Patent Publication Number: US-2023160050-A1

Title: Treatment device, treatment method, method for manufacturing metal pipe material, and metal pipe material

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a bypass continuation of International PCT Patent Application No. PCT/JP2021/030646, filed on Aug. 20, 2021, which claims priority to Japanese Patent Application No. 2020-148328, filed on Sep. 3, 2020, which are incorporated by reference herein in their entirety. 
    
    
     BACKGROUND 
     Technical Field 
     A certain embodiment of the present invention relates to a treatment device, a treatment method, a method for manufacturing a metal pipe material, and a metal pipe material. 
     Description of Related Art 
     In the related art, there is known a treatment device that performs treatment for forming a plating layer on a metal pipe material that is used as a material for hot forming. In this treatment device, a plating material is supplied to a welded portion of the metal pipe material from the outer periphery side (Al thermal spraying). Accordingly, in the treatment device, it is not possible to cover the outer periphery-side surface of the welded portion with a plating layer. 
     SUMMARY 
     According to an aspect of the present invention, there is provided a treatment device that performs treatment for forming a plating layer on a metal pipe material that is used as a material for hot forming, the treatment device including a supply unit that supplies a plating material to an inner periphery-side surface of a welded portion formed in the metal pipe material. 
     According to another aspect of the present invention, there is provided a treatment method for performing treatment for forming a plating layer on a metal pipe material that is used as a material for hot forming, the treatment method including a process of supplying a plating material to an inner periphery-side surface of a welded portion formed in the metal pipe material. 
     According to still another aspect of the present invention, there is provided a metal pipe material manufacturing method for manufacturing a metal pipe material from a plate material with a plating layer formed thereon, the method including performing, after end portions of the plate material are joined together by welding, plating treatment on a location where the plating layer has been peeled off due to the welding, of an inner peripheral surface of the metal pipe material. 
     According to still another aspect of the present invention, there is provided a metal pipe material that is used as a material for hot forming, and in which an inner periphery-side surface of a welded portion is covered with a plating layer. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic configuration diagram showing a schematic configuration of a metal pipe material manufacturing apparatus in which a treatment device according to an embodiment of the present invention is adopted. 
         FIG.  2 A  is a schematic sectional view showing a state of a treatment device in a state of being disposed inside a metal pipe material,  FIG.  2 B  is a sectional view taken along line IIb-IIb of  FIG.  2 A , and  FIG.  2 C  is a sectional view taken along line IIc-IIc of  FIG.  2 A . 
         FIG.  3 A  is a schematic sectional view showing a state of a treatment device according to a modification example in a state of being disposed inside a metal pipe material,  FIG.  3 B  is a sectional view taken along line IIIb-IIIb of  FIG.  3 A , and  FIG.  3 C  is a sectional view taken along line IIIc-IIIc of  FIG.  3 A . 
         FIG.  4    is a schematic sectional view showing a state of a treatment device according to a modification example in a state of being disposed inside a metal pipe material. 
         FIG.  5 A  is a sectional view taken along line Va-Va of  FIG.  4   ,  FIG.  5 B  is a sectional view taken along line Vb-Vb of  FIG.  4   ,  FIG.  5 C  is a sectional view taken along line Vc-Vc of  FIG.  4   , and  FIG.  5 D  is a sectional view taken along line Vd-Vd of  FIG.  4   . 
         FIG.  6    is a perspective view of a metal pipe material according to an embodiment of the present invention. 
         FIG.  7 A  is a diagram showing a metal pipe material as viewed from an axial direction,  FIG.  7 B  is an enlarged diagram showing the state of the vicinity of a welded portion in a step before forming a plating layer, and  FIG.  7 C  is an enlarged diagram showing the state of the vicinity of the welded portion in a state where the plating layer has been formed. 
         FIG.  8    is a schematic sectional view showing a state of a treatment device according to a modification example in a state of being disposed inside a metal pipe material. 
         FIG.  9    is a schematic sectional view showing a state of a treatment device according to a modification example in a state of being disposed inside a metal pipe material. 
         FIG.  10    is a schematic sectional view showing a state of a treatment device according to a modification example in a state of being disposed inside a metal pipe material. 
