JP6353736B2 - Casing, and turbomachine and compressor provided with casing - Google Patents

Description

  The present invention relates to a casing, and a turbomachine and a compressor including the casing, and more particularly to a split-type casing.

  For example, a casing that is a casing of a compressor, pump, or other turbomachine that compresses gas or liquid is a substantially cylindrical casing in a plane that includes a central axis (axis), generally a horizontal plane in the vertical direction. There are a split-type casing that can be split, a barrel-type casing in which a disc-shaped lid is fixed to an axial end of a substantially cylindrical casing, and the like.

  The split type casing can be maintained by dividing the mating surface without removing the built-in rotary shaft, impeller and other members outside the casing, whereas the barrel-type casing has the built-in rotary shaft and blades. It is necessary to perform maintenance by pulling out a member such as a car in the axial direction. Therefore, the split type casing is excellent in maintainability compared to the barrel type casing. However, the split casing has a characteristic that fluid such as high-pressure gas or liquid is likely to leak from the mating surface.

  In recent years, there is a tendency for a compressor or the like to be required to have a high pressure or a large diameter, and accordingly, there is a high possibility that a high-pressure fluid leaks particularly in a split casing. Therefore, in the split type casing, a technique for preventing leakage of the high-pressure fluid from the mating surface is required in order to cope with an increase in pressure and an increase in diameter.

  As a background art of this technical field, for example, Patent Document 1 discloses that “having an upper casing and a lower casing divided by a dividing surface including the axis CL, and the flange 4 is fastened and fixed by a plurality of flange bolts 5 on the dividing surface. The flange 4 has a straight portion 2a along the body portion 10b, a curved portion 2b along the curved surface portion 10b, and a top vicinity 2c that is in the vicinity of the top 10c, The curve portion bolt interval L2 of the curve portion 2b is characterized by being wider than the straight portion bolt interval L1 of the straight portion 2a and the top bolt interval L3 of the apex vicinity portion 2c ”(see summary).

  Further, for example, in Patent Document 2, “in a fluid compressor which is a horizontally divided welded structure casing, an inner member for closing an end portion used for closing left and right side end portions of a flow path in an inner member is provided on its side surface. Thus, the sealing O-ring 23 is interposed on the contact surface between the side surface of the end closing inner member and the inner peripheral surface of the casing. (See summary).

  Further, for example, in Patent Document 3, “a gas turbine casing or the like is configured as a horizontally divided type flangeless casing 10. Bolt holes 7 are formed in the upper casing 1 in a tangential direction to the wall surface, and the lower casing 2 is connected to the lower casing 2. A screw hole having an inner screw 9b is provided in the inner periphery in the vicinity of the joint surface 3. A cylindrical sleeve 11 provided with an outer screw 9a to be screwed with the inner screw 5b is attached to the outer periphery of the bolt hole 7. The fastening bolt 5 is attached. The large-diameter portion 5c that comes into contact with the upper end surface of the sleeve 11 when the front-end fastening screw portion 5a is screwed into the fastening screw hole 5b of the lower casing 2 is described (summary). reference).

JP 2013-249771 A JP 2001-254697 A JP 2001-107922 A

  In the split type casing that can be divided in the vertical direction, flanges are formed on the upper casing and the lower casing on the upper side, and the flanges are brought into surface contact with each other at the mating surfaces and fastened by fastening members such as bolts. Composed.

  When the pressure (internal pressure) of the high-pressure fluid rises in the casing configured in this way, a force is applied in the direction of opening the upper casing and the lower casing, and the force and the distance from the casing inner surface to the bolt center axis A bending moment that is the product occurs. That is, a tensile load is applied to the fastening portion while receiving a bending moment in a direction in which the mating surface of the flange of the upper casing and the flange of the lower casing opens the mouth. The bending moment and the tensile load are superposed, and as the internal pressure increases, the surface pressure (compression surface pressure) generated by fastening the bolts on the mating surfaces of the flanges decreases, and an opening occurs on the mating surfaces. Normally, a sealing member such as a gasket is incorporated in the mating surface, and when the amount of mouth opening actually generated exceeds the mouth opening allowable value of the sealing member, the high-pressure fluid inside the casing is joined to the mating surface. May leak.

