Process for improving pickling quality of hot-rolled ferritic stainless steel coils

Abstract

The application discloses a process for improving pickling quality of a ferrite stainless steel hot-rolled coil surface, and comprises the following steps: 1) unwinding and welding; 2) annealing; 3) scale breaking and shot blasting; 4) mixed acid pickling; 5) brushing pickling; 6) rinsing; and 7) drying. In the step 5) of brushing pickling, the distance between the moving plate, the circular brush and the hollow frame is adjusted, the interval between the circular brushes on different groups of moving plates is adjusted, the brushing frequency and interval of the strip steel are adjusted, the adjustment can be adapted according to the amount of the oxide skin on the surface of the strip steel, the oxide skin can be removed while the friction amount between the circular brush and the surface of the strip steel is reduced, too much wear on the surface of the strip steel is avoided, and the finished product effect of the strip steel is affected.

Description

Technical Field

[0001] This invention belongs to the technical field of pickling ferritic stainless steel strip, and specifically relates to a process for improving the surface pickling quality of hot-rolled ferritic stainless steel coils. Background Technology

[0002] Ferritic stainless steel has a body-centered cubic crystal structure and good resistance to oxidation, corrosion and chloride corrosion cracking. It is commonly used in household appliances such as washing machines, dryers and dishwashers, and can also be used as decorative materials. In the pickling process of ferritic stainless steel, a mixed acid solution is usually used to remove the oxide scale on its surface and to form a passivation film on the surface of the strip steel.

[0003] A search revealed a hot-rolled stainless steel annealing and pickling line brush washing roller swing device with application number CN202123155939.X, comprising a support mechanism, a brush mechanism, an adjustment mechanism, and a swing mechanism. The support mechanism has a brush mechanism on one side, and adjustment mechanisms are provided on both sides of the brush mechanism. The adjustment mechanism has a swing mechanism on one side. The adjustment mechanism includes a fixed frame, an arc plate, a limit slide groove, a connecting slide plate, an ear block, a rotating rod, a sleeve block, a round rod, a second frame, a second motor, a reciprocating screw, a sleeve plate, and a docking hole. The top of the fixed frame and the end of the arc plate are fixedly connected. The following problems exist in the processing: 1) When the round brush removes the oxide scale on the surface of the strip steel, it needs to be in continuous contact with the strip steel. When the residual oxide scale is small, it will increase the friction between the round brush and the strip steel, resulting in excessive wear on the surface of the strip steel and affecting the finished product effect of the strip steel. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a process to improve the pickling quality of hot-rolled ferritic stainless steel coils, so as to solve the problem of excessive wear on the surface of strip steel.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A process for improving the pickling quality of hot-rolled ferritic stainless steel coils includes the following steps:

[0007] Step 1) Uncoiling and Welding: The stainless steel hot-rolled coil is fed into the uncoiling machine for uncoiling, and the two stainless steel hot-rolled coils are butt-welded together and fixed by the welding device.

[0008] Step 2) Annealing: The stainless steel strip is annealed and cooled using an annealing device;

[0009] Step 3) Descaling and shot blasting: The stainless steel strip after annealing and cooling is subjected to descaling and shot blasting operations using a descaling device and a shot blasting device to remove the oxide scale on the strip.

[0010] Step 4) Mixed acid pickling: Immerse the strip steel in a mixed acid solution with a flow acid concentration of 80-120 g / L and a nitric acid concentration of 90-110 g / L for pickling. The concentration of metal ions in the acid solution is 25-35 g / L. The pickling temperature is 45-55℃ and the pickling time is 30-40 minutes.

[0011] Step 5) Brushing and pickling: A mixed acid solution with a flow acid concentration of 70-100 g / L, a nitric acid concentration of 80-100 g / L, a metal ion concentration of 20-30 g / L, and a pickling temperature of 40-50℃ is intermittently fed to the surface of the strip steel through a pickling device. At the same time, a circular brush pickles the surface of the strip steel in the acid solution intervals. The circular brush rotates at a speed of 500-800 rpm, and the brushing time is 30-40 minutes.

