Stainless steel sewage pipe hot rolling roll forming process

Abstract

The application discloses a stainless steel sewage pipe hot rolling roll forming process and relates to the technical field of stainless steel pipe hot rolling and roll forming. The process comprises the following steps: pipe blank preparation, heating and perforation, roll forming, fixed reducing and cooling, straightening and inspection, finishing and packaging. In the roll forming step, a continuous rolling mill is used, which comprises a base, a supporting seat, a supporting cylinder, a rotating cylinder and two rollers. The rotating cylinder is internally provided with an adjusting mechanism and a rotating mechanism. The adjusting mechanism is selectively engaged with a gear ring or a fixed ring through a hydraulic cylinder driving gear disc, and the space between the rollers is adjusted by cooperating with a motor. The rotating mechanism is locked after the angle of the rollers is adjusted by cooperating with a cross slot and an insertion slot. The application adjusts the space and the inclination angle of the rollers of each rack by gradient, so that the pipe blank bears a progressive rolling force, the problem of poor steel pipe precision and a rough surface in the prior art is solved, and the quality of the finished pipe is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of hot rolling and pressing technology for stainless steel pipes, specifically a hot rolling and pressing process for stainless steel sewage pipes. Background Technology

[0002] As a key component in sewage treatment facilities, building drainage systems, and industrial fields, the corrosion resistance and structural strength of stainless steel sewage pipes directly depend on the forming quality of the pipe material. In current pipe manufacturing processes, the rolling of seamless stainless steel pipes mainly relies on continuous rolling mills. Heated billets are progressively rolled using multiple stands of continuously arranged rolls to ultimately obtain pipes of the required specifications.

[0003] Existing continuous rolling mills typically employ a fixed roll installation design, where the roll spacing and angle on each stand remain relatively constant during rolling, making dynamic adjustment difficult based on tube deformation requirements. This rigid structure causes hollow tubes to experience intense instantaneous rolling pressure as they pass through each rolling stand, due to excessive deformation on a single stand. This results in excessive plastic deformation of the tube wall metal within a short period. Because of this concentrated deformation, uneven stress distribution easily occurs within the tube, leading to two prominent problems: firstly, the dimensional accuracy of the finished tube is difficult to guarantee, with outer diameter ellipticity and wall thickness tolerances often exceeding the allowable range for precision tubes; secondly, microscopic wrinkles or rough textures appear on the outer surface of the tube due to localized overload, affecting surface finish.

[0004] Furthermore, in practical applications of sewage transportation systems, the issue of fluid noise within the pipes is receiving increasing attention. Traditional stainless steel sewage pipes have smooth inner walls. When sewage flows through these pipes, friction between the fluid and the pipe wall, as well as internal turbulence, generates significant vibration and noise. This noise is particularly prevalent in high-rise building drainage systems, where it can be transmitted along the pipe structure into indoor spaces, impacting occupant comfort. To address this issue, some solutions attempt to add sound insulation layers or silencers after pipe installation. However, this approach increases construction complexity and cost, and its sound insulation effect is limited. Therefore, how to infuse noise reduction capabilities into the pipes during the manufacturing process remains a crucial technical challenge in this field.

[0005] Therefore, how to provide a continuous rolling mill that can flexibly adjust the working parameters of the rolls, realize the gradient setting of the roll gap and roll inclination angle between multiple stands, so that the billet is subjected to progressive and uniform rolling force during the rolling process, thereby ensuring the dimensional accuracy and surface quality of the finished pipe, and at the same time endowing the pipeline with noise reduction function through structural improvement, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a hot rolling and roll forming process for stainless steel sewage pipes in order to solve the technical problems in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a hot rolling and roll forming process for stainless steel sewage pipes, the specific steps of which are as follows:

[0008] Step 1: Tube blank preparation: Select a round tube blank as raw material and cut it into blanks of the required length;

[0009] Step 2, Heating and Piercing: The billet is heated to 1150℃-1250℃ in a ring furnace, and the heated billet is processed into a hollow tube by skew rolling piercing process;

[0010] Step 3: Roll forming: The hollow tube is rolled using a continuous rolling mill. By controlling the roll gap and roll inclination angle, the tube wall is uniformly thinned to the target thickness.

[0011] Step 4, Sizing and Cooling: The rolled steel pipe is subjected to the pipe removal process and the sizing or reduction process in sequence to determine the final outer diameter of the steel pipe; then the steel pipe is cooled by a water spray cooling tower.