  The split casing generally includes a body plate portion that curves around an axis, and a side plate portion that bulges in a curved shape from an end portion in the axial direction of the body plate portion. Since the bolts for fastening the flange cannot be arranged at the top of the side plate where the mounting portion for the bearing that supports the rotating shaft is provided, the opening of the mating surface of the flange tends to increase near the top of the side plate. Therefore, in order to achieve high pressure and large diameter of the compressor or the like, it is important to suppress the opening of the mating surface of the flange, particularly the opening of the mating surface of the flange near the top of the side plate portion.

  In the technique described in Patent Document 1, in order to suppress the opening of the mating surface of the flange in the vicinity of the top portion of the side plate portion and in the vicinity of the center of the body plate portion, the installation interval of the fastening bolts in that portion is set to be different from that in other portions. Is also configured to be narrow. However, in this technique, the bolt center shaft needs to be separated from the inner surface of the casing to some extent so that the head of the bolt does not interfere with the outer surface of the side plate portion or the body plate portion. Depending on the shape, it may be difficult to reduce the bending moment that acts in the direction in which the mating surface of the flange opens the mouth.

  In the technique described in Patent Document 2, the side plate portion is formed of a disk that is a member different from the body plate portion, and the casing inner surface and the side plate portion formed by the cylindrical body plate portion are sealed using an O-ring. It is comprised so that it may do. However, in this technique, in order to maintain the rotating shaft and the like, it is necessary to pull out and remove the side plate portion in the axial direction, and the side plate portion itself also has an increased number of maintenance steps compared to a structure that can be divided vertically in a horizontal plane, for example. There are challenges.

  The technique described in Patent Document 3 is configured to form a bolt hole in a wall portion of a casing through which a bolt for fastening a vertically divided casing is passed. According to this, since the bolt central axis is close to the inner surface of the casing, it is considered possible to suppress the opening of the mating surface of the casing. However, in this technique, it is necessary to make the wall thickness of the casing wall larger than the bearing surface diameter of the bolt, and in order to obtain such a casing, a technique for processing a thick plate material is also required.

  The present invention has been made in consideration of the above-described prior art circumstances, and is a split-type casing with good maintainability that can suppress leakage of high-pressure fluid from the mating surface without increasing the wall thickness. It is another object of the present invention to provide a turbomachine and a compressor including a casing.

In order to solve the above-described problem, a casing according to the present invention includes a first casing and a second casing that can be divided by a mating surface formed on a plane including an axis, and the first casing and the second casing include A body plate portion that curves around the axis, and a side plate portion that bulges in a curved shape so that a position on the axis line is a top portion from an end portion of the body plate portion in the axial direction. An attachment portion for attaching a bearing that supports a built-in rotating shaft is provided on the top portion of the side plate portion, and the first casing is welded to the body plate portion and the side plate portion of the first casing to form the mating surface. The second casing has a second flange welded to a body plate portion and a side plate portion of the second casing to form the mating surface, and the first flange and the second furan Are in contact with each other at the mating surface and fastened and fixed by a plurality of fastening members, and welded to the body plate portion and the side plate portion of the first casing, and to the second casing. At least one of the welded surface of the second flange to be welded to the body plate portion and the side plate portion is perpendicular or inclined with respect to the mating surface.
A turbo machine according to the present invention includes the casing.
The compressor according to the present invention includes the casing.

  The casing manufacturing method according to the present invention is the casing manufacturing method, wherein welding is performed on a welding surface that is perpendicular or inclined with respect to the mating surface, of the first flange and the second flange. The plate is formed by cutting a flat plate material, a surface perpendicular or inclined with respect to the plate thickness direction of the plate material is used as the welding surface, and a surface parallel to the plate thickness direction of the plate material is used as the mating surface. It is characterized by.

  According to the present invention, it is possible to provide a split-type casing with good maintainability that can suppress leakage of high-pressure fluid from a mating surface without increasing the wall thickness, and a turbo machine and a compressor including the casing. it can.

