JP2015021461A - Pressure container and manufacturing method of pressure container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure container that prevents residual stress from occurring in a welded part between a molding such as a panel board and a penetration member such as a pipeline, and thereby preventing a crack from occurring, and to provide a manufacturing method thereof.SOLUTION: A panel board 26 of an accumulator having inner and outer surfaces is molded by pressing a panel board (press step), to apply pressure on the inner surface of the panel board 26 (pressurization step). After that, to the panel board 26 to which pressure is applied, a pipeline 21 penetrating the panel board 26 is welded (weld step).

Description

  The present invention relates to a pressure vessel used for, for example, a compressor and a method for manufacturing the pressure vessel.

  Conventionally, as a pressure vessel, there exists a thing of Unexamined-Japanese-Patent No. 2011-80426 (patent document 1). As a method of manufacturing an accumulator as a pressure vessel, generally, a steel plate is pressed by a press device to be plastically deformed to form a mirror plate, a pipe is passed through the mirror plate, and the pipe and the mirror plate are welded. And the end plate is assembled | attached to the trunk | drum, and the accumulator is manufactured.

JP 2011-80426 A

  Incidentally, the accumulator is loaded with an internal pressure during use. When this internal pressure is applied, additional plastic deformation may occur in the accumulator. When this additional plastic deformation occurs, an excessive stress is applied to the welded portion between the end plate and the pipe, resulting in a residual stress, which causes cracks.

  Accordingly, an object of the present invention is to provide a pressure vessel and a pressure vessel that can prevent a residual stress from being generated in a welded portion between a molded product such as an end plate and a penetrating member such as a pipe, thereby preventing a crack from being generated. It is in providing the manufacturing method of.

In order to solve the above problems, the method for producing a pressure vessel of the present invention comprises:
A pressing step of pressing a steel plate to form a molded product of a pressure vessel having an inner surface and an outer surface;
A pressurizing step of applying pressure to the inner surface of the molded product;
A welding step of welding a penetrating member penetrating the molded product to the molded product loaded with pressure.

  According to the method for manufacturing a pressure vessel of the present invention, pressure is applied to the inner surface of a molded product formed by plastic deformation in a pressing step, and the penetrating member is welded to the molded product loaded with this pressure. For this reason, even if an internal pressure is applied to the molded product after the above-described welding, it is possible to prevent additional plastic deformation from occurring in the molded product and apply an excessive stress to the welded portion between the molded product and the penetrating member. Can be suppressed. Therefore, it is possible to prevent the residual stress from being generated in the welded portion, improve the fatigue strength of the welded portion, and prevent the occurrence of cracks.

Moreover, in the manufacturing method of the pressure vessel of one embodiment,
Between the pressing step and the pressurizing step, a pre-welding step of pre-welding the pipe as the penetrating member to the molded product is provided
The welding step is a step of re-welding the pipe to the molded product by melting the welded portion between the molded product and the pipe again.

  According to the above-described embodiment, the pipe is pre-welded to the molded product before the pressurizing step. Therefore, in the pressurizing step, gas or liquid can be easily introduced into the molded product using the pipe, and the molded product It is possible to easily apply pressure to the inner surface. Further, since the welded part between the molded product and the pipe is melted again and the pipe is welded again to the molded product, even if residual stress is generated in the welded part, the residual stress can be reliably removed.

Moreover, in the manufacturing method of the pressure vessel of one embodiment,
The molded product is an end plate.

  Moreover, the pressure vessel of this invention has the said end plate.

  According to the pressure vessel having the above configuration, since the end plate is provided, it is possible to prevent the occurrence of cracks in the welded portion between the end plate and the penetrating member during use.

  According to the pressure vessel manufacturing method of the present invention, since the penetration member is welded to the molded product after additional plastic deformation of the molded product, residual stress is generated in the welded portion between the molded product and the penetration member. Generation | occurrence | production can be prevented and it can prevent that a crack generate | occur | produces.

  Moreover, according to the pressure vessel of this invention, since it has the said end plate, it can prevent that a crack generate | occur | produces in the welding part between an end plate and a penetration member at the time of use.

It is a simplified front view showing one embodiment of the compressor of the present invention. It is a figure for demonstrating 1st Embodiment of the manufacturing method of the accumulator of this invention. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating 2nd Embodiment of the manufacturing method of the accumulator of this invention. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating 3rd Embodiment of the manufacturing method of the accumulator of this invention. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator. It is a figure for demonstrating the manufacturing method of the said accumulator.

  Hereinafter, the present invention will be described in detail with reference to illustrated embodiments.

