JP2005081432A - Valve housing manufacturing method, and valve manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve housing manufacturing method capable of considerably reducing the constraints of the shape and the dimension of a valve housing to be finally obtained to the shape and the dimension of a tubular member, and preventing generation of any locally thin-walled portion or brittle portion in the valve housing obtained by deforming the shape of the tubular member. <P>SOLUTION: The valve housing manufacturing method comprises a tubular wall expanding step of outwardly expanding a part of a tubular wall by applying the internal pressure to a tubular member 100, and a tubular wall forming step of forming an inner rib 103A by deforming the tubular wall portion on one side in a range of expanding deformation while performing the pattern forming with the internal pressure applied to a tubular member 102, and flattening the tubular wall portion on the other side facing the tubular wall on one side to constitute a flat portion 103B. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a valve housing and a method for manufacturing a valve, and more particularly, to a manufacturing technique suitable for manufacturing a valve housing constituting a diaphragm valve.

  In general, a conventional diaphragm valve is configured by connecting a valve body, a valve driving unit, and the like to a valve housing cast using a metal material. However, valve housings formed by casting methods are subject to structural defects such as carbide precipitation, blowhole formation, and inclusions, and therefore are prone to corrosion and cracking. It is difficult to make it easy to cause fluid contamination.

  Therefore, attempts have been made to perform the valve housing by a forging method. For example, an opening is formed in the tube wall of the tube member, a mold material is introduced into the tube member, and the mold material is drawn out from the opening to form the opening portion, while the tube wall portion facing the opening portion is formed. A method of forming an internal rib protruding toward the opening by applying another mold from the outside to deform the tube wall portion inward and applying another mold from the opening is also known. (For example, refer to Patent Document 1 below).

In addition, a material such as sand is accommodated in the inside of the pipe member, and the pipe member is molded while applying internal pressure, thereby deforming the pipe wall portion on one side of the pipe member to form an internal rib. In addition, a method is also known in which a flat portion is formed by projecting the tube wall portion on the other side (see, for example, Patent Document 2 below).
U.S. Pat. No. 3,300,904 Japanese National Patent Publication No. 10-501466

  However, in the valve housing manufacturing method using the forging method described above, the shape and dimensions of the valve housing finally obtained are largely limited by the diameter of the original pipe member and the thickness of the pipe wall. There is a problem that the degree of freedom becomes low.

  Further, in the case of configuring a diaphragm valve or the like, there is a problem in that the pipe wall needs to be partially largely deformed, so that the pipe wall is locally thinned or the strength is lowered.

  Therefore, the present invention solves the above-mentioned problems, and its problem is to manufacture a valve housing capable of greatly reducing restrictions on the shape and size of the valve housing finally obtained with respect to the shape and size of the pipe member. It is to provide a method. It is another object of the present invention to provide a method for manufacturing a valve housing that does not cause local thin portions or fragile portions in a valve housing obtained by changing the shape of a pipe member.

  In order to solve the above problems, the valve housing manufacturing method of the present invention includes a tube wall expanding step of applying an internal pressure to the tube member to expand a part of the tube wall outward, and then applying the internal pressure to the tube member. By molding in the added state, the tube wall portion on one side in the expansion deformation range is deformed inward to form an internal rib, and the tube wall portion on the other side facing the tube wall on the one side And a tube wall forming step for flattening and forming a flat portion.

  According to this invention, after the tube wall is expanded outward in the tube wall expansion step, the tube wall portion on one side in the expansion deformation range is deformed inward in the tube wall forming step to form the internal rib, Since the tube wall part on the other side is flattened to form a flat part, even if the forming shape and dimensions in the tube wall forming process differ greatly from the original tube member shape and dimensions, it is impossible to deform the tube material. It becomes possible to mold without forcing. Therefore, the restriction of the shape and size of the valve housing with respect to the shape and size of the original pipe member can be reduced, and the valve housing can be molded so as not to cause a locally thin portion or a fragile portion.