     
    
    
     DETAILED DESCRIPTION 
     A treatment device such as that of the related art described above can cover the surface of the welded portion with a plating layer from the outer periphery side. However, it is not possible to form a plating layer on the inner periphery-side surface of the welded portion. Accordingly, the inner periphery-side surface of the welded portion is exposed, so that there is a possibility that oxide scale may be generated on the surface. 
     It is desirable to provide a treatment device, a treatment method, a method for manufacturing a metal pipe material, and a metal pipe material, in which it is possible to manufacture a metal pipe material in which the generation of oxide scale can be suppressed. 
     The treatment device includes the supply unit that supplies the plating material to the inner periphery-side surface of the welded portion formed in the metal pipe material. In this way, the inner periphery-side surface of the welded portion of the metal pipe material is covered with the plating layer formed of the plating material. In this way, the welded portion can be prevented from being exposed on the inner periphery side of the metal pipe material. With the above, it is possible to manufacture the metal pipe material in which the generation of oxide scale can be suppressed. 
     The treatment device may further include a cutting unit provided on an upstream side of a location to which the plating material is supplied by the supply unit, in a feed direction of the metal pipe material, to cut the welded portion from an inner periphery side of the metal pipe material. In this case, after an excess portion on the inner periphery side of the welded portion is removed by the cutting unit, the supply unit can immediately form a plating layer on the inner periphery-side surface of the welded portion. 
     According to this treatment method, the same operation and effect as those of the treatment device described above can be obtained. 
     According to the method for manufacturing a metal pipe material, even in a case where the plating layer is peeled off due to joining the end portions of the plate material together by welding, the peeled location can be covered with the plating layer again by performing plating treatment on the peeled location. With the above, it is possible to manufacture the metal pipe material in which the generation of oxide scale can be suppressed. 
     According to this metal pipe material, the same operation and effect as those of the treatment device described above can be obtained. 
     Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. In each drawing, identical or corresponding portions are denoted by the same reference numerals, and overlapping description is omitted. 
       FIG.  1    is a schematic configuration diagram showing a schematic configuration of a metal pipe material manufacturing apparatus  100  in which a treatment device  50  according to an embodiment of the present invention is adopted. The metal pipe material manufacturing apparatus  100  is an apparatus for manufacturing a metal pipe material that is used as a material for hot forming. As the hot forming that is used for a metal pipe material, for example, expansion forming can be given in which forming and quenching are simultaneously performed by placing a heated metal pipe material in a die and expanding it. In addition, hot forming such as induction quenching, hot bending forming, and hot drawing can be given. 
     Here, a metal pipe material  20  will be described with reference to  FIG.  6    and  FIGS.  7 A to  7 C .  FIG.  6    is a perspective view of the metal pipe material  20  according to the present embodiment.  FIGS.  7 A to  7 C  are schematic diagrams for describing the states of a plating layer formed on the metal pipe material  20 . As shown in  FIG.  6   , the metal pipe material  20  has a welded portion  15  called a weld bead or the like, in which end portions  14   a  and  14   a  of a plate material  14  are welded together. More specifically, the metal pipe material  20  is formed by rounding a flat plate-shaped metal plate material  14  into a cylindrical shape and welding the opposite end portions  14   a  and  14   a  together in a state of being abutted against each other. The welded portion  15  in which the metal pipe material  20  is welded in this manner extends along a central axis L of the metal pipe material  20 . The central axis L of the metal pipe material  20  is parallel to an extending direction D of the metal pipe material  20 . 
       FIG.  7 A  is a diagram showing the metal pipe material  20  as viewed from an axial direction.  FIG.  7 B  is an enlarged diagram showing the state of the vicinity of the welded portion  15  in a step before forming a plating layer.  FIG.  7 C  is an enlarged diagram showing the state of the vicinity of the welded portion  15  in a state where the plating layer has been formed.  FIGS.  7 B and  7 C  are enlarged diagrams of an area surrounded by a dashed line circle in  FIG.  7 A . As shown in  FIGS.  7 B and  7 C , a plating layer  16  is formed on the outer peripheral surface of the metal pipe material  20  so as to cover the entire outer peripheral surface. Further, a plating layer  17  is formed on the inner peripheral surface of the metal pipe material  20  so as to cover the entire inner peripheral surface. The plating layers  16  and  17  are originally formed on both surfaces of the plate material  14  in a step before the plate material  14  is rounded into a cylindrical shape. The plating layers  16  and  17  are formed by performing, for example, AlSi plating treatment on the plate material  14 , which is a steel sheet. 