[0012] Step 5, Straightening and Inspection: The cooled steel pipe is sent into a straightening machine for straightening; after straightening, spiral guide lines or spiral guide protrusions are welded on the inner wall of the steel pipe; the welded steel pipe is subjected to a hydrostatic test or flaw detection to ensure that the internal quality of the steel pipe meets the requirements.

[0013] Step Six: Finishing and Packaging: Pickling is performed on the qualified steel pipes to remove the surface oxide layer; then polishing is carried out; finally, the qualified products are packaged and put into storage.

[0014] The continuous rolling mill includes a base, with multiple support seats fixedly connected to the top of the base, and a support cylinder fixedly connected to the top of the support seats. A rotating cylinder is rotatably connected to the inner wall of the support cylinder, and two rolling rollers are arranged in the inner cavity of the rotating cylinder. The distance between the two rolling rollers is adjusted by an adjustment mechanism, and the angle of the rolling rollers is adjusted by a rotation mechanism.

[0015] As a further embodiment of the present invention: the adjusting mechanism includes a hydraulic cylinder, which is installed at the top of the base and located at one end of the support. The output end of the hydraulic cylinder is connected to a movable frame. A motor is installed on the inner wall of the movable frame. A gear plate is connected to the output end of the motor. A locking block is fixedly connected to the top of the movable frame. Limiting plates are fixedly connected to both ends of the rotating cylinder. The limiting plates are in contact with the outer wall of the support cylinder. A fixing ring is fixedly connected to the outer wall of one of the limiting plates. A rotating ring is rotatably connected to one end of the rotating cylinder. A gear ring is fixedly connected to one end of the rotating ring. A spur gear is rotatably connected to the top and bottom ends of the rotating ring on the outer wall of the rotating cylinder. A threaded rod is fixedly connected to one end of the spur gear. Movable grooves are opened at the top and bottom ends of the rotating cylinder. Movable plates are symmetrically slidably connected to the inner walls of the movable grooves. The threaded rod passes through the movable plate. A connecting rod is rotatably connected to the bottom end of the movable plate. The roller is rotatably connected to the bottom end of the connecting rod.

[0016] As a further embodiment of the present invention: the rotating mechanism includes a transverse groove, which is formed at the top and bottom of the inner wall of the support cylinder; slots are equidistantly formed on the outer circumference of the limiting plate; an insert plate is slidably connected to the inner wall of the slot; a rotating shaft is rotatably connected inside the insert plate; positioning blocks are fixedly connected to both ends of the rotating shaft; a positioning groove is formed on one side of the inner wall of the movable groove; a positioning plate extending to the outer wall of the movable plate is slidably connected inside the movable plate; a spring is connected between the positioning plate and the movable plate; a pressing block is slidably connected inside the movable plate at the top of the positioning plate; a pressing rod is fixedly connected to the top of the pressing block; and the pressing rod extends above the movable plate.

[0017] As a further embodiment of the present invention: the outer wall of the fixing ring is provided with a slot, and the top of the locking block engages with the slot.

[0018] As a further embodiment of the present invention: the top of the toothed disc is provided with a first tooth groove, and the outer wall of the toothed ring is provided with a first gear tooth, which meshes with the first tooth groove.

[0019] As a further embodiment of the present invention: the outer wall of the rotating ring is provided with a third tooth groove, which meshes with the spur gear.

[0020] As a further embodiment of the present invention: the outer wall of the movable plate is provided with a threaded hole, and the outer wall of the threaded rod is symmetrically provided with external threads, the external threads matching the threaded hole.

[0021] As a further embodiment of the present invention: a second tooth groove is provided at the bottom end of the toothed disc, and a second gear tooth is provided on the inner wall of the fixing ring, the second gear tooth meshing with the second tooth groove.