[0012] Step 6) Rinsing: Rinse the surface of the strip steel with acid by spraying water;

[0013] Step 7) Drying: Dry the stainless steel strip surface by using a drying mechanism to remove residual water stains.

[0014] The pickling device in step 5) includes an upper support platform, a lower support platform, support columns, pinch rollers, a pickling tank, an acid scraping mechanism, and a brushing mechanism. The upper support platform and the lower support platform are connected by several support columns. Pinch rollers are provided on the support columns. A pickling tank is provided on one side of the upper support platform. A brushing mechanism is provided on one side of the pickling tank. A scraping mechanism is provided on both the pickling tank and the brushing mechanism. Another set of brushing mechanisms is provided on one side of the lower support platform. A scraping mechanism is provided on one side of the brushing mechanism.

[0015] The brushing mechanism includes a sliding box, support legs, a first guide rod, a first lead screw, a first motor, a first support arm, a second support arm, a hydraulic cylinder, a connecting arm, a connecting plate, a hollow frame, a rotating column, a second motor, a sliding frame, a rotating rod, a fixed rod, a fourth motor, an adjusting arm, an adjusting plate, a rotating plate, a rotating shaft, a third motor, a moving plate, a soft baffle, a first electric push rod, a sliding rod, and a circular brush. Both ends of the hollow frame are fixedly connected to the rotating column, and the rotating column and the connecting plate are movably connected. One set of rotating columns and the output end of the second motor are connected via a gearbox. The connecting plate and the connecting arm are fixedly connected. The connecting arm and the second support arm are connected. The second support arm and the first support arm are slidably connected. One side of the first support arm is connected to the hydraulic cylinder, and the output end of the hydraulic cylinder is connected to the second support arm. The bottom of each first support arm is slidably connected to the sliding box. One set of first support arms and the first lead screw are threaded together, and the other set of first support arms is slidably connected to the first guide rod. Both ends of the first lead screw are movably connected to the sliding box. One end of the first lead screw is connected to the output end of the first motor. Both ends of the first guide rod are connected to the sliding box. The bottom of the sliding box... The device is fixedly connected to several supporting legs. The outer side of the hollow frame is slidably connected to two sets of symmetrically distributed sliding frames. The sliding frames and the two ends of the rotating rod are connected by two sets of oppositely oriented threads. The sliding frames and the fixed rod are slidably connected. The two ends of the rotating rod are movably connected to the hollow frame. The middle of the rotating rod is connected to the output end of the fourth motor via a gearbox. The fourth motor is connected to the hollow frame. The two ends of the fixed rod are connected to the hollow frame. The outer side of the center of the sliding frame is movably connected to one end of several adjusting arms. The other end of the adjusting arm is movably connected to the adjusting plate. The adjusting plate is equipped with several first electric push rods. The output end of the first electric push rod is connected to the moving plate. One side of the moving plate is fixedly connected to several sliding rods. The sliding rods are slidably connected to the adjusting plate. The moving plate is movably connected to several rotating shafts. One end of the rotating shaft is fixedly connected to a rotating disk. A circular brush is provided on one side of the rotating disk. The rotating shafts are connected to each other via chains and sprockets. Two sets of rotating shafts are connected to the output end of the third motor via chains and sprockets. The third motor is located at both ends of the moving plate. The adjusting plate has notches corresponding to the third motor. Soft baffles are provided on both sides of the moving plate, and the soft baffles are connected to the moving plate and the adjusting plate respectively.

[0016] Preferably, the adjustment plate is provided with a plurality of through square holes.