     As shown in  FIG.  7 B , immediately after the welded portion  15  is formed, a state is created where the plating layers  16  and  17  that have been originally present are peeled off at the location of the welded portion  15 . That is, the location of the welded portion  15 , of the outer peripheral surface of the metal pipe material  20 , is a location where the plating layer  16  is peeled off due to welding. At this location, an outer periphery-side surface  15   a  of the welded portion  15  is exposed. The location of the welded portion  15 , of the inner peripheral surface of the metal pipe material  20 , is a location where the plating layer  17  is peeled off due to welding. At this location, an inner periphery-side surface  15   b  of the welded portion  15  is exposed. 
     On the other hand, in the metal pipe material  20  pertaining to a finished product, as shown in  FIG.  7 C , the outer periphery-side surface  15   a  of the welded portion  15  is covered with a plating layer  18 . The inner periphery-side surface  15   b  of the welded portion  15  is covered with a plating layer  19 . The plating layers  18  and  19  are formed to extend along the longitudinal direction of the metal pipe material  20  so as to fill the gaps of the plating layers  16  and  17 . The plating layer  18  on the outer periphery side is formed by performing Al thermal spraying on the surface  15   a  of the welded portion  15  from the outer periphery side of the metal pipe material  20 . The plating layer  19  on the inner periphery side is formed by the plating treatment using the treatment device  50  which will be described later. 
     It returns to  FIG.  1   , and the metal pipe material manufacturing apparatus  100  is described. As shown in  FIG.  1   , the metal pipe material manufacturing apparatus  100  includes a plate material supply device  1 , a forming device  2 , a welding device  3 , the treatment device  50 , and a cutting device  4 . The plate material supply device  1  is a device for supplying the plate material  14  (refer to  FIG.  6    and  FIGS.  7 A to  7 C ), which is a precursor of the metal pipe material  20 . The plate material supply device  1  supplies the plate material  14  in a flat plate state to the forming device  2 . The plate material supply device  1  supplies the plate material  14  by rotating a roll body formed by winding a belt-shaped plate material  14  into a roll shape. The forming device  2  is a device for forming the plate material  14  into a cylindrical shape. The forming device  2  rounds the flat belt-shaped plate material  14  to form it in a cylindrical shape such that the end portions  14   a  and  14   a  in the width direction of the belt-shaped plate material  14  are abutted against each other. 
     The welding device  3  is a device that welds the abutting portions of the end portions  14   a  and  14   a  of the rounded plate material  14  to each other. In this way, the welded portion  15  is formed along the longitudinal direction. The welding device  3  forms the welded portion  15  by, for example, irradiating a welded location with a high frequency or the like. There is a case where the welded portion  15  immediately after welding swells in the thickness direction from the inner peripheral surface or the outer peripheral surface of the metal pipe material  20  (for example, refer to  FIG.  4    (described later)). Therefore, the welding device  3  includes a cutting mechanism for cutting the swelled portion of the welded portion  15  immediately after welding. 
     The treatment device  50  is a device that forms the plating layers  18  and  19  by performing plating treatment on the location of the welded portion  15 . The treatment device  50  includes a mechanism for forming the plating layer  18  on the outer periphery side, and a mechanism for forming the plating layer  19  on the inner periphery side. Details of the mechanism for forming the plating layer  19  on the inner periphery side will be described later. The cutting device  4  is a device for cutting the metal pipe material  20  to a desired length. By cutting with the cutting device  4 , the metal pipe material  20  as shown in  FIG.  6    is completed. 
     Next, a specific configuration of the treatment device  50  will be described with reference to  FIGS.  2 A to  2 C .  FIG.  2 A  is a schematic sectional view showing a state of the treatment device  50  in a state of being disposed inside the metal pipe material  20 .  FIG.  2 B  is a sectional view taken along line IIb-IIb of  FIG.  2 A .  FIG.  2 C  is a sectional view taken along line IIc-IIc of  FIG.  2 A .  FIGS.  2 A to  2 C  show an inner periphery-side plating layer forming mechanism  51  for forming the plating layer  19  on the inner periphery side, of the treatment device  50 . A mechanism for forming the plating layer  18  on the outer periphery side, of the treatment device  50 , is omitted. In  FIGS.  2 A to  2 C , the plating layer  19  is shown to be thicker than the other plating layers in a deformed state. 