  Here, it is desirable that the part of the tube wall expanded outward in the tube wall expansion step is, for example, an intermediate portion (particularly the central portion) in the axial direction of the tube member. As a result, tubular portions (tube end portions to be described later) remain on both sides, so that pipe connection portions can be easily configured at both ends of the valve housing. It is desirable that the expansion deformation range for the pipe member substantially coincides with the range in which the inner rib and the flat portion are deformed in the finally obtained valve housing. In the tube wall forming step, it is desirable to use a hydraulic bulge method in which mold forming is performed in a state where a liquid is supplied in a pressurized state to the inside of the tube member.

  In the present invention, in the tube wall expanding step, it is preferable that the tube wall is formed into a shape expanded outward by performing mold forming with an internal pressure applied to the tube member. According to this, it is possible to easily expand the tube wall to the outside by performing molding while applying the internal pressure, and it is possible to form the expanded tube wall shape with high accuracy. The accuracy of the shape and dimensions of a simple valve housing can be improved. In this tube wall expansion step, it is desirable to use a hydraulic bulge method in which mold forming is performed in a state where a liquid is supplied in a pressurized state to the inside of the tube member.

  In the present invention, the tube wall expanding step is preferably performed while applying an axial compressive force to the tube member. By expanding the tube wall while applying an axial compressive force to the tube member, it is possible to eliminate or suppress a reduction in the wall thickness of the expanded deformation portion of the tube wall. It is possible to prevent the occurrence of a thin portion or a fragile portion. Here, it is desirable that the compressive force in the axial direction of the pipe member is given by a pressurizing action by a seal member that seals both ends of the pipe member in order to apply an internal pressure to the pipe member.

  In this invention, it is preferable that the said pipe wall shaping | molding process is performed in the state which fixed the both ends of the said pipe member. According to this, since the tube wall forming step is performed with both ends of the tube member fixed, both ends of the tube member do not move during forming, so that it is possible to prevent buckling of the bent portion and the like. The reproducibility of the thickness of a typical valve housing can be improved. Here, it is desirable that both ends of the tube member are fixed by seal members that seal the both ends of the tube member in order to apply internal pressure to the tube member. In this case, a taper seal structure that seals in a state where both ends of the tube member are expanded in a tapered shape can be used as a fixing method.

  In this invention, it has the preforming process which preforms so that the expanded tube wall part may become a shape closer to the said inner rib and the said flat part between the said tube wall expansion process and the said tube wall shaping | molding process. It is preferable. According to this, it is possible to prevent wrinkles on the outer surface of the tube wall by preforming the tube wall portion expanded in the tube wall expansion step. Moreover, the followability at the time of shaping | molding can be improved and the moldability of a protrusion part can be improved especially. Here, the preforming can be performed by plastic working such as press working. Also, molding is performed using a molding die that has substantially the same mold shape as the tube wall molding process without applying internal pressure (that is, the inner rib and the main molding part that should be flat have the same mold shape). It is desirable to do.

  In this invention, it is preferable to have an opening formation process which forms an opening in the said flat part. According to this, an opening can be provided at a position opposite to the internal rib configured to protrude into the flow path, and a structure that generates a valve action through this opening can be configured. Here, one or a plurality of openings may be provided in a part of the flat portion, and openings may be provided in the entire flat portion.

  The valve manufacturing method of the present invention is characterized in that the valve is formed by attaching a valve drive unit to the valve housing manufactured by the above-described valve housing manufacturing method. The above valve housing is provided with an internal rib protruding into the flow path, and this internal rib can be used either alone or with the help of other valve structural members. , Configured to be divided. As a valve structure constituted by the present invention, a diaphragm valve is typical, but a seating type valve structure (a partition valve) or the like can also be configured according to the structure of the valve drive unit.

  According to the present invention, restrictions on the shape and size of the valve housing finally obtained with respect to the shape and size of the pipe member can be greatly reduced. Moreover, the valve housing obtained by deforming the shape of the pipe member can have an excellent effect of preventing a locally thin portion or a fragile portion from being generated.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the manufacturing method, valve housing, valve structure, and the like described below are merely examples, and do not limit the technical scope of the present invention.