[0022] As a further embodiment of the present invention: the outer wall of the insert plate is in contact with the inner wall of the slot and the transverse groove; the end of the extrusion rod extending out of the movable plate is provided with a hemispherical surface; the top of the positioning plate is provided with an inclined surface; the bottom of the extrusion block is in contact with the inclined surface; the end of the positioning plate extending out of the outer wall of the movable plate is provided with a locking tooth; the locking tooth can be inserted into the positioning groove located on the side wall of the movable groove.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. This invention enables independent adjustment of the roll gap and angle, constructing a gradient rolling curve. The invention uses a hydraulic cylinder in the adjustment mechanism to drive the displacement of the movable frame, allowing the toothed disc to selectively engage with either the toothed ring or the fixed ring. Combined with the rotational drive of the motor, this allows for precise adjustment of the roll gap and roll angle of the two rolls. This design enables the roll parameters on multiple supports arranged along the rolling direction to be independently set according to process requirements, forming a gradient rolling mode with gradually decreasing roll gap and progressively changing roll angle. Compared to traditional fixed-parameter rolling methods, the billet experiences a progressive and uniform rolling force as it passes through each stand, avoiding stress concentration in the pipe wall caused by excessive single deformation, thus effectively solving the problem of insufficient dimensional accuracy in steel pipes.

[0025] 2. Optimize the roll displacement transmission structure to ensure synchronization and stability during adjustment. When adjusting the roll gap, the rotating ring connects to the gear ring and, driven by the motor, drives two spur gears and a threaded rod to rotate synchronously. The symmetrically arranged external threads on the threaded rod engage with the threaded holes of the two movable plates, driving the two movable plates to slide smoothly in opposite directions within the movable groove. This symmetrical screw transmission structure ensures that the two rolls always move symmetrically around the centerline of the tube, resulting in high concentricity of the roll gap adjustment and avoiding uneven wall thickness caused by roll misalignment. Simultaneously, the movable plates are rotatably connected to the rolls via connecting rods, ensuring free rotation of the rolls and precisely converting the linear motion of the movable plates into radial displacement of the rolls, resulting in good transmission rigidity and rapid response.

[0026] 3. A multi-stage locking mechanism is added to ensure the stability of rolling parameters. This invention incorporates a circumferential locking structure in the rotating mechanism, consisting of a slot, insert plate, transverse groove, and positioning block. After the roll angle is adjusted, the insert plate simultaneously inserts into the transverse groove of the support cylinder and the slot of the limiting plate. The rotating positioning block presses against the outer wall of the limiting plate, reliably fixing the rotating cylinder circumferentially and preventing roll angle deviation caused by vibration during rolling. Furthermore, the movable plate has a spring-return positioning plate structure. When the insert plate is inserted or the extrusion rod contacts the inner wall of the support cylinder, the extrusion rod drives the extrusion block downwards, pushing the positioning plate outwards to engage with the positioning groove on the side wall of the movable groove, thereby locking the axial position of the movable plate and preventing changes in the roll gap due to insufficient self-locking of the threaded rod or vibration. This dual locking mechanism ensures the long-term stability of rolling parameters, providing a reliable guarantee for obtaining high-precision, high-surface-quality steel pipes.

[0027] 4. Integrated inner wall flow guiding structure for noise reduction. This invention welds spiral flow guiding patterns or spiral flow guiding protrusions to the inner wall of the steel pipe after the straightening process. This structure guides the flow of sewage within the pipe after it is put into use, causing the fluid to advance along a spiral path. This effectively disrupts the laminar boundary layer and suppresses turbulent pulsation, thereby significantly reducing vibration noise generated by friction between the fluid and the pipe wall. Compared to traditional smooth inner wall pipes, the sewage pipe produced by this invention has superior noise reduction performance when transporting media, making it particularly suitable for building drainage systems with high noise requirements in residential environments. Without adding additional sound insulation measures, it solves the fluid noise problem from the source of pipe manufacturing, enhancing the product's added value and market competitiveness. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the internal structure of the support cylinder of the present invention;

[0030] Figure 3 This is a schematic diagram of the installation of the rotating cylinder of the present invention;

[0031] Figure 4 This is a schematic diagram of the installation of the rolls of the present invention;

[0032] Figure 5 This is a schematic diagram of the internal structure of the fixing ring of the present invention;

[0033] Figure 6 This is a schematic diagram of the installation of the insert plate of the present invention;

[0034] Figure 7 This is a schematic diagram of the internal structure of the insert plate of the present invention;

[0035] Figure 8This is a schematic diagram of the internal structure of the movable plate of the present invention.

[0036] In the diagram: 1. Base; 2. Support seat; 3. Support cylinder; 4. Rotating cylinder; 5. Roller; 6. Adjusting mechanism; 601. Hydraulic cylinder; 602. Movable frame; 603. Motor; 604. Gear disc; 605. Locking block; 606. Limiting plate; 607. Fixed ring; 608. Gear ring; 609. Rotating ring; 610. Spur gear; 611. Threaded rod; 612. Movable groove; 613. Movable plate; 614. Connecting rod; 7. Rotating mechanism; 701. Horizontal groove; 702. Slot; 703. Insert plate; 704. Rotating shaft; 705. Positioning block; 706. Positioning plate; 707. Spring; 708. Extrusion block; 709. Extrusion rod. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," and "set up" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The following describes embodiments of the invention based on its overall structure.