It is a perspective view which shows the external appearance of the casing which concerns on 1st Embodiment of this invention. It is sectional drawing of the mating surface vicinity in the casing which concerns on 1st Embodiment of this invention. It is sectional drawing of the mating surface vicinity in the conventional casing as a comparative example. It is a figure which shows typically the deformation | transformation at the time of the internal pressure rise of the casing which concerns on a comparative example. It is the figure which looked at the upper casing of the casing concerning a 2nd embodiment of the present invention from the lower part. It is sectional drawing of the mating surface vicinity in the casing which concerns on 3rd Embodiment of this invention. It is an expansion perspective view near the top part of the side-plate part of the casing which concerns on 4th Embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
Note that, in the drawings shown below, the same members or corresponding members are denoted by the same reference numerals, and redundant description is omitted as appropriate. In addition, the size and shape of the member may be schematically represented by being modified or exaggerated for convenience of explanation.

[First Embodiment]
First, a first embodiment of the present invention will be described with reference to FIGS.
The casing according to the first embodiment of the present invention is suitable for being applied to a casing of a compressor, pump, or other turbomachine that compresses a fluid such as gas or liquid.

  FIG. 1 is a perspective view showing an appearance of a casing according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view of the vicinity of the mating surface in the casing according to the first embodiment of the present invention, specifically, a cross-sectional view taken along line AA or BB in FIG.

  As shown in FIGS. 1 to 2, the casing 1 includes an upper casing 1 a and a second casing 1 as a first casing that can be divided in the vertical direction on a mating surface 103 formed on a plane (here, a horizontal plane) including the axis CL. A lower casing 1b as a casing is provided. The casing 1 has a hollow cylindrical shape that is substantially circular when viewed from the extended line of the axis CL, and houses a mechanism portion (not shown) having members such as an impeller and a rotating shaft inside. Is.

  The upper casing 1a and the lower casing 1b are parallel to the axis line CL and curved around the axis line CL, and the positions on the axis line CL from the ends of the body plate parts 6a and 6b in the axis line CL direction are the tops. And side plate portions 7a and 7b that bulge into curved shapes. The curved surface here is, for example, a spherical surface or an elliptical spherical surface, but the shape is not limited as long as it is a curved surface shape that can withstand the pressure generated inside. A cylindrical body plate 6 is formed by the body plate portion 6a and the body plate portion 6b, and a substantially hemispherical side plate 7 is formed by the side plate portion 7a and the side plate portion 7b.

  And the top through-hole 11 as an attachment part which attaches the bearing 12 which supports the rotating shaft (not shown) incorporated in the casing 1 in the both ends of the casing 1, specifically the top part of the side-plate parts 7a and 7b. Is provided. A rotating member (not shown) such as an impeller is fixed to a rotating shaft passing on the axis CL.

  The lower casing 1b forms a lower part of the hollow casing 1, and a nozzle 3 for sucking and discharging fluid is appropriately formed. The nozzle 3 is not limited to the configuration formed on the lower casing 1b, and the nozzle 3 may be formed on the upper casing 1a.

  The upper casing 1a is formed in substantially the same shape as the lower casing 1b except for the nozzle 3, and the upper casing 1a and the lower casing 1b are overlapped to form a casing 1 so that their hollow portions face each other. As described above, a horizontal plane that divides the casing 1 in the vertical direction, that is, a plane where the upper casing 1 a and the lower casing 1 b are combined is referred to as a mating plane 103.

  The upper casing 1 a has an upper flange 4 a as a first flange that is welded to the body plate portion 6 a and the side plate portion 7 a of the upper casing 1 a to form the mating surface 103. Further, the lower casing 1b has a lower flange 4b as a second flange that is welded to the body plate portion 6b and the side plate portion 7b of the lower casing 1b to form the mating surface 103. At the mating surface 103, the upper casing 1a and the lower casing 1b are brought together so that the upper flange 4a and the lower flange 4b are in surface contact. Note that a seal member such as a liquid packing, gasket, or O-ring that normally prevents leakage of high-pressure fluid is sandwiched between the upper flange 4a and the lower flange 4b.