(First embodiment)
FIG. 1 shows a simplified front view of one embodiment of the compressor of the present invention. As shown in FIG. 1, the compressor includes a compressor body 1, an accumulator 2, and a band 3 that fixes the accumulator 2 to the compressor body 1.

  This compressor is, for example, a high-pressure dome type rotary compressor, and constitutes an air conditioner as an example of a refrigeration system together with a condenser, an expansion mechanism and an evaporator (not shown).

  The compressor main body 1 includes a cylindrical body portion 15, bowl-shaped end plates 16 and 17 provided at both ends of the body portion 15, and a discharge pipe 13 provided at the center of the end plate 16. A support base 11 is attached to the body portion 15. The compressor body 1 is connected to an accumulator 2 and the condenser (not shown). The compressor body 1 compresses the refrigerant gas sucked from the accumulator 2 to a high temperature and a high pressure, and discharges it from the discharge pipe 13 to the condenser.

  The accumulator 2 includes a cylindrical body portion 25 and bowl-shaped end plates 26 and 27 provided at both ends of the body portion 25, respectively. The accumulator 2 is connected to the evaporator (not shown). The end plate 26 of the accumulator 2 has two outlet pipes 21 communicating with the compressor body 1. The outlet pipe 21 of the accumulator and the compressor body 1 are connected by two connecting pipes 5. A band 3 is wound around the outer periphery of the body portion 25 of the accumulator 2, and both ends of the band 3 are attached to the support base 11 of the compressor body 1. The accumulator 2 is fixed to the compressor body 1 by a band 3 and a support base 11.

  Next, the manufacturing method of the accumulator 2 as an example of a pressure vessel is demonstrated.

  2A to 2D are sectional views for explaining the first embodiment of the method for manufacturing the accumulator 2 of the present invention.

  First, a disk-shaped steel plate 20 as shown in FIG. 2A is pressed by a press working apparatus (not shown) to roughly form an end plate 26 as an example of a molded product as shown in FIG. 2B (pressing step). The end plate 26 is plastically deformed into a substantially bowl shape, and has an inner surface 26A and an outer surface 26B. Two cylindrical pipe insertion portions 26C projecting from the inner surface 26A toward the outer surface 26B are provided at the center of the end plate 26.

  Next, as shown in FIG. 2C, the end plate 26 is attached to the jig 30 for internal pressure load. The jig 30 includes a flat substrate 31 and an annular member 32 provided on the upper surface 31 </ b> A of the substrate 31. The annular member 32 has a recess 32 </ b> A provided at the center of the upper surface of the annular member 32. The peripheral edge of the end plate 26 is fitted into the recess 32 </ b> A, and the opening of the end plate 26 is sealed by the substrate 31.

  Next, the pipe 41 is fitted and attached to each of the pipe insertion portions 26C of the end plate 26, and high-pressure air is supplied from each of the pipes 41 to the inside of the end plate 26 via the pipe insertion portion 26C. With this high-pressure air, a pressure at least equal to the working pressure of the accumulator 2, preferably 1.5 times or more of the working pressure, is applied to the inner surface 26A of the end plate 26 (pressurizing step). At this time, a load is applied to the inner surface 26A of the end plate 26 outward in a direction orthogonal to the inner surface 26A.

  Next, the jig 30 and the pipe 41 are removed from the end plate 26. Then, as shown in FIG. 2D, an outlet pipe 21 as a penetrating member is inserted into the pipe insertion portion 26C, and the outlet pipe 21 and the end plate 26 are welded (welding process). Specifically, the outer peripheral part of the outlet pipe 21 and the end surface of the pipe insertion part 26C are welded. The welded portion 21A extends so as to surround the outer periphery of the outlet pipe 21.

  Next, the end plate 27 is manufactured in the same manner as the end plate 26. End plates 26 and 27 are attached to both ends of a separately manufactured body portion 25 by welding. In this way, the accumulator 2 is manufactured.

  According to the method of manufacturing the accumulator 2 of the above-described embodiment, pressure is applied to the inner surface 26A of the end plate 26 formed by plastic deformation in the pressing process, and the outlet pipe 21 is welded to the end plate 26 loaded with this pressure. Yes. For this reason, even if an internal pressure is applied to the end plate 26 after the above-described welding, additional plastic deformation is suppressed from occurring on the end plate 26, and an excessive stress is applied to the welded portion 21A between the end plate 26 and the outlet pipe 21. Can be suppressed. Therefore, it is possible to prevent the residual stress from being generated in the welded portion 21A, improve the fatigue strength of the welded portion 21A, and prevent the occurrence of cracks.