[0039] Please see Figures 1 to 8 In this embodiment of the invention, a hot rolling and roll forming process for stainless steel sewage pipes includes the following specific steps:

[0040] Step 1: Tube blank preparation: Select a round tube blank as raw material and cut it into blanks of the required length;

[0041] Step 2, Heating and Piercing: The billet is heated to 1150℃-1250℃ in a ring furnace, and the heated billet is processed into a hollow tube by skew rolling and piercing process;

[0042] Step 3, Roll forming: The hollow tube is rolled using a continuous rolling mill. By controlling the roll gap and roll inclination angle, the tube wall is uniformly thinned to the target thickness.

[0043] Step 4, Sizing and Cooling: The rolled steel pipe is subjected to the pipe removal process and the sizing or reduction process in sequence to determine the final outer diameter of the steel pipe; then the steel pipe is cooled by a water spray cooling tower.

[0044] Step 5, Straightening and Inspection: The cooled steel pipe is sent into a straightening machine for straightening; after straightening, spiral guide lines or spiral guide protrusions are welded on the inner wall of the steel pipe; the welded steel pipe is subjected to a hydrostatic test or flaw detection to ensure that the internal quality of the steel pipe meets the requirements.

[0045] Step Six: Finishing and Packaging: Pickling is performed on the qualified steel pipes to remove the surface oxide layer; then polishing is carried out; finally, the qualified products are packaged and put into storage.

[0046] Please refer to this carefully. Figures 1 to 5 The continuous rolling mill includes a base 1, with multiple support seats 2 fixedly connected to the top of the base 1, and a support cylinder 3 fixedly connected to the top of the support seat 2. A rotating cylinder 4 is rotatably connected to the inner wall of the support cylinder 3. Two rollers 5 are arranged in the inner cavity of the rotating cylinder 4. The distance between the two rollers 5 is adjusted by an adjustment mechanism 6, and the angle of the rollers 5 is adjusted by a rotation mechanism 7.

[0047] The adjusting mechanism 6 includes a hydraulic cylinder 601, which is mounted on the top of the base 1 and located at one end of the support 2. The output end of the hydraulic cylinder 601 is connected to a movable frame 602. A motor 603 is mounted on the inner wall of the movable frame 602, and a gear 604 is connected to the output end of the motor 603. A locking block 605 is fixedly connected to the top of the movable frame 602. Limiting plates 606 are fixedly connected to both ends of the rotating cylinder 4. The limiting plates 606 contact the outer wall of the support cylinder 3. A fixing ring 607 is fixedly connected to the outer wall of one limiting plate 606. A rotating ring 609 is rotatably connected to one end of the rotating ring 609. A toothed ring 608 is fixedly connected to one end of the rotating ring 609. A spur gear 610 is rotatably connected to the top and bottom ends of the rotating ring 609 on the outer wall of the rotating cylinder 4. A threaded rod 611 is fixedly connected to one end of the spur gear 610. Movable grooves 612 are opened at the top and bottom ends of the rotating cylinder 4. Movable plates 613 are symmetrically slidably connected to the inner wall of the movable grooves 612. The threaded rod 611 passes through the movable plate 613. A connecting rod 614 is rotatably connected to the bottom end of the movable plate 613. The roller 5 is rotatably connected to the bottom end of the connecting rod 614.

[0048] In this embodiment: when adjusting the gap between the two rolls 5, the hydraulic cylinder 601 is activated. The operation of the hydraulic cylinder 601 drives the movable frame 602 to move, and the movement of the movable frame 602 drives the toothed disc 604 and the locking block 605 to move synchronously until the top of the locking block 605 contacts the fixing ring 607, fixing the fixing ring 607, and thus fixing the position of the limiting plate 606 and the rotating cylinder 4, preventing rotation between the support cylinder 3 and the rotating cylinder 4. Figure 2 and 5 As shown in the diagram; simultaneously, the gear disc 604 and the gear ring 608 come into contact, and then the motor 603 is started. The motor 603 drives the gear disc 604 to rotate, which in turn drives the gear ring 608 to rotate. The gear ring 608 then drives the rotating ring 609 to rotate, which in turn drives the two spur gears 610 to rotate synchronously. The rotation of the spur gears 610 drives the threaded rod 611 to rotate, and the rotation of the threaded rod 611 drives the two movable plates 613 to move in opposite directions. The movement of the movable plates 613 drives the rollers 5 to move through the connecting rod 614. The two rollers 5 move in opposite directions, thereby adjusting the gap between the two rollers 5.