     As shown in  FIG.  2 A , the inner periphery-side plating layer forming mechanism  51  of the treatment device  50  includes a rod  52 , a roller  53 , and a supply unit  54 . The plating layer forming mechanism  51  is disposed in an internal space SP on the inner periphery side of the metal pipe material  20 . The metal pipe material  20  is disposed such that the longitudinal direction thereof is parallel to the horizontal direction. Further, the metal pipe material  20  is sent in a feed direction D 1  in a state where the welded portion  15  is disposed on the upper end side. Here, the plating layer forming mechanism  51  is fixed so as not to move in the internal space of the metal pipe material  20 . Therefore, the metal pipe material  20  moves toward the feed direction D 1 , so that the metal pipe material  20  moves relative to the plating layer formation mechanism  51 . 
     As shown in  FIGS.  2 A and  2 B , the rod  52  is disposed parallel to the longitudinal direction of the metal pipe material  20  within the internal space SP of the metal pipe material  20 . The rod  52  is disposed on the lower end side of the internal space SP and disposed on the inner peripheral surface of the lower end portion of the metal pipe material  20  through the roller  53 . In this way, when the metal pipe material  20  is sent in the feed direction D 1 , the roller  53  rotates while guiding the metal pipe material  20  in the feed direction D 1 . The rod  52  is configured with a cylindrical member. 
     As shown in  FIG.  2 A , the supply unit  54  supplies a plating material  58  for forming the plating layer  19  to the inner periphery-side surface  15   b  of the welded portion  15  formed in the metal pipe material  20 . In the present embodiment, the supply unit  54  supplies Al paint as the plating material  58 . Specifically, the supply unit  54  includes a supply pipe  56  that supplies the plating material  58 , and an injection nozzle  57  that injects the plating material  58 . The supply pipe  56  extends parallel to the longitudinal direction of the rod  52  within the rod  52 . The plating material  58  flows toward the injection nozzle  57  side in the supply pipe  56 . The injection nozzle  57  injects the plating material  58  supplied from the supply pipe  56  toward the welded portion  15  on the upper side. The injection nozzle  57  is connected to the supply pipe  56  at the end portion in the longitudinal direction of the rod  52 . The injection nozzle  57  extends so as to be curved upward from the end portion of the supply pipe  56 . In this way, as shown in  FIG.  2 C , the plating material  58  is applied to the inner periphery-side surface  15   b  of the welded portion  15 , and the plating material  58  is dried to form the plating layer  19 . 
     As the plating material  58  that is supplied by the supply unit  54 , for example, paint obtained by mixing fine particles of Al and Si in an organic solvent may be adopted. In this paint, the organic solvent volatilizes in a heating process, and the remaining Al and Si components remain on the surface of an iron base material, so that it is possible to form a plating layer that can suppress the generation of oxide scale, like an AlSi plating material. 
     Next, the operation and effect of the treatment device  50 , a treatment method, a method for manufacturing the metal pipe material  20 , and the metal pipe material  20  according to the present embodiment will be described. 
     The treatment device  50  includes the supply unit  54  that supplies the plating material  58  to the inner periphery-side surface  15   b  of the welded portion  15  formed in the metal pipe material  20 . In this way, the inner periphery-side surface  15   b  of the welded portion  15  of the metal pipe material  20  is covered with the plating layer  19  formed of the plating material  58 . In this way, the welded portion  15  can be prevented from being exposed on the inner periphery side of the metal pipe material  20 . With the above, it is possible to manufacture the metal pipe material  20  in which the generation of oxide scale can be suppressed. 
     The treatment method is a treatment method of performing treatment for forming the plating layer  19  on the metal pipe material  20  that is used as a material for hot forming, the treatment method including a process of supplying the plating material  58  to the inner periphery-side surface  15   b  of the welded portion  15  formed in the metal pipe material  20 . 