  First, an embodiment of a method for manufacturing a valve housing according to the present invention will be described. FIG. 1 is an explanatory view showing the cross-sectional shape of a workpiece to be processed by the manufacturing method of this embodiment for each process, and FIGS. 2 to 6 are process explanatory cross-sectional views sequentially showing the processing state in each process.

  In this embodiment, as shown in FIG. 1, a pipe member 100 made of metal is used as a raw material. In the illustrated example, the tube member 100 is a circular cylindrical member having a predetermined length L1 and having an inner diameter and an outer diameter equal to the axial direction. The pipe member 100 is made of an appropriate metal material such as stainless steel, titanium, titanium alloy, or the like. In particular, it is preferably composed of an alloy for forging. Specific examples include SUS316L (JIS standard).

  First, as shown in FIG. 2, a part of the pipe member 100 is expanded and deformed by a hydraulic bulge method (bulge processing) using molding dies 201A and 201B and seal members 201C and 201D made of metal or the like. (Tube wall expansion process). This hydraulic bulge method refers to a method in which an ultra-high pressure liquid is fed into a tubular material, and a part of the material is inflated into a shape as in a molding die for cold forming. As the liquid, various oils, water, aqueous solutions, and the like can be used. The hydraulic pressure depends on the material of the workpiece, but is usually about 10 to 200 [MPa]. As shown in FIG. 3, the seal members 201C and 201D are in contact with both ends of the tube member 100, and in a state where the inside of the tube member 100 is sealed, the liquid 202 is discharged from the liquid passage 201Ca provided in the seal member 201C. Send it in. In this case, the seal members 201 </ b> C and 201 </ b> D are pressed against both ends of the tube member 100 with a pressure equal to or higher than the pressure applied to the liquid 202, thereby ensuring the sealing performance of the tube member 100.

  Thereafter, the pipe member 100 is sandwiched between the molding dies 201A and 201B and is fixed with a sufficient clamping force. Then, the internal pressure of the pipe member 100 is increased by gradually increasing the pressure of the liquid 202. As a result, the tube wall of the tube member 100 is pressed from the inside by the pressure of the liquid 202, and a part of the tube wall expands along the cavity formed by the molds 201A and 201B. Here, a part of the pipe wall to be expanded is set in an intermediate part in the axial direction excluding both ends of the pipe member 100. In particular, it is preferable that the expanded deformation portion is a central portion in the axial direction of the pipe member 100. At this time, the pressing force in the axial direction by the seal members 201C and 201D is configured to be directly applied to the pipe member 100, whereby the pipe member 100 is processed in a state of receiving the compressive force in the axial direction. become.

  In the present embodiment, as shown in FIG. 1, the tube member 101 having the expanded deformation portion 101 </ b> A that defines the expanded deformation range and the tube end portions 101 </ b> B provided on both sides thereof as shown in FIG. Is formed. In the illustrated example, the expanded deformed portion 101A has a spherically bulging shape. The tube end portion 101B is almost the same as the shape of the first tube member 100. Since the tube wall expansion step is performed in a state where the axial compressive force is applied by the seal members 201C and 201D, the length L2 of the tube member 101 is shorter than the length L1 of the tube member 100. This shortening amount ΔL = L1−L2 is preferably set so that the expanded tube wall in the expanded deformation portion 101A does not change with the thickness of the tube wall of the original tube member 100. This setting can be performed by adjusting the internal pressure applied to the tube member 100 by the liquid 202 and the compressive force applied to the tube member 100 by the seal members 201C and 201D.

  In addition, the width L3 in the axial direction of the above-described expanded deformed portion 101A is preferably set so as to substantially coincide with a range in which the tube shape is deformed by molding of internal ribs and flat portions described later. This setting is made according to the cavity shape of the molds 201A and 201B.