[0049] Please refer to this carefully. Figures 6 to 8The rotating mechanism 7 includes a transverse groove 701, which is formed at the top and bottom of the inner wall of the support cylinder 3. The outer wall of the limiting plate 606 is provided with slots 702 at equal intervals. The inner wall of the slot 702 is slidably connected to an insert plate 703. The insert plate 703 is rotatably connected to a rotating shaft 704. The two ends of the rotating shaft 704 are fixedly connected to positioning blocks 705. The inner wall of one side of the movable groove 612 is provided with a positioning groove. The movable plate 613 is slidably connected to a positioning plate 706 extending to the outer wall of the movable plate 613. A spring 707 is connected between the positioning plate 706 and the movable plate 613. The movable plate 613 is slidably connected to a pressing block 708 at the top of the positioning plate 706. The top of the pressing block 708 is fixedly connected to a pressing rod 709, which extends to the top of the movable plate 613.

[0050] In this embodiment: when adjusting the angle of the roll 5, the hydraulic cylinder 601 is activated to drive the movable frame 602 to move, causing the locking block 605 to separate from the fixed ring 607, thus releasing the angle fixation of the rotating cylinder 4, until the gear plate 604 contacts the fixed ring 607. The motor 603 is then activated, causing the gear plate 604 to rotate. The rotation of the gear plate 604 causes the fixed ring 607 to rotate, which in turn causes the limiting plate 606 to rotate, which in turn causes the rotating cylinder 4 to rotate, thereby adjusting the angle of the roll 5. After adjustment, the transverse groove 701 and the slot 702 are aligned, and the insert plate 703 is inserted into the transverse groove 701 and the slot 702, aligning the support cylinder 3 and the rotating cylinder 4. A fixing operation is performed to fix the angle of the roll 5. Then, the positioning block 705 is rotated. The two positioning blocks 705 rotate synchronously through the rotating shaft 704. The positioning block 705 rotates and contacts the outer wall of the limiting plate 606, positioning the insert plate 703 in the slot 702. At the same time, the top of the extrusion rod 709 contacts the inner wall of the support cylinder 3 or the outer wall of the insert plate 703. The extrusion rod 709 is displaced by force and enters the movable plate 613. The displacement of the extrusion rod 709 drives the extrusion block 708 to move. The displacement of the extrusion block 708 drives the positioning plate 706 to move. One end of the positioning plate 706 moves out of the movable plate 613 and engages with the positioning groove, thereby preventing the movable plate 613 from sliding in the movable groove 612 and causing the roll 5 to change displacement.

[0051] This allows for the adjustment of the roll gap and angle of the roll 5, thereby gradually reducing the roll gap and changing the angle on each support 2. This avoids the steel pipe being subjected to excessive pressure at one time, which could affect the dimensional accuracy of the steel pipe and prevent the surface from becoming too rough.

[0052] Please refer to this carefully. Figures 3 to 5 The outer wall of the fixing ring 607 is provided with a slot, and the top of the locking block 605 engages with the slot.

[0053] In this embodiment: the operation of the hydraulic cylinder 601 drives the movable frame 602 to move, and the movement of the movable frame 602 drives the gear plate 604 and the locking block 605 to move synchronously until the top of the locking block 605 contacts the fixing ring 607, fixing the fixing ring 607, and then fixing the position of the limiting plate 606 and the rotating cylinder 4 to prevent rotation between the support cylinder 3 and the rotating cylinder 4.

[0054] Please refer to this carefully. Figures 3 to 5 The top of the toothed disc 604 is provided with a first tooth groove, and the outer wall of the toothed ring 608 is provided with a first gear tooth, which meshes with the first tooth groove.

[0055] In this embodiment: the motor 603 drives the gear disk 604 to rotate, the gear disk 604 rotates and drives the gear ring 608 to rotate, and the gear ring 608 rotates and drives the rotating ring 609 to rotate.