  As shown in FIG. 2, the upper flange 4a is formed with a plurality of through holes 4a1 through which the flange bolts 5 as fastening members are inserted toward the lower flange 4b so as to penetrate the upper flange 4a. The lower flange 4b is formed with a screw hole 4b1 into which the flange bolt 5 is screwed at a position corresponding to the through hole 4a1 of the upper flange 4a. Then, with the upper flange 4a and the lower flange 4b mated at the mating surface 103, the flange bolt 5 is inserted from the side of the upper flange 4a into the through hole 4a1 and screwed into the screw hole 4b1 formed in the lower flange 4b. To do. As described above, the upper flange 4 a and the lower flange 4 b are brought into surface contact with each other at the mating surface 103 and fastened and fixed by the plurality of flange bolts 5, thereby forming the casing 1.

  Here, the flange bolt 5 includes a stud bolt 5a and a nut 5b screwed onto the top of the stud bolt 5a. However, a hexagon bolt or a hexagon socket head cap bolt may be used instead of the stud bolt 5a and the nut 5b, or a through hole may be formed in the lower flange 4b in the same manner as the upper flange 4a and fastened with a bolt and a nut.

  As shown in FIG. 1, the casing 1 is formed with a top through-hole 11 penetrating in the axial direction around the axis CL at the top of the side plate portions 7a and 7b. The top through-hole 11 includes, for example, a bearing 12 that rotatably supports a rotary shaft (not shown) of an impeller housed in the casing 1 and a shaft seal device that prevents fluid leakage from the rotary shaft. 12a is attached.

  FIG. 3 is a cross-sectional view of the vicinity of a mating surface in a conventional casing as a comparative example. FIG. 4 is a diagram schematically illustrating deformation of the casing according to the comparative example when the internal pressure is increased.

  In the comparative example shown in FIG. 3, the body plate portions 6a and 6b and the side plate portions 7a and 7b manufactured by bending the plate material, and the upper flange 4a and the lower flange 4b cut out from the plate material (hereinafter also collectively referred to as the flange 4). ) On the surface parallel to the mating surface 103 of the flange 4 and on the opposite side of the mating surface 103 of the flange 4 so as to fill the joint portion indicated by reference numeral 100 in FIG. It is the structure welded by a certain welding surface 101a, 101b. The thickness of the flange 4 (the dimension in the direction perpendicular to the mating surface 103) is T, the inner radius of the casing 1 is R, the plate thickness (wall thickness) of the casing 1 is t, and the nut for tightening the stud bolt 5a. When the outer radius of 5b is r, the distance L from the inner surface of the casing to the bolt central axis is the following equation (1) from the condition that the nut 5b does not hit the outer surface of the body plate portion 6a or the side plate portion 7a. It is necessary to satisfy.

  From this equation (1), it can be seen that the distance L can be shortened by increasing the thickness T of the flange 4. For example, when the inner radius R of the casing 1 is 1250 mm, the plate thickness t of the casing 1 is 100 mm, the outer radius r of the nut 5 b is 50 mm, and the thickness T of the flange 4 is 200 mm, the distance L is calculated as 135 mm. In this case, if the thickness of the flange 4 is doubled as T = 400 mm, the distance L> 89 mm is calculated, and the distance L can be reduced to about 2/3 as compared with the case where T = 200 mm. Since the bending moment acting in the direction in which the mating surface 103 of the flange 4 opens the opening is proportional to the distance L, when the same flange bolt 5 is used and the same tightening force is used, the thickness of the flange 4 is changed from T = 200 mm to 400 mm. By increasing the value, the pressure resistance can be improved up to about 1.5 times.

