal and external pressure differences, and has a solid integral body with a web between the main hole and the receptacle hole. The full-circumference weld used for mandrel joining creates little distortion because the stress is evenly distributed across the mandrel, is well balanced, and there is little need to rebend the mandrel. Full-circumference welding is welding that reaches the inner surface and does not obstruct the flow path within the mandrel. This mandrel is strong and inexpensive to manufacture.

A positioning device and a deflector device are attached to the mandrel as required, and welded into the mandrel.
Can be welded without using normal plug welding, which requires holes through the mandrel wall. The positioning device and deflector device are welded to the inner surface of the mandrel through holes in the end of the mandrel. Preferably, the welding is performed prior to the full circumference welding between the body portions of the mandrel. Welding is possible even after joining. The simple welding that secures the positioning device and deflector device has shallow penetration and does not cause distortion to the mandrel.

The locating device attached to the mandrel may be at the top or bottom end of the mandrel, depending on the technique used for attaching and detaching the flow control device. When using the wireline technique, the locating sleeve is the top of the mandrel. When using the pump down (TFL) technique, the positioning device is below the top of the receptacle hole.

Side pocket mandrel 120, 220, 3
20 main body parts 120a, 220a, 320a are the main body parts 20a of the side pocket mandrel 20.
Similarly, it is formed from an integral main body blank, and the blank is produced using techniques such as casting and forging. The main body portion produced by this method can also have the main hole formed by casting or forging. Depending on the precision of the casting or forging, the main hole may or may not be finished machined.

It is known to attach check valves to side ports of side pocket mandrels to control fluid flow through the side ports. A check valve prevents the fluid from flowing out of the mandrel, and installing the check valve in the opposite direction prevents fluid from flowing into the mandrel. Check valves can be easily installed in the field and can directly change inflow and outflow modes. The check valve is easily and inexpensively manufactured in the form of a cartridge, and is attached to the cage by inserting a seat member and a ball. The cage and seat member can be manufactured by injection molding of synthetic resin material, and are combined to form a cartridge type check valve. Check valves that can change direction are manufactured, stocked,
It becomes easier to manage shelves.

In order to permanently join the tubular members of the main body, a homogeneous weld that reaches the inner surface is formed, which has good quality and high strength, and is suitable for high pressure.

The positioning sleeve and tripling can be secured together in a furnace or in an induction furnace by brazing; brazing operations of this type are known. If desired, the teflector can also be secured by brazing. Securing the locating sleeve, trip ring, and deflector includes brazing and welding.

Although the present invention has been described in detail using preferred examples, the present invention can be modified in various ways, and the embodiments and drawings are merely illustrative and do not limit the invention.

[Brief explanation of the drawing]

A longitudinal sectional view of a side pocket mandrel according to a first embodiment of the present invention, taken together with FIG. 1A and FIG. 1B;
Figure 2 is a sectional view taken along line 2-2 in Figure 1B;
The figure is a cross-sectional view taken along line 3-3 of Figure 1B, Figure 4 is a side view of the positioning sleeve used for the mandrels of Figures 1A and 1B, and Figure 5 is a cross-sectional view taken along line 5-5 of Figure 1B. Cross-sectional view, Figure 6 is a partial cross-sectional view showing the alignment ring of the joint surfaces of both main body parts, Figure 7 is a partial cross-sectional view showing the joint surfaces of Figure 6 after welding, and Figure 8 is a partial cross-sectional view showing the joint surfaces of both bodies joined together. Partial sectional view showing before welding, Figure 9A Figure 9B
10A and 10B are together a vertical sectional view of the third embodiment, and FIG. 11 is a sectional view taken along line 11-11 of FIG. 10B. FIG. 12A and FIG. 12B are a longitudinal cross-sectional view showing the fourth embodiment; FIG. 13 is a side view of the mandrel positioning sleeve of FIGS. 12A and 12B;
Figure 4 is a sectional view taken along line 14-14 in Figure 12B;
Figure 15 is a sectional view taken along line 15-15 in Figure 12B, Figure 16 is an explanatory diagram of oil well equipment using a side pocket mandrel with a check valve, and Figure 17 is a side pocket mandrel of the equipment shown in Figure 16. 18 is a sectional view taken along the line 18-18 in FIG. 17, FIG. 19 is an enlarged view of a part of FIG. 18, FIG. 20 is an end view of FIG. 19, and FIG. 21 is an exploded view of the check valve in Figure 19, Figure 22 is an explanatory diagram of oil well equipment having a gas lift mandrel with a check valve,
Figure 3A and Figure 23B are a vertical sectional view of the side pocket mandrel of the equipment in Figure 22, Figure 24 is a sectional view taken along line 24-24 in Figure 23B, and Figure 25 is a partially enlarged view of Figure 24. Figure 26 shows the check valve in Figure 25 installed in the opposite direction, Figure 27 shows the check valve in Figure 8 installed in the opposite direction.
28 is a partial sectional view showing a modification of FIG. 7; FIG. 29 is a partial enlarged sectional view showing a modification of the joint surface between the main body parts; FIG.
The figure is a sectional view showing a modification of FIG. 29, and FIG. 31 is a sectional view showing a modification of FIG. 29. 20,120,220,320,430~43
4,510,511...Side pocket mandrel, 20a, 120a, 220a, 320a...
Main body part, 20b, 20b'120b, 220b,
320b... Upper body part, 25, 61, 125,
225, 325... Main passage, 26, 226... Side pocket, 27, 127, 227, 327,
427... Receptacle hole, 29, 129, 22
9,329,430d to 434d, 429... side passage, 31,231,331... positioning sleeve, 34,134,324... guide surface, 35,3
6,135,235,335...Deflector, 4
1,141,241,341,441...main hole,
51, 71, 71a...plane part, 52, 72, 7
2a, 97, 52', 72'...outside slope part, 5
3, 73, 73a...inner annular recess, 54, 7
4,74a...Inner slope portion, 84...Centering ring, 90...Web, 95...Small diameter portion, 96...
...Upward shoulder, 98, 98'...Inward convex surface, 9
9, 73a', 99'...Inner concave part, 220c,
320c...lower main body part, 400...oil well equipment,
401,500...Casing, 402,40
3,501-503... Collection device, 411,41
2,508... Oil country tubular string, 462,66
2...Check valve device, 464,664...Cage,
465,665... Ball, 466,666...
Seat member.