[0017] Preferably, the scrubbing mechanism further includes an acid supply pipe, a connecting box, a fixed block, a fixed box, a rotating box, a connecting hose, a pipe joint, an acid supply branch pipe, an acid flow hole, an outer sleeve, a pipe opening, a connecting plate, a connecting shaft, a connecting frame, a moving block, a follower frame, a second guide rod, a second spring, a follower ring, and an insertion rod. One side of the fixed block is fixedly connected to the connecting arm, and the other side of the fixed block is fixedly connected to the connecting box. One side of the connecting box is connected to the acid supply pipe, and the other side of the connecting box is connected to the fixed box. The fixed box and the rotating box are movably connected. The outer center of the rotating box is connected to one end of several connecting hoses, and the other end of the connecting hoses is connected to the pipe joint. The pipe joint is movably connected to one end of the acid supply branch pipe. The acid supply branch pipe is provided with several acid flow holes, and the acid flow holes face vertically. Downward, the other end of the acid supply branch pipe is fixedly connected to the connecting plate, the connecting plate is fixedly connected to the connecting shaft, the connecting shaft is movably connected to the connecting frame, the connecting frame is slidably connected to the moving block, the moving block and the second guide rod and the follower frame are slidably connected, the second guide rod and the follower frame are fixedly connected, a second spring is provided on the outside of the second guide rod, the follower frame and the follower ring are fixedly connected, the follower ring and the connecting plate are movably connected, the outside of the acid supply branch pipe and the outer sleeve are movably connected, the outer sleeve is set between the adjusting plates and alternately set with the adjusting plates, the outer sleeve has a pipe opening, the pipe opening faces the centrifugal direction of the follower ring, the outside of the outer sleeve is fixedly connected to several insert rods, the insert rods are slidably connected to the square holes on the adjusting plate, and the insert rods on the outside of different outer sleeves are staggered.

[0018] Preferably, the scrubbing mechanism further includes an acid receiving tank and an acid drain pipe. The acid receiving tank is located below the sliding box, and an acid drain pipe is provided on one side of the acid receiving tank.

[0019] Preferably, the acid scraping mechanism includes a fixed column, an acid scraping plate, a sliding sleeve, a first spring, and a limiting plate. Both ends of the acid scraping plate are fixedly connected to the sliding sleeve, the sliding sleeve and the fixed column are slidably connected, a limiting plate is provided on the outside of the fixed column, and a first spring is provided on the outside of the fixed column. The first spring is disposed between the limiting plate and the sliding sleeve.

[0020] Preferably, the pickling tank includes a pickling box and guide rollers. The pickling box is located on one side of the upper support platform. An acid inlet pipe and an acid outlet pipe are respectively provided on one side of the pickling box. Several guide rollers are provided inside the pickling box.

[0021] The advantages of this invention compared to existing technologies are as follows:

[0022] 1) The fourth motor drives the rotating rod to rotate through the gearbox. The rotating rod drives the sliding frame to slide on the hollow frame through two sets of opposite threads. At the same time, the distance between the sliding frames is adjusted. Simultaneously, the adjusting arm drives the adjusting plate to move, adjusting the distance between the adjusting plate and the hollow frame. This adjusts the distance between the moving plate and the circular brush and the hollow frame. At the same time, the distance between the circular brushes on different sets of moving plates is adjusted to adjust the brushing frequency and interval of the strip steel. This can be adjusted according to the amount of oxide scale on the strip steel surface. While ensuring the removal of oxide scale, the friction between the circular brush and the strip steel surface is reduced, avoiding excessive wear on the strip steel surface and affecting the finished product effect of the strip steel.

[0023] 2) The acid supply branch pipe rotates inside the outer sleeve, keeping the acid flow hole vertically downward. When the acid flow hole aligns with the pipe opening, the acid flows through the acid flow hole to the strip steel, creating a certain interval between the acid flowing from the sulfuric acid hole to the strip steel. This allows time for the acid to react with the oxide scale, improving the pickling effect and reducing the amount of acid used, significantly reducing the amount of waste acid generated. Simultaneously, it works in conjunction with the round brush, promoting contact between the acid and the oxide scale and improving the pickling effect. When the distance between the adjusting plate and the hollow frame changes, the insert rod slides adaptively within the square hole, causing the outer sleeve to move accordingly. This movement, changing with the adjusting plate, simultaneously drives the acid supply branch pipe, connecting plate, and connecting shaft to move, allowing the connecting frame to slide adaptively on the moving block. Therefore, when the spacing between the round brushes is adjusted, the spacing between the acid supply branch pipes also adjusts accordingly. The spacing between the acid supply branch pipes and the spacing between the round brushes on different moving plates can be adjusted based on the amount of oxide scale on the strip steel surface, thereby adjusting the intensity of brushing and pickling. Attached Figure Description