  Next, as shown in FIG. 4, the pipe member 101 in which a part of the pipe wall is expanded as described above is plastically processed by molding using molding dies 203A and 203B having movable dies 203a and 203b. (Preliminary molding step). In this pre-forming step, no internal pressure is applied to the tube member 101, and die forming is performed by simple press work or the like.

  Here, as shown in FIG. 5, the movable mold 203a (punch) approaches the tube wall of the expanded deformation portion 101A of the tube member 101 and deforms the expanded deformation portion 101A inward. As a result, a preliminary internal rib 102A having a shape close to an internal rib described later is formed. This preliminary internal rib 102A is constituted by a tube wall portion protruding into the tube member.

  On the other hand, the movable mold 203b is configured to be movable up and down by a spring or the like, and is configured to return to the illustrated position against a pressing force during processing (knockout punch). A preliminary flat portion 102B is formed on the tube wall portion facing the preliminary internal rib 102A by 203b.

  In the molding shown in FIG. 5, the molding dies 203 </ b> A and 203 </ b> B have substantially the same cavity shape as a molding die used in a tube wall molding process to be performed later. That is, at least the cavity portion (the surface of the movable mold 203a) for forming the preliminary internal rib 102A is the same as the cavity portion for molding the internal rib used in the tube wall molding process described later, and the preliminary flat portion 102B is molded. The cavity portion (the portion defined by the surface position of the movable die 203b in the molding die 203B) is the same as the cavity portion for molding the flat portion used in the tube wall molding process described later.

  The tube member 102 formed as described above is formed by forming the preliminary internal rib 102A and the preliminary flat portion 102B in the axial direction intermediate portion (center portion) by the preliminary forming step. The tube end portion 102C basically has the same shape as the tube members 100 and 101.

  Finally, a tubular member 103 having a final forged shape as a valve housing is obtained by a hydraulic bulge method (bulge process) using the molds 204A and 204B and the sealing materials 204C and 204D shown in FIG. Wall forming process). This hydraulic bulge method is the same method as that described in the tube wall expansion step. In this step, the internal rib 103A and the flat portion 103B are formed by the internal pressure applied by the liquid. The internal rib 103A is formed by deforming the tube wall portion on one side inward and projecting it inside. Further, the flat portion 103B is formed by deforming the tube wall portion on the other side facing the internal rib 103A and forming a flat surface portion at a position protruding slightly outward.

  The molds 204A and 204B have the same cavity structure as that in the preliminary molding step, and the movable mold 204b provided in the mold 204B has the same structure (knockout punch structure) as the movable mold 203b. Is.

  In this process, both end edges of the tube end portion 103C are sandwiched between the molds 204A and 204B and the sealing materials 204C and 204D, and the both ends are sealed in a state of being tapered so as to open outward in the axial direction. Hold. By adopting such a taper seal structure, the sealing structure can be maintained during processing, and both end portions of the tube member can be fixed in the axial direction. Therefore, by increasing the pressure of the liquid to increase the internal pressure, when the tube wall of the tube member is formed into a shape along the cavity inner surface of the forming molds 204A and 204B, both ends of the tube member are displaced. Can be prevented. For example, both ends of the pipe member can be prevented from being drawn inward during processing. Therefore, there is an advantage that the shape of the finally obtained valve housing can be formed with high reproducibility and high accuracy.

  As described above, as shown in FIG. 1, the tube member 103 including the internal rib 103A, the flat portion 103B, and the tube end portion 103C is formed. The internal flow path 103P is incompletely divided by the internal rib 103A. Here, in the tube member 103, the axial range L4 deformed by providing the internal rib 103A and the flat portion 103B is the axial range L3 of the expanded deformed portion 101A expanded in the tube wall expanding step. It is set to be the same length. As a result, the inner rib 103A and the flat portion 103B can be formed without excessive deformation, so that the thickness of the tube wall of these portions can be kept uniform.