     According to this treatment method, the same operation and effect as those of the treatment device  50  device described above can be obtained. 
     The metal pipe material manufacturing method is a method for manufacturing the metal pipe material  20  from the plate material  14  with the plating layer  17  formed thereon, the method including performing, after the end portions  14   a  and  14   a  of the plate material  14  are joined together by welding, plating treatment on a location where the plating layer  17  has been peeled off due to the welding, of the inner peripheral surface of the metal pipe material  20 . 
     According to the method for manufacturing the metal pipe material  20 , even in a case where the plating layer  17  is peeled off due to joining the end portions  14   a  and  14   a  of the plate material  14  together by welding, the peeled location can be covered with the plating layer  19  again by performing plating treatment on the peeled location. With the above, it is possible to manufacture the metal pipe material  20  in which the generation of oxide scale can be suppressed. Further, it is possible to manufacture the metal pipe material  20  having high rust prevention performance. 
     As a method of preventing oxide scales, there is also a method of applying antirust paint to the entire bare metal pipe material  20 . However, in this method, it is difficult to evenly apply a plating material to the inner and outer surfaces, and the cost also increases. In contrast, the treatment device  50  of the present embodiment performs treatment in a manner of repairing a partial location where the plating layer has been peeled off, and therefore, reliability is high, and the number of processes is not increased, so that the degree of increase in cost can also be kept small. 
     The metal pipe material  20  is the metal pipe material  20  that is used as a material for hot forming, and in which the inner periphery-side surface  15   b  of the welded portion  15  is covered with the plating layer  19 . 
     According to the metal pipe material  20 , the same operation and effect as those of the treatment device  50  device described above can be obtained. 
     The present invention is not limited to the embodiment described above. 
     For example, the direction in which the injection nozzle  57  of the supply unit  54  supplies the plating material  58  is not particularly limited, and the treatment device  50  as shown in  FIGS.  3 A to  3 C  may be adopted.  FIG.  3 A  is a schematic sectional view showing a state of the treatment device  50  according to a modification example in a state of being disposed inside the metal pipe material  20 .  FIG.  3 B  is a sectional view taken along line IIIb-IIIb of  FIG.  3 A .  FIG.  3 C  is a sectional view taken along line IIIc-IIIc of  FIG.  3 A . In the treatment device  50  as shown in  FIGS.  3 A to  3 C , the injection nozzle  57  supplies the plating material  58  downward. Accordingly, the welded portion  15  of the metal pipe material  20  is also disposed on the lower end side of the metal pipe material  20 . As shown in  FIG.  3 B , a pair of rollers  53  are provided with the welded portion  15  interposed therebetween when viewed in the axial direction on the lower end side of the rod  52  such that the rollers  53  and the welded portion  15  do not interfere with each other. 
     Further, the treatment device  50  as shown in  FIG.  4    and  FIGS.  5 A to  5 D  may be adopted.  FIG.  4    is a schematic sectional view showing a state of the treatment device  50  according to a modification example in a state of being disposed inside the metal pipe material  20 .  FIG.  5 A  is a sectional view taken along line Va-Va of  FIG.  4   .  FIG.  5 B  is a sectional view taken along line Vb-Vb of  FIG.  4   .  FIG.  5 C  is a sectional view taken along line Vc-Vc of  FIG.  4   .  FIG.  5 D  is a sectional view taken along line Vd-Vd of  FIG.  4   . 
     As shown in  FIG.  4   , the treatment device  50  further includes a cutting unit  59  that is provided on the upstream side of the location to which the plating material  58  is supplied by the supply unit  54 , in the feed direction D 1  of the metal pipe material  20 , to cut the welded portion  15  from the inner periphery side of the metal pipe material  20 . In this case, after an excess portion  15   d  on the inner periphery side of the welded portion  15  is removed by the cutting unit  59 , the supply unit  54  can immediately form the plating layer  19  on the inner periphery-side surface  15   b  of the welded portion  15 . 