  Here, the end plate 26 receives a load in a direction parallel to the reciprocating direction of the plunger of the press device during molding. On the other hand, an internal pressure is applied to the accumulator 2 during operation, and the end plate 26 receives a load in an out-of-plane direction orthogonal to the inner surface of the end plate 26 during this internal pressure load. For this reason, the end plate 26 receives a load in different directions during molding and during internal pressure loading. Therefore, the inventor of the present application suppresses the occurrence of additional plastic deformation in the end plate 26 during operation by applying an internal pressure larger than the working pressure in advance during the manufacture of the end plate 26 to generate additional plastic deformation. The inventors discovered and found that it was possible to suppress excessive stress from being applied to the weld 21A.

  Moreover, according to the manufacturing method of the accumulator 2 of the said embodiment, in order to suppress that additional plastic deformation arises in the end plate 26 at the time of a driving | operation, it is not necessary to enlarge the thickness of the end plate 26, for example, and to improve rigidity. For this reason, it is possible to prevent the manufacturing cost such as the material cost and the processing cost from being increased by increasing the thickness to an unnecessary portion.

  Moreover, according to the accumulator 2 of the said embodiment, since it has the end plate 26, it can prevent that a crack generate | occur | produces in the welding part between the end plate 26 and the exit piping 26 at the time of use.

(Second Embodiment)
3A to 3E are sectional views for explaining a second embodiment of the method for manufacturing the accumulator 2 of the present invention. In the second embodiment, the same reference numerals as those in the first embodiment are the same as those in the first embodiment, and the description thereof is omitted.

  First, similarly to the pressing step shown in FIGS. 2A and 2B, the steel plate 20 as shown in FIG. 3A is pressed by a press working apparatus (not shown) to roughly form the end plate 26 as shown in FIG. 3B.

  Next, as shown in FIG. 3C, the outlet pipe 21 is inserted into the pipe insertion portion 26C, and the outlet pipe 21 and the end plate 26 are welded in advance (pre-welding step).

  Next, as shown in FIG. 3D, the end plate 26 is attached to the jig 30. A pipe 42 is attached to each of the outlet pipes 21 of the end plate 26. Then, high-pressure air is supplied to the inner side of the end plate 26 from each of the pipes 42 through the outlet pipe 21, and a pressure at least equal to the operating pressure of the accumulator 2 is applied to the inner surface 26 </ b> A of the end plate 26, preferably 1 .Load 5 times or more (pressurization process).

  Next, the jig 30 and the pressure pipe 42 are removed from the end plate 26, and the end plate 26 is heat-treated. Examples of this heat treatment include complete annealing and stress relief annealing. Specifically, the end plate 26 is placed in a furnace. In this furnace, as shown in FIG. 3E, heat is applied to the end plate 26 from a heat source 50 disposed on the left and right sides of the end plate 26. Then, the weld 21A is melted again by this heat, so that the pipe 21 is welded again to the end plate 26 (welding process).

  According to this accumulator 2 manufacturing method, the outlet pipe 21 is welded to the end plate 26 in advance before the pressurizing step, so that air can be easily introduced into the end plate 26 using the outlet pipe 21 in the pressurizing step. Thus, the pressure can be easily applied to the inner surface 26 </ b> A of the end plate 26.

  In addition, since the welded portion 21A between the end plate 26 and the outlet pipe 21 is melted again and the outlet pipe 21 is welded to the endplate 26 again, even if residual stress is generated in the welded portion 21A, this residual stress is reliably Can be removed.

(Third embodiment)
4A to 4E are sectional views for explaining a third embodiment of the method for manufacturing the accumulator 2 of the present invention. In the third embodiment, the same reference numerals as those in the second embodiment are the same as those in the first embodiment, and the description thereof is omitted.

  First, similarly to the pressing step shown in FIGS. 3A and 3B, the steel plate 20 as shown in FIG. 4A is pressed by a press working apparatus (not shown) to roughly form the end plate 26 as shown in FIG. 4B.

  Next, as shown in FIG. 4C, the outlet pipe 21 is welded to the end plate 26 in advance. Further, one end of the body portion 25 and one end of the end plate 26 are welded in advance to the other end of the body 25 and one end of the end plate 27 (see FIG. 1). This welded part 21 </ b> B extends so as to surround the outer periphery of both ends of the body part 25. In this way, the entire accumulator 2 is assembled (pre-welding process).