  However, in the comparative example shown in FIG. 3, it is difficult to increase the thickness T of the flange 4 for the following reason. That is, in the comparative example shown in FIG. 3, the flange 4 is formed from a single plate so that the plate thickness direction of the plate used as the raw material is the same as the thickness direction of the flange 4 (direction perpendicular to the mating surface 103). It is cut out and welded to the body plate portions 6a, 6b and the side plate portions 7a, 7b at the welding surfaces 101a, 101b which are parallel to the mating surface 103 of the flange 4 and opposite surfaces. Generally, the maximum thickness of a steel plate material that is easily available in the market is about 230 mm. For this reason, in the casing according to the comparative example in which the body plate portions 6a and 6b and the side plate portions 7a and 7b are welded to the welding surfaces 101a and 101b which are parallel to the mating surface 103 of the flange 4 and opposite surfaces, the flange 4 It was difficult to make the thickness T of the sheet 230 mm or more. Therefore, it is difficult to shorten the distance L from the casing inner surface to the bolt central axis, and the bending moment acting in the direction in which the mating surface 103 of the flange 4 opens the opening cannot be sufficiently reduced.

  In the casing according to such a comparative example, as shown in FIG. 4, when the casing internal pressure rises, a force F is applied in a direction to open the mating surface 103 of the flange 4, and the force F and the bolt center axis from the casing inner surface. There is a possibility that a bending moment that is a product of the distance L and the compression surface pressure on the mating surface 103 of the flange 4 is reduced, and the mating surface 103 is opened.

  Therefore, in the present embodiment, as shown in FIG. 2, the welding surface 102a of the upper flange 4a welded to the body plate portion 6a and the side plate portion 7a of the upper casing 1a, and the body plate portion 6b and the side plate portion of the lower casing 1b. The welding surface 102 b of the lower flange 4 b welded to 7 b is configured to be perpendicular to the mating surface 103.

  In the present embodiment, the upper flange 4a and the lower flange 4b are formed by cutting a flat plate material, and the surfaces perpendicular to the plate thickness direction of the plate material are the welding surfaces 102a and 102b, and the plate of the plate material The casing 1 is manufactured by setting the surface parallel to the thickness direction as the mating surface 103. Here, the width W direction of the upper flange 4a and the lower flange 4b coincides with the plate thickness direction of the plate material as the material.

According to this embodiment, the body plate portions 6a and 6b, the side plate portions 7a and 7b, and the weld surfaces 102a and 102b of the flange 4 are divided into surfaces perpendicular to the mating surface 103 of the flange 4. Also in the casing 1 of the mold, the thickness T of the flange 4 can be increased so that the central axis of the flange bolt 5 as a fastening member can be as close as possible to the vicinity of the inner surface of the casing 1. In this way, the bending moment applied to the flange 4 can be reduced by bringing the flange bolt 5 close to the inner surface of the casing 1, and the pressure resistance performance of the casing 1 can be improved.
That is, it is possible to provide a split-type casing 1 with good maintainability and a turbo machine and a compressor including the casing 1 that can suppress leakage of high-pressure fluid from the mating surface 103 without increasing the wall thickness. .

  Moreover, since the surface parallel to the plate thickness direction of the plate material used as the material of the flange 4 is the mating surface 103, the surface opposite to the mating surface 103 of the flange 4 is the seating surface of the nut 5b. Even if it is about 200 mm, for example, the seating surface of the nut 5b can be sufficiently secured. Furthermore, since the thickness T of the flange 4 can be arbitrarily selected without depending on the plate thickness of the plate material as a material to be cut out, the thickness T of the flange 4 is set according to the pressure load in the casing 1. Can be adjusted.

  Note that only the upper flange 4 a is configured to be welded to the body plate portion 6 b and the side plate portion 7 b with a welding surface 102 a perpendicular to the mating surface 103 of the flange 4, and the lower flange 4 b is parallel to the mating surface 103. Further, the welding surface 101b (see FIG. 3) which is the opposite surface may be welded. When the nut 5b is seated on the lower flange 4b and the upper flange 4a is provided with a screw hole so that the upper and lower flanges are reversed, only the lower flange 4b is welded perpendicular to the mating surface 103 of the flange 4. The surface 102b is configured to be welded to the body plate portion 6b and the side plate portion 7b, and the upper flange 4a is welded to a welding surface 101a (see FIG. 3) that is parallel to the mating surface 103 and opposite to the mating surface 103. You may be comprised so that.