  The tube member 103 formed as described above has a diameter-expanded taper portion 103d formed by the taper seal structure at the end edge of the tube end portion 103C. The diameter-expanded taper portion 103d is separated from the tube end portion 103C by cutting or the like. In addition, an appropriate opening is formed in the flat portion 103B. For example, by dividing the flat portion 103B by a plane parallel to the axial direction by cutting or the like, the entire flat portion 103B has an open shape. In this way, the valve housing 110 shown in FIGS. 7 to 11 is completed.

  As shown in FIGS. 7 to 11, the valve housing 110 has an opening 110 </ b> Q that opens inside an opening edge 110 b that is flat, and an internal rib 110 </ b> A projects into the opening 110 </ b> Q. ing. FIG.10 (b) shows the end surface cut | disconnected along the Xb-Xb line | wire of FIG. Here, the dashed-dotted line in the figure indicates a portion where the flat portion 103B of the tube member 103 is cut. As shown in FIG. 10B, the tip of the internal rib 110A has a shape that is slightly concavely curved in the width direction. Further, a flow path is formed inside the valve housing 110, and this flow path is incompletely divided by the internal rib 110A. Tubular tube end portions 110C are provided on both sides of the opening 110Q and the internal rib 110A.

  In the present embodiment, by providing the tube wall expansion step, it is possible to ensure a deformation margin of the internal rib 103A and the flat portion 103B, so that the internal rib 103A and the flat portion are formed with respect to the shape and thickness of the pipe member 100. Even if the outer diameter of the region where 103B is formed (the diameter of the flat portion 103B) is set to be significantly large, it is possible to perform reasonable plastic working, and local thin portions and fragile portions are generated in the valve housing 110. Can be prevented. In particular, the tube wall portion 110X that is obliquely enlarged in the width direction of the internal rib 110A from the tube end portion 110C to the formation region of the internal rib 110A shown in FIG. In the conventional method, the tube wall portion 110X is cracked or cannot be processed into the designed shape. In the present embodiment, since the molding is performed after the tube wall is expanded as described above, the tube wall portion 110X is not cracked, and the thickness is as designed. can do.

  In the present embodiment, in the tube wall expansion step, the tube member 100 is molded with an axial compressive force applied thereto, so that a desired expansion shape can be obtained while suppressing a decrease in the wall thickness of the tube wall. it can. Further, by using the hydraulic bulge method, the expanded shape can be formed with high accuracy, and the occurrence of distortion and the like due to deformation for expansion can be reduced.

  In addition, by providing a preforming step between the tube wall expanding step and the tube wall forming step, it is possible to prevent generation of wrinkles on the outer surface of the valve housing due to abrupt deformation. The shape of the protruding portion such as the curved shape of the tip portion and the curved shape of the peripheral portion of the flat portion 103B can be formed more smoothly and with good reproducibility.

  Furthermore, since the tube wall forming step is performed by a hydraulic bulge method, the shape of the tip of the internal rib 103A can be formed with high reproducibility and high accuracy. As a result, the performance of the valve can be improved particularly when a diaphragm valve is configured. In this tube wall forming process, since the tube member is formed in a state where both ends are fixed, the tube member is not pulled in at the time of forming. Therefore, it is possible to prevent problems such as buckling of a bent portion (for example, the peripheral portion of the flat portion 103B), and it is possible to further improve molding reproducibility and shape accuracy.

  FIG. 12 shows a structure of a diaphragm valve 200 using the valve housing 110 described above. The diaphragm valve 200 includes a valve driving unit 210, and the valve driving unit 210 is connected to the valve housing 110. The valve drive unit 210 includes a casing 211, a drive member 212 configured to be movable in the vertical direction in the figure, and a diaphragm 213 that is deformed up and down by the drive member 212. Here, the drive member 212 is connected to a drive motor, a fluid pressure cylinder, a rotary handle, a rotary lever, etc. (not shown). The valve driving part 210 and the valve housing 110 are sealed by a sealing material 214 disposed around the opening edge part 110b. The diaphragm 213 is disposed in the opening 110Q and is configured to be deformed by being driven by the driving member 212. By the deformation, the flow path 110P can be closed by being in close contact with the internal rib 110A. The flow path 110P can be opened by separating from the internal rib 110A.