[0056] Please refer to this carefully. Figures 3 to 5 The outer wall of the rotating ring 609 is provided with a third tooth groove, which meshes with the spur gear 610.

[0057] In this embodiment: the rotation of the gear ring 608 drives the rotation ring 609 to rotate, and the rotation of the rotation ring 609 drives the two spur gears 610 to rotate synchronously.

[0058] Please refer to this carefully. Figures 3 to 5 The outer wall of the movable plate 613 is provided with a threaded hole, and the outer wall of the threaded rod 611 is symmetrically provided with external threads, which match the threaded hole.

[0059] In this embodiment: the rotation of the spur gear 610 drives the threaded rod 611 to rotate, the rotation of the threaded rod 611 drives the two movable plates 613 to move in opposite directions, and the displacement of the movable plates 613 drives the roller 5 to move through the connecting rod 614.

[0060] Please refer to this carefully. Figures 6 to 8 The bottom end of the toothed disc 604 is provided with a second tooth groove, and the inner wall of the fixing ring 607 is provided with a second gear tooth, which meshes with the second tooth groove.

[0061] In this embodiment: the hydraulic cylinder 601 is activated to drive the movable frame 602 to move, causing the locking block 605 to separate from the fixed ring 607, thus removing the angle fixation of the rotating cylinder 4, until the gear plate 604 contacts the fixed ring 607, the motor 603 is activated, the motor 603 drives the gear plate 604 to rotate, the gear plate 604 drives the fixed ring 607 to rotate, the fixed ring 607 drives the limiting plate 606 to rotate, and the limiting plate 606 drives the rotating cylinder 4 to rotate.

[0062] Please refer to this carefully. Figures 6 to 8The outer wall of the insert plate 703 fits in close contact with the inner walls of the slot 702 and the transverse groove 701. The end of the extrusion rod 709 extending out of the movable plate 613 is provided with a hemispherical surface. The top of the positioning plate 706 is provided with an inclined surface. The bottom of the extrusion block 708 is in contact with the inclined surface. The end of the positioning plate 706 extending out of the outer wall of the movable plate 613 is provided with a locking tooth, which can be inserted into the positioning groove located on the side wall of the movable groove 612.

[0063] In this embodiment: the insert plate 703 is inserted into the transverse groove 701 and the slot 702 to fix the support cylinder 3 and the rotating cylinder 4. Then, the positioning block 705 is rotated and contacts both ends of the rotating cylinder 4, positioning the insert plate 703 in the slot 702. At the same time, the top end of the pressing rod 709 contacts the inner wall of the support cylinder 3 or the outer wall of the insert plate 703. The pressing rod 709 is displaced by force and enters the movable plate 613. The displacement of the pressing rod 709 drives the pressing block 708 to move. The displacement of the pressing block 708 drives the positioning plate 706 to move. One end of the positioning plate 706 moves out of the movable plate 613 and engages with the positioning groove, thereby preventing the movable plate 613 from sliding in the movable groove 612. The displacement of the extrusion rod 709 causes the extrusion block 708 to move, and the displacement of the extrusion block 708 causes the positioning plate 706 to move. One end of the positioning plate 706 moves out of the movable plate 613 and engages with the positioning groove, thereby preventing the movable plate 613 from sliding in the movable groove 612 and causing the roller 5 to change displacement.