[0024] Appendix Figure 1 This is a schematic diagram of the pickling device structure in a process for improving the surface pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0025] Appendix Figure 2 This is a schematic diagram of the pickling tank structure in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0026] Appendix Figure 3 This is a schematic diagram of the brushing mechanism in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0027] Appendix Figure 4 This is a schematic diagram of the acid scraping mechanism in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0028] Appendix Figure 5 This is a schematic diagram of the other side of the brushing mechanism in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0029] Appendix Figure 6 It is attached Figure 5 Enlarged view of point A in the middle;

[0030] Appendix Figure 7 This is a schematic diagram of the internal structure of the brushing mechanism in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0031] Appendix Figure 8 This is a schematic diagram of the internal structure of the hollow frame in a process for improving the surface pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0032] Appendix Figure 9 This is a schematic diagram of the acid flow hole structure in a process for improving the pickling quality of hot-rolled ferritic stainless steel coils according to the present invention.

[0033] In the diagram: 1. Upper support platform; 2. Lower support platform; 3. Support column; 4. Pinch roller; 5. Pickling tank; 51. Pickling box; 52. Guide roller; 6. Acid scraping mechanism; 61. Fixed column; 62. Acid scraping plate; 63. Sliding sleeve; 64. First spring; 65. Limiting plate; 7. Brushing mechanism; 71. Sliding box; 72. Support leg; 73. First guide rod; 74. First lead screw; 75. First motor; 76. First support arm; 761. Second support arm; 762. Hydraulic cylinder; 77. Connecting arm; 78. Connecting plate; 79. Hollow frame; 701. Rotating column; 702. Second motor; 703. Sliding frame; 7031. Rotating rod; 7032. Fixed rod; 7033. Fourth motor; 704. Adjusting arm; 70 5. Adjusting plate; 706. Square hole; 707. Rotating disc; 708. Rotating shaft; 709. Third motor; 711. Moving plate; 712. Soft baffle; 713. First electric push rod; 714. Sliding rod; 715. Circular brush; 81. Acid supply pipe; 82. Connecting box; 83. Fixing block; 84. Fixing box; 85. Rotating box; 86. Connecting hose; 87. Pipe joint; 88. Acid supply branch pipe; 89. Acid flow hole; 801. Outer sleeve; 802. Pipe opening; 803. Connecting plate; 804. Connecting shaft; 805. Connecting frame; 806. Moving block; 807. Follower frame; 8071. Second guide rod; 808. Second spring; 809. Follower ring; 811. Insert rod; 9. Acid receiving tank; 91. Acid discharge pipe. Detailed Implementation

[0034] To facilitate understanding by those skilled in the art, the following is a detailed explanation in conjunction with the appendix. Figure 1-9 The technical solution of the present invention will be further described in detail below.

[0035] Example 1:

[0036] A process for improving the pickling quality of hot-rolled ferritic stainless steel coils includes the following steps:

[0037] Step 1) Uncoiling and Welding: The stainless steel hot-rolled coil is fed into the uncoiling machine for uncoiling, and the two stainless steel hot-rolled coils are butt-welded together and fixed by the welding device.

[0038] Step 2) Annealing: The stainless steel strip is annealed and cooled using an annealing device;

[0039] Step 3) Descaling and shot blasting: The stainless steel strip after annealing and cooling is subjected to descaling and shot blasting operations using a descaling device and a shot blasting device to remove the oxide scale on the strip.

[0040] Step 4) Mixed acid pickling: Immerse the strip steel in a mixed acid solution with a flow acid concentration of 83 g / L and a nitric acid concentration of 95 g / L for pickling. The concentration of metal ions in the acid solution is 26 g / L. The pickling temperature is 46℃ and the pickling time is 33 minutes.

[0041] Step 5) Brushing and pickling: A mixed acid solution with a flow acid concentration of 75g / L, a nitric acid concentration of 84g / L, an acid solution metal ion concentration of 22g / L, and a pickling temperature of 42℃ is fed to the strip surface at intervals through the pickling device. At the same time, a circular brush pickles the strip surface in the acid solution intervals. The circular brush rotates at a speed of 550rpm and the brushing time is 33 minutes.