  FIG. 13 shows a valve housing 110 ′ having a structure different from the above. The valve housing 110 ′ has an internal rib 110A ′ and a pipe end portion 110C ′ similar to the valve housing 110, but an opening 110Q smaller than the flat portion 110B is formed in the central portion of the flat portion 110B. It differs from the valve housing 110 'in that it is formed so as to face. The valve housing 110 ′ can be used, for example, for a gate valve having a valve body configured to be movable up and down through the opening 110Q ′.

  FIG. 14 shows a valve housing 110 ″ having still another structure. The valve housing 110 ″ has an internal rib 110A ″ that abuts against the flat portion 110B ″ from the inside to completely cut off the internal flow path. In that it differs from the valve housing. The flat portion 110B ″ is formed with openings 110Q and 110R that open to the flow path portions separated by the internal ribs 110A ″.

  The valve housing 110 ″ has a valve passage (not shown) extending from a connection port connected to the opening 110Q to a connection port connected to the opening 110R, and is opened and closed by a valve body (not shown). It can be used together with various configured valve drive units, and the valve body configuration configured inside the valve drive unit in this case can adopt any configuration such as a diaphragm valve, a gate valve, and a ball valve.

Sectional drawing which shows the change of the shape of the workpiece in embodiment of the manufacturing method of a valve housing. Sectional drawing which shows the type | mold structure used for the pipe wall expansion process of the embodiment. Sectional drawing which shows the mode of the pipe wall expansion process of the embodiment. Sectional drawing which shows the type | mold structure used for the preforming process of the embodiment. Sectional drawing which shows the mode of the preforming process of the embodiment. Sectional drawing which shows the mode of the pipe wall shaping | molding process of the embodiment. The top view of a valve housing. The bottom view of a valve housing. The front view of a valve housing. The side view (a) of a valve housing, and the end view (b) of the formation part of an internal rib. The perspective view of a valve housing. The partial cross section figure of a diaphragm valve. FIG. 6 is a cross-sectional view of another valve housing. Sectional drawing of another valve housing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100,101,102,103 ... Pipe member, 101A ... Expansion deformation part, 103A ... Internal rib, 103B ... Flat part, 103C ... Pipe end part, 110 ... Valve housing, 110A ... Internal rib, 110b ... Opening edge part, 110Q ... Opening part, 110C ... Pipe end part, 200 ... Diaphragm valve

Claims (7)

  A tube wall expanding step in which an internal pressure is applied to the tube member to expand a part of the tube wall outward, and thereafter, molding is performed with the internal pressure applied to the tube member, whereby one side of the tube within the expansion deformation range is formed. And a tube wall forming step of forming a flat portion by deforming the wall portion inward to form an internal rib and flattening the tube wall portion on the other side facing the tube wall on the one side. A method for manufacturing a valve housing.   2. The valve housing according to claim 1, wherein, in the tube wall expanding step, the tube wall is formed into a shape expanded outward by performing mold forming with an internal pressure applied to the tube member. Production method.   The method of manufacturing a valve housing according to claim 1 or 2, wherein the tube wall expansion step is performed while applying an axial compressive force to the tube member.   The method for manufacturing a valve housing according to any one of claims 1 to 3, wherein the tube wall forming step is performed in a state where both ends of the tube member are fixed.   Between the tube wall expanding step and the tube wall forming step, there is a preforming step in which the expanded tube wall portion is preformed so as to be closer to the inner rib and the flat portion. The manufacturing method of the valve housing as described in any one of Claim 1 thru | or 4.   The method for manufacturing a valve housing according to claim 1, further comprising an opening forming step of forming an opening in the flat portion. A method for manufacturing a valve, comprising: forming a valve by attaching a valve drive unit to the valve housing manufactured by the method for manufacturing a valve housing according to claim 6.

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