Claims (1)

[Claims] 1. A method of joining a pair of tubular members in a coaxial relationship by circumferential welding, comprising: a. a first tubular member 20 of the pair of tubular members;
The end of b' is machined to form a flat end face 71a perpendicular to the longitudinal axis, and the hole at the faceted end of the first tubular member b is widened to form a flat end face 71a at a position away from the faceted end. An internal recess 7 having an inclined surface 74a that contracts inward at
3a, and c chamfering the faceted end of the first tubular member from the outside to leave a narrow portion on the flat end surface of the first tubular member, so that the pair of tubular members are brought together for welding. When the narrow portion is connected to the second tubular member 2
0a', d chamfering the end of the second tubular member to form a first flat surface, e reducing the outer dimension of the first flat surface to form a second flat surface; a second plane 96 parallel to the first plane forming a short extension 95 on the end of the tubular member and surrounding the extension;
f forming a hole in the faceted end of the second tubular member and dimensioning the extension to fit substantially closely into an internal recess of the first tubular member; internal recesses 99, 9 having sloped surfaces that contract inwardly away from the ends;
g chamfering the end of the second tubular member from the outside to reduce the width of the second plane; h The pair of tubular members are aligned so that the flat end surface left on the first tubular member and the second plane of the second tubular member are in full contact with each other, and the pair of tubular members are chamfering from the outside to form an external recess consisting of an inwardly contracting wall surrounding the pair of tubular members; i tack welding at intervals around the joined tubular members; Welding the paired tubular members together by making a series of weld passes starting at the bottom of the outer recess and continuing until all of the outer recess is filled with weld metal, the extension of the second tubular member being welded together. A method characterized in that the weld is substantially melted during operation so that it leaves no protrusions within the holes of the pair of tubular members. 2. The method according to claim 1,
A method comprising chamfering an inner edge of the second tubular member and substantially removing a remainder of the first plane of the second tubular member. 3. The method according to claim 1,
A method comprising rounding an inner edge of the second tubular member and substantially removing a remainder of the first plane of the second tubular member. 4. A method according to any one of claims 1 to 3, comprising the step of removing excess weld metal to the same height as the outer surfaces of the pair of tubular members. . 5. In the method according to any one of claims 1 to 3, the chamfering from the outside of the pair of tubular members is formed by the chamfering when the tubular members are combined. A method characterized in that the external recess is shaped so that it has a profile consisting of an inwardly contracting slope connected to a substantially flat bottom by a curved line. 6. The method according to claim 5,
A method comprising the step of removing excess weld metal to the same height as the outer surfaces of a pair of tubular members. 7. In the method according to any one of claims 1 to 6, one of the pair of tubular members
A method characterized in that one of the tubular members constituting the side pocket mandrel is provided with a main hole and a receptacle hole parallel to the main hole.