[0042] Step 6) Rinsing: Rinse the surface of the strip steel with acid by spraying water;

[0043] Step 7) Drying: Dry the stainless steel strip surface by using a drying mechanism to remove residual water stains.

[0044] The pickling device in step 5) includes an upper support platform 1, a lower support platform 2, support columns 3, pinch rollers 4, a pickling tank 5, an acid scraping mechanism 6, and a brushing mechanism 7. The upper support platform 1 and the lower support platform 2 are connected by several support columns 3. The support columns 3 are equipped with pinch rollers 4. The upper support platform 1 is equipped with a pickling tank 5 on one side, and the pickling tank 5 is equipped with a brushing mechanism 7 on one side. Both the pickling tank 5 and the brushing mechanism 7 are equipped with an acid scraping mechanism 6 on one side. The lower support platform 2 is equipped with another set of brushing mechanisms 7 on one side, and the brushing mechanism 7 is equipped with an acid scraping mechanism 6 on one side.

[0045] After the strip steel coil is uncoiled and straightened, it undergoes preliminary soaking and pickling in pickling tank 5 to remove the oxide scale on the strip steel. Then, it passes through the acid scraping mechanism 6 to scrape off the acid on the strip steel. The pinch roller 4 provides power for the movement of the strip steel. The strip steel then passes through the brushing mechanism 7 on the upper support platform 1 to brush off the oxide scale and pickle it. After passing through the acid scraping mechanism 6 to scrape off the acid on the strip steel, the strip steel then passes through the brushing mechanism 7 on the lower support platform 2 to brush off the oxide scale on the other side of the strip steel. After passing through the acid scraping mechanism 6 to scrape off the acid on the strip steel, the strip steel passes through the brushing mechanism 7 on the lower support platform 2 to brush off the oxide scale on the other side of the strip steel.

[0046] The brushing mechanism 7 includes a sliding box 71, support legs 72, a first guide rod 73, a first lead screw 74, a first motor 75, a first support arm 76, a second support arm 761, a hydraulic cylinder 762, a connecting arm 77, a connecting plate 78, a hollow frame 79, a rotating column 701, a second motor 702, a sliding frame 703, a rotating rod 7031, a fixed rod 7032, a fourth motor 7033, an adjusting arm 704, an adjusting plate 705, a rotating plate 707, a rotating shaft 708, a third motor 709, a moving plate 711, a soft baffle 712, a first electric push rod 713, a sliding rod 714, and a circular brush 715. Both ends of the hollow frame 79 are fixedly connected to the rotating column 701, and the rotating column 701 and the connecting plate 78 are movably connected. The rotating column 701 and the output end of the second motor 702 are connected via a gearbox. The connecting plate 78 and the connecting arm 77 are fixedly connected. The connecting arm 77 is connected to the second support arm 761. The second support arm 761 and the first support arm 76 are slidably connected. One side of the first support arm 76 is connected to the hydraulic cylinder 762. The output end of the hydraulic cylinder 762 is connected to the second support arm 761. The bottom of each first support arm 76 is slidably connected to the sliding box 71. One set of first support arms 76 and the first lead screw 74 are connected by threads. Another set of first support arms 76 and the first guide rod 73 are slidably connected. Both ends of the first lead screw 74 are movably connected to the sliding box 71. One end of the first lead screw 74 is connected to the output end of the first motor 75. Both ends of the first guide rod 73 are connected to the sliding box 71. 1. The bottom is fixedly connected to several supporting legs 72. The outer side of the hollow frame 79 is slidably connected to two sets of symmetrically distributed sliding frames 703. The two ends of the sliding frame 703 and the rotating rod 7031 are connected by two sets of threads in opposite directions. The sliding frame 703 is slidably connected to the fixed rod 7032. The two ends of the rotating rod 7031 are movably connected to the hollow frame 79. The middle of the rotating rod 7031 is connected to the output end of the fourth motor 7033 through a gearbox. The fourth motor 7033 is connected to the hollow frame 79. The two ends of the fixed rod 7032 are connected to the hollow frame 79. The outer side of the center of the sliding frame 703 is movably connected to one end of several adjusting arms 704. The other end of the adjusting arm 704 is movably connected to the adjusting plate 705. The adjusting plate 705 is provided with several first electric push rods 713. The output end of the push rod 713 is connected to the movable plate 711. One side of the movable plate 711 is fixedly connected to several sliding rods 714. The sliding rods 714 are slidably connected to the adjusting plate 705. Several rotating shafts 708 are movably connected to the movable plate 711. One end of the rotating shaft 708 is fixedly connected to the rotating disk 707. A round brush 715 is provided on one side of the rotating disk 707. The rotating shafts 708 are connected to each other by chains and sprockets. Two sets of rotating shafts 708 are connected to the output end of the third motor 709 by chains and sprockets. The third motor 709 is located at both ends of the movable plate 711. The adjusting plate 705 has a notch corresponding to the third motor 709. Soft baffles 712 are provided on both sides of the movable plate 711. The soft baffles 712 are connected to the movable plate 711 and the adjusting plate 705 respectively.