[Second Embodiment]
Next, referring to FIG. 5, the second embodiment of the present invention will be described with a focus on differences from the first embodiment described above, and description of common points will be omitted as appropriate. FIG. 5 is a view of the upper casing of the casing according to the second embodiment of the present invention as viewed from below.

  As shown in FIG. 5, the part welded to the side-plate part 7a among the upper flanges 4a of the upper casing 1a is comprised by the some linear part 105-107. On the other hand, a portion of the upper flange 4a of the upper casing 1a that is welded to the body plate portion 6a is composed of one straight portion 104. These straight portions 104 to 107 are divided and welded at the joint portion 108. The lower half of FIG. 5 shows the state after the inner diameter processing of the upper casing 1a and the processing of the through hole 4a1, and the upper half of FIG. 5 shows the inner diameter processing of the upper casing 1a and the processing of the through hole 4a1. The previous state is shown. Moreover, since the lower casing 1b has substantially the same configuration, illustration and description thereof are omitted.

  When the upper flange 4a is cut out from a plate material as a material, the plate thickness direction of the plate material is the width W direction of the upper flange 4a (see FIG. 2). In this case, the curved portion welded to the side plate portion 7a of the upper flange 4a cannot be cut out from a single plate material and used as it is. In addition, since the plate thickness becomes relatively large, it is difficult to bend the material cut out from the plate material. However, according to the second embodiment, the portion to be welded to the side plate portion 7a is constituted by the plurality of straight portions 105 to 106, and these are welded to the side plate portion 7a of the upper flange 4a. It is possible to easily form a curved portion. However, it is also possible to integrally form the upper flange 4a by bending a piece cut out from the plate material with a large processing machine.

  For example, when only the upper flange 4a is configured to be welded to the body plate portion 6b and the side plate portion 7b with a welding surface 102a perpendicular to the mating surface 103 of the flange 4, the side plate of the upper flange 4a The part welded to the part 7a may be composed of a plurality of straight parts 105 to 106, and the lower flange 4b may be cut out from a single plate and formed integrally.

[Third Embodiment]
Next, with reference to FIG. 6, the third embodiment of the present invention will be described with a focus on differences from the first embodiment described above, and description of common points will be omitted as appropriate. FIG. 6 is a cross-sectional view of the vicinity of the mating surface in the casing according to the third embodiment of the present invention.

As shown in FIG. 6, in the third embodiment, the welding surface 102 c of the upper flange 4 a welded to the body plate portion 6 a and the side plate portion 7 a of the upper casing 1 a is configured to be inclined with respect to the mating surface 103. ing.
On the other hand, the lower flange 4b is cut out from a single plate so that the thickness direction of the plate material used as the raw material is the same as the thickness direction of the lower flange 4b (the direction perpendicular to the mating surface 103). The welding surface 101b of the body plate part 6b and the side plate part 7b of the casing 1b and the lower flange 4b is configured to be parallel to the mating surface 103.
That is, here, only the upper flange 4a is welded to the body plate portion 6a and the side plate portion 7a at the welding surface 102c inclined with respect to the mating surface 103 of the flange 4, and the lower flange 4b of the lower casing 1b is welded to the mating surface 103. It is the structure welded by the welding surface 101b which is a surface on the opposite side. In the first embodiment, the thickness of the upper flange 4a of the upper casing 1a and the thickness of the lower flange 4b of the lower casing 1b are the same (see FIG. 2), but flange bolts are used as in the third embodiment. The central axis of the flange bolt 5 can be brought close to the inner surface side of the casing 1 by increasing only the thickness of the upper flange 4a provided with the through-hole 4a1 through which 5 is inserted.

  In the first embodiment, the upper flange 4a is welded by a welding surface 102b (see FIG. 2) perpendicular to the mating surface 103, but the plate thickness of the plate material that cuts out the upper flange 4a is sufficient with respect to the outer diameter of the nut 5b. In the case of being large, a welding surface 102c inclined with respect to the mating surface 103 is formed on the flange material 109 cut out from the plate material as shown by a two-dot chain line in FIG. It is also possible to cut off unnecessary portions by machining the inner diameter. In the third embodiment, since welding is performed on the welding surface 102c inclined with respect to the mating surface 103, welding is performed on the welding surface 102a (see FIG. 2) perpendicular to the mating surface 103 as in the first embodiment. However, there is an advantage that the welding amount can be reduced. On the other hand, since 1st Embodiment can use what was cut out from the board | plate material as it is as the upper flange 4a as it is, there exists an advantage which can ensure the seat surface of the nut 5b more widely.