  Next, as shown in FIG. 4D, a pipe 42 is attached to each of the outlet pipes 21 of the end plate 26. Then, high-pressure air is supplied to the inside of the accumulator 2 from each of the pipes 42 through the outlet pipe 21, and the accumulator 2 is applied to the inner surface of the accumulator 2, that is, the inner surface 26 A of the end plate 26 and the inner surface 25 A of the body portion 25. A pressure at least equal to the working pressure, preferably 1.5 times or more of the working pressure is applied (pressurizing step).

  Next, the pressure pipe 42 is removed from the outlet pipe 21 of the end plate 26 and heat treatment is performed on the entire accumulator 2. Examples of this heat treatment include complete annealing and stress relief annealing. Specifically, the accumulator 2 is placed in a furnace. In this furnace, as shown to FIG. 4E, heat is applied to the accumulator 2 from the heat source 50 arrange | positioned at the right-and-left both sides of the accumulator 2. FIG. Then, by melting the welded portions 21A and 21B again with this heat, the outlet pipe 21 and the end plate 26, the end plates 26 and 27, and the body portion 25 are welded again (welding process). In this way, the accumulator 2 is manufactured.

  According to this accumulator 2 manufacturing method, the end plate 26 and the outlet pipe 21 are pre-welded before the pressurizing step, and the body portion 25 and the end plates 26 and 27 are pre-welded to assemble the entire accumulator 2. Therefore, in the pressurizing step, high-pressure air can be easily introduced into the accumulator 2 using the outlet pipe 21 without using a jig or the like, and pressure can be easily applied to the inner surface of the accumulator 2.

  Further, the welded portion 21A between the end plate 26 and the outlet pipe 21 and the welded portion 21B between the body portion 25 and the end plates 26, 27 are melted again, and the end plate 26, the outlet pipe 21, and the body portion 25, the end plates 26, 27 are melted. And weld again. Therefore, even if residual stress is generated in the welds 21A and 21B, the residual stress can be reliably removed.

  In addition, this invention is not limited to the above-mentioned embodiment. For example, the feature points of the first to third embodiments may be variously combined.

  In the first to third embodiments, the end plate 26 of the accumulator 2 is manufactured. However, another pressure vessel, for example, the end plate of the compressor body may be manufactured.

  Moreover, in the said 1st to 3rd embodiment, although the end plate 26 was manufactured, you may manufacture the other part of a pressure vessel, for example, a trunk | drum.

  In the first to third embodiments, high-pressure air is supplied to the inside of the end plate 26 or the accumulator 2, but other gases such as nitrogen and carbon dioxide, and liquids such as oil and water are supplied. The internal pressure may be applied.

  In the first to third embodiments, air is supplied through the insertion hole 26C of the end plate 26, but the insertion hole is sealed and air is supplied from the substrate of the jig to apply internal pressure. May be.

  In the first to third embodiments, the outlet pipe 21 is inserted into the pipe insertion portion 26C and the outlet pipe 21 and the end plate 26 are welded. For example, another penetrating member such as a terminal is used. The penetrating member and the molded product may be welded by being inserted into the molded product.

  In the second and third embodiments, the end plate 26 or the accumulator 2 is put in the furnace. However, any method can be used as long as the welded portion can be melted again to weld the pipe and the like again to the end plate. Good.

  In the third embodiment, high-pressure air is supplied from each of the pipes 42 to the inside of the accumulator 2 via the outlet pipe 21. However, the present invention is not limited to this. For example, before the outlet pipe is attached to the end plate, a pipe is attached to each of the pipe insertion portions of the end plate, and high-pressure air is supplied from each of the pipes to the inside of the accumulator via the pipe insertion portion. May be.

20 Steel plate 21 Outlet piping 21A Welded portion 26 End plate 26A Inner surface 26B Outer surface

Claims (4)

A pressing step of pressing the steel plate (20) to form a molded article (26) of a pressure vessel having an inner surface (26A) and an outer surface (26B);
A pressurizing step of applying pressure to the inner surface (26A) of the molded article (26);
And a welding step of welding a penetrating member (21) penetrating the molded product (26) to the molded product (26) under pressure. In the manufacturing method of the pressure vessel according to claim 1,
Between the pressing step and the pressurizing step, a pre-welding step of previously welding the pipe (21) as the penetrating member (21) to the molded product (26),
The welding step is a step of re-welding the pipe (21) to the molded product (26) by melting the welded part (21A) between the molded product (26) and the pipe (21) again. A method of manufacturing a pressure vessel, characterized in that: In the manufacturing method of the pressure vessel according to claim 1 or 2,
The method for manufacturing a pressure vessel, wherein the molded product (26) is a mirror plate (26).   A pressure vessel comprising the end plate (26) according to claim 3.

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