     As shown in  FIG.  4   , a welding nozzle  60  of the welding device  3  irradiates the outer periphery side of the metal pipe material  20  with a high frequency or the like, so that the abutted end portions  14   a  and  14   a  of the plate material  14  (refer to  FIG.  5 A ) are welded at a welding point WP. The position of the welding nozzle  60  is fixed in the feed direction D 1 . In this way, the upstream side of the welding point WP in the feed direction D 1  becomes a region where the welded portion  15  is not formed, and the downstream side of the welding point WP in the feed direction D 1  becomes a region where the welded portion  15  is formed. Here, immediately after the welding is performed at the welding point WP, the welded portion  15  has the excess portion  15   d  having an excess thickness on the inner periphery side (also refer to  FIG.  5 B ). On the other hand, the cutting unit  59  is disposed at a position spaced from the welding point WP to the downstream side in the feed direction D 1 . The cutting unit  59  is configured with a blade member or the like, which protrudes upward from the upper end portion of the rod  52 . In this way, the cutting unit  59  can cut the excess portion  15   d  protruding toward the inner periphery side of the welded portion  15 . In this way, the inner periphery-side surface  15   b  of the welded portion  15  is formed (also refer to  FIG.  5 C ). The injection nozzle  57  injects the plating material  58  at a position spaced from the cutting unit  59  to the downstream side in the feed direction D 1 . In this way, the plating layer  19  is formed on the surface  15   b  after cutting (also refer to  FIG.  5 D ). 
     Further, in the embodiment described above, a pipe-making apparatus in which the metal pipe material  20  is subjected to the plating treatment by the treatment device  50  after the welding device  3  and then is cut by the cutting device  4  has been described. However, the timing at which the treatment device  50  performs the plating treatment is not particularly limited. For example, after welding by the welding device  3 , the metal pipe material  20  may be cut by the cutting device  4  and then subjected to the plating treatment by the treatment device  50 . In this case, even in a case where it is difficult to install a new pipe-making apparatus or a case where it is difficult to modify an existing pipe-making apparatus, the treatment device  50  may be installed to a pipe-making apparatus in a retrofitting manner, so that there is an advantage that an existing pipe-making apparatus can be used as it is. 
     In the embodiment and modification examples described above, the supply unit  54  supplies the plating material  58  by using the injection nozzle  57 . The supply unit  54  may include a coating roller  157  instead of the injection nozzle  57 , as shown in  FIGS.  8 ,  9 , and  10   . Specifically,  FIG.  8    is a diagram showing a structure in which the coating roller  157  is applied to the treatment device  50  shown in  FIG.  2 A . As shown in  FIG.  8   , the coating roller  157  is provided at the end portion of the rod  52 . The coating roller  157  is a cylindrical member that is supported to be rotatable with a rotary shaft  158  as the center. The rotary shaft  158  is fixed to the rod  52 . The coating roller  157  is not fixed with respect to the rod  52 . Therefore, the coating roller  157  rotates around the rotary shaft  158  at the end portion of the rod  52 . 
     A portion of an outer peripheral surface  157   a  of the coating roller  157  is disposed at a position that is outside the rod  52  and close to the inner periphery-side surface  15   b  of the welded portion  15 . Another portion of the outer peripheral surface  157   a  of the coating roller  157  is disposed at a position in the rod  52 . The supply pipe  56  extends within the rod  52  to a position close to the outer peripheral surface  157   a  of the coating roller  157 . In this way, the supply pipe  56  can supply the plating material  58  to the outer peripheral surface  157   a  of the coating roller  157  within the rod  52 . When the metal pipe material  20  is fed in the feed direction D 1 , the coating roller  157  rotates. As a result, the plating material  58  supplied from the supply pipe  56  adheres to the inner periphery-side surface  15   b  of the welded portion  15  as the outer peripheral surface  157   a  rotates. 
       FIG.  9    is a drawing showing a configuration in which the coating roller  157  is applied to the treatment device  50  shown in  FIG.  3 A .  FIG.  10    is a drawing showing a configuration in which the coating roller  157  is applied to the treatment device  50  shown in  FIG.  4   . Each of the treatment devices  50  shown in  FIGS.  9  and  10    includes the coating roller  157  and the supply pipe  56  having the same configuration as in  FIG.  8   . 
     It should be understood that the invention is not limited to the above-described embodiment, but may be modified into various forms on the basis of the spirit of the invention. Additionally, the modifications are included in the scope of the invention.