  Also according to the third embodiment, it is possible to achieve the same operational effects as those of the first embodiment. In FIG. 6, the through-hole 4a1 is provided in the upper flange 4a and the seat surface of the nut 5b is seated. However, the nut 5b is seated in the lower flange 4b and the screw hole is provided in the upper flange 4a to reverse the upper and lower flanges. In the case of the configuration described above, only the lower flange 4b may be configured to be welded to the body plate portion 6b and the side plate portion 7b at the welding surface 102c inclined with respect to the mating surface 103 of the flange 4. Further, both the upper flange 4a and the lower flange 4b are configured to be welded to the body plate portions 6a and 6b and the side plate portions 7a and 7b, respectively, at the welding surface 102c inclined with respect to the mating surface 103 of the flange 4. Also good.

[Fourth Embodiment]
Next, with reference to FIG. 7, the fourth embodiment of the present invention will be described with a focus on differences from the first embodiment described above, and description of common points will be omitted as appropriate. FIG. 7 is an enlarged perspective view of the vicinity of the top of the side plate portion of the casing according to the fourth embodiment of the present invention.

  As shown in FIG. 7, in the fourth embodiment, the dimension of the upper flange 4a in the direction perpendicular to the mating surface 103 of the portion welded to the side plate portion 7a is the top portion provided on the top portion of the side plate portion 7a. The part close to the through hole 11 is made larger than the other part. Of the upper flange 4a, the portion welded to the side plate portion 7a can be divided into a plurality of linear portions 105 to 107 along the curve of the open end of the side plate portion 7a, so that the thickness of the upper flange 4a can be reduced. It is easy to change by site. Here, the thickness of the linear part 107 which adjoins the top part through-hole 11 among the upper flanges 4a is larger than another part.

  Since the top part of the curved side plate parts 7a and 7b is provided with a top through hole 11 into which a bearing 12 (see FIG. 1) and a shaft seal device are inserted and attached, both sides of the top through hole 11 in the horizontal direction. The load applied to the flange bolt 115 is increased, and the mouth opening is likely to occur at that portion. Therefore, it is effective to make the flange bolts 115 on both sides of the top through-hole 11 closer to the inner surface of the casing 1 than the other flange bolts 5. As described above, the flange bolt 115 can be brought closer to the inner surface of the casing 1 as the thickness of the upper flange 4a is increased. Therefore, in the fourth embodiment, as shown in FIG. 7, the thickness T1 of the upper flange 4a in the vicinity of the top through-hole 11 is made larger than the thickness of other portions. In FIG. 7, the thickness of the upper flange 4 a is increased only in the flange bolt 115 provided on each side of the top through-hole 11. However, the thickness is not limited to this, and the top through-hole is not limited thereto. The thickness of the upper flange 4a of the flange bolt 115 provided on each of the both sides of the flange bolt 115 may be increased.

According to such 4th Embodiment, it becomes possible to suppress more the opening of the mating surface 103 of the flange 4 especially in the vicinity of the top part of the side-plate parts 7a and 7b.
When the nut is seated on the lower flange 4b and the screw hole is provided on the upper flange 4a so that the upper and lower flanges are reversed, the thickness of the portion of the lower flange 4b adjacent to the top through hole 11 is different. It may be set larger than the portion. Further, in both the upper flange 4a and the lower flange 4b, the thickness of the portion adjacent to the top through hole 11 may be set larger than the other portions.
Furthermore, the thickness of the portion welded to the side plate portions 7a and 7b of the flange 4 is not limited to the portion close to the top through hole 11 as shown in FIG. It may be changed so as to gradually increase toward the through hole 11.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to above-described embodiment, Various modifications are included. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. In addition, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  For example, the mechanism part accommodated in the casing 1 may constitute a compressor, or may constitute another turbo machine. That is, the casing 1 can be used as a casing for a turbo machine or a compressor. When the casing 1 is provided in the compressor, an impeller (not shown) is provided as a rotating member, and the bearing 12 supports the rotating shaft of the impeller. When the casing 1 is provided in another turbo machine, a rotating member for realizing each function (for example, an impeller when the turbo machine is a blower) is provided, and the bearing 12 supports the rotating shaft of the rotation. To do.