[0064] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A hot rolling and roll forming process for stainless steel sewage pipes, characterized in that, Includes the following steps: Step 1: Tube blank preparation: Select a round tube blank as raw material and cut it into blanks of the required length; Step 2, Heating and Piercing: The billet is heated to 1150℃-1250℃ in a ring furnace, and the heated billet is processed into a hollow tube by skew rolling and piercing process; Step 3, Roll forming: The hollow tube is rolled using a continuous rolling mill. By controlling the roll gap and roll inclination angle, the tube wall is uniformly thinned to the target thickness. Step 4, Sizing and Cooling: The rolled steel pipe is subjected to the pipe removal process and the sizing or reduction process in sequence to determine the final outer diameter of the steel pipe; then the steel pipe is cooled by a water spray cooling tower. Step 5, Straightening and Inspection: The cooled steel pipe is sent into a straightening machine for straightening; after straightening, spiral guide lines or spiral guide protrusions are welded on the inner wall of the steel pipe; the welded steel pipe is subjected to a hydrostatic test or flaw detection to ensure that the internal quality of the steel pipe meets the requirements. Step Six: Finishing and Packaging: Pickling is performed on the qualified steel pipes to remove the surface oxide layer; then polishing is carried out; finally, the qualified products are packaged and put into storage. The continuous rolling mill includes a base (1), a plurality of support seats (2) are fixedly connected to the top of the base (1), a support cylinder (3) is fixedly connected to the top of the support seat (2), a rotating cylinder (4) is rotatably connected to the inner wall of the support cylinder (3), and two rollers (5) are provided in the inner cavity of the rotating cylinder (4). The distance between the two rollers (5) is adjusted by an adjustment mechanism (6), and the angle of the rollers (5) is adjusted by a rotation mechanism (7). The adjusting mechanism (6) includes a hydraulic cylinder (601), which is installed at the top of the base (1) and located at one end of the support (2). The output end of the hydraulic cylinder (601) is connected to a movable frame (602). A motor (603) is installed on the inner wall of the movable frame (602). The output end of the motor (603) is connected to a gear plate (604). A locking block (605) is fixedly connected to the top of the movable frame (602). Limiting plates (606) are fixedly connected to both ends of the rotating cylinder (4). The limiting plates (606) are in contact with the outer wall of the support cylinder (3). A fixing ring (607) is fixedly connected to the outer wall of one of the limiting plates (606). The rotating cylinder ( 4) One end of the rotating cylinder (4) is rotatably connected to a rotating ring (609), and one end of the rotating ring (609) is fixedly connected to a toothed ring (608). The outer wall of the rotating cylinder (4) is rotatably connected to the top and bottom ends of the rotating ring (609) with a spur gear (610). One end of the spur gear (610) is fixedly connected to a threaded rod (611). The top and bottom ends of the rotating cylinder (4) are provided with movable grooves (612). The inner wall of the movable groove (612) is symmetrically slidably connected to a movable plate (613). The threaded rod (611) passes through the movable plate (613). The bottom end of the movable plate (613) is rotatably connected to a connecting rod (614). The roller (5) is rotatably connected to the bottom end of the connecting rod (614). The rotating mechanism (7) includes a transverse groove (701), which is formed at the top and bottom of the inner wall of the support cylinder (3). The outer wall of the limiting plate (606) is provided with slots (702) at equal intervals. The inner wall of the slot (702) is slidably connected to an insert plate (703). The insert plate (703) is rotatably connected to a rotating shaft (704). The two ends of the rotating shaft (704) are fixedly connected to positioning blocks (705). The inner wall of one side of the movable groove (612) is provided with a positioning block. The movable plate (613) is slidably connected to a positioning plate (706) extending to the outer wall of the movable plate (613). A spring (707) is connected between the positioning plate (706) and the movable plate (613). An extrusion block (708) is slidably connected to the top of the positioning plate (706) inside the movable plate (613). An extrusion rod (709) is fixedly connected to the top of the extrusion block (708). The extrusion rod (709) extends above the movable plate (613). The top of the toothed disc (604) is provided with a first tooth groove, and the outer wall of the toothed ring (608) is provided with a first gear tooth, which meshes with the first tooth groove. The outer wall of the rotating ring (609) is provided with a third tooth groove, which meshes with the spur gear (610); The bottom end of the toothed disc (604) is provided with a second tooth groove, and the inner wall of the fixing ring (607) is provided with a second gear tooth, which meshes with the second tooth groove.

2. The hot rolling and roll forming process for stainless steel sewage pipes according to claim 1, characterized in that, The outer wall of the fixing ring (607) is provided with a slot, and the top of the locking block (605) engages with the slot.

3. The hot rolling and roll forming process for stainless steel sewage pipes according to claim 1, characterized in that, The outer wall of the movable plate (613) is provided with a threaded hole, and the outer wall of the threaded rod (611) is symmetrically provided with external threads, which are matched with the threaded hole.

4. The hot rolling and roll forming process for stainless steel sewage pipes according to claim 1, characterized in that, The outer wall of the insert plate (703) is in contact with the inner wall of the slot (702) and the transverse groove (701). The end of the extrusion rod (709) extending out of the movable plate (613) is provided with a hemispherical surface. The top of the positioning plate (706) is provided with an inclined surface. The bottom of the extrusion block (708) is in contact with the inclined surface. The end of the positioning plate (706) extending out of the outer wall of the movable plate (613) is provided with a locking tooth. The locking tooth can be inserted into the positioning groove located on the side wall of the movable groove (612).

Images