  Further, the present invention is not limited to the casing 1 divided at the center in the vertical direction, and the present invention can also be applied to the casing 1 divided above or below the center. Moreover, it is also possible to apply this invention to the casing 1 divided | segmented by the horizontal direction orthogonal to an up-down direction. Moreover, although the shape of the casing 1 is substantially cylindrical, this shape is not limited. For example, the present invention can be applied to a casing 1 having a flat shape in which a cylindrical shape is crushed in the vertical direction or the horizontal direction.

1 casing 1a upper casing (first casing)
1b Lower casing (second casing)
3 Nozzle 4 Flange 4a Upper flange (first flange)
4b Lower flange (second flange)
4a1 Through hole 4b1 Screw hole 5 Flange bolt (fastening member)
5a Stud bolt 5b Nut 6 Body plate 6a, 6b Body plate 7 Side plate 7a, 7b Side plate 11 Top through hole (mounting part)
12 Bearing 101a, 101b Welding surface 102a, 102b Welding surface 102c Welding surface 103 Joint surface 104-107 Straight line portion 108 Joint portion 109 Flange material 115 Flange bolt CL Axis line F Force to open the mating surface L From casing inner surface to bolt center axis Distance R Inner radius of casing r Outer radius of nut t Thickness of casing T, T1 Flange thickness W Flange width

Claims (7)

A first casing and a second casing that can be divided by a mating surface formed on a plane including an axis;
The first casing and the second casing are:
A body plate that curves around the axis;
Each having a side plate portion that bulges in a curved shape so that the position on the axis line is the top from the end in the axial direction of the body plate portion,
A mounting portion for attaching a bearing that supports a built-in rotating shaft is provided on the top portion of the side plate portion,
The first casing includes a first flange that is welded to a body plate portion and a side plate portion of the first casing to form the mating surface, and the second casing includes a body plate portion and a side plate portion of the second casing. A second flange that is welded to form the mating surface;
The first flange and the second flange are brought into surface contact with each other at the mating surface and fastened and fixed by a plurality of fastening members,
A welding surface of the first flange welded to the body plate portion and the side plate portion of the first casing, and a welding surface of the second flange welded to the body plate portion and the side plate portion of the second casing. And at least one of them is perpendicular or inclined to the mating surface.   Of the first flange and the second flange, a portion welded to the side plate portion with a welding surface perpendicular or inclined with respect to the mating surface is formed of a plurality of straight portions. The casing according to claim 1.   Of the first flange and the second flange, the dimension of the portion that is welded to the side plate portion by a welding surface that is perpendicular or inclined with respect to the mating surface is close to the top portion. The casing according to claim 1, wherein a portion to be processed is larger than other portions.   Of the first flange and the second flange, a dimension in a direction perpendicular to the mating surface of a portion welded to the side plate portion by a welding surface perpendicular to or inclined with respect to the mating surface is directed toward the top. The casing according to claim 1, wherein the casing is changed to be larger.   A turbomachine comprising the casing according to any one of claims 1 to 4.   A compressor comprising the casing according to any one of claims 1 to 4. It is a manufacturing method of the casing given in any 1 paragraph of Claims 1-4,
One of the first flange and the second flange that is welded at a welding surface that is perpendicular or inclined with respect to the mating surface is formed by cutting a flat plate material,
A method for manufacturing a casing, wherein a surface perpendicular or inclined with respect to the plate thickness direction of the plate material is used as the welding surface, and a surface parallel to the plate thickness direction of the plate material is used as the mating surface.

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