[0047] The second motor 702 drives the rotating column 701 to rotate on the connecting plate 78 via a gearbox, which in turn drives the hollow frame 79, sliding frame 703, adjusting arm 704, adjusting plate 705, moving plate 711, rotating disk 707, and round brush 715 to rotate. Simultaneously, the third motor 709 drives the rotating shaft 708, rotating disk 707, and round brush 715 to rotate via a chain wheel and chain. The round brush 715 rotates while simultaneously brushing away the oxide scale from the strip surface. The fourth motor 7033 drives the rotating rod 7031 to rotate via a gearbox. The rotating rod 7031 drives the sliding frame 703 to slide on the hollow frame 79 via two sets of oppositely oriented threads, adjusting the distance between the sliding frames 703. Simultaneously, the adjusting arm 704 moves the adjusting plate 705 to adjust the distance between the adjusting plate 705 and the hollow frame 79. This adjusts the distance between the moving plate 711 and the circular brush 715 and the hollow frame 79, and simultaneously adjusts the spacing between the circular brushes 715 on different sets of moving plates 711, thereby adjusting the brushing frequency and interval of the strip steel. This can be adapted to the amount of oxide scale on the strip steel surface, ensuring oxide scale removal while reducing the friction between the circular brushes 715 and the strip steel surface. At the same time, the first motor 75 provides power for the rotation of the first lead screw 74, which in turn drives the first support arm 76 to slide within the sliding box 71, thereby driving the second support arm 761, connecting arm 77, connecting plate 78, hollow frame 79, and circular brushes 715 to reciprocate, brushing away the oxide scale on the strip steel surface. Simultaneously, the hydraulic cylinder 762 provides power for the second support arm 761 to slide on the first support arm 76, thereby adjusting the distance between the circular brushes 715 and the strip steel.

[0048] The adjusting plate 705 is provided with several through square holes 706.

[0049] The scrubbing mechanism 7 further includes an acid supply pipe 81, a connecting box 82, a fixing block 83, a fixing box 84, a rotating box 85, a connecting hose 86, a pipe joint 87, an acid supply branch pipe 88, an acid flow hole 89, an outer sleeve 801, a pipe opening 802, a connecting plate 803, a connecting shaft 804, a connecting frame 805, a moving block 806, a follower frame 807, a second guide rod 8071, a second spring 808, a follower ring 809, and an insertion rod 811. One side of the fixing block 83 is fixedly connected to the connecting arm 77. The other side of the fixed block 83 is fixedly connected to the connecting box 82. One side of the connecting box 82 is connected to the acid supply pipe 81, and the other side of the connecting box 82 is connected to the fixed box 84. The fixed box 84 is movably connected to the rotating box 85. The outer center of the rotating box 85 is connected to one end of several connecting hoses 86. The other end of the connecting hoses 86 is connected to the pipe connector 87. The pipe connector 87 is movably connected to one end of the acid supply branch pipe 88. The acid supply branch pipe 88 is provided with several acid flow holes 89, which face vertically downwards. The other end is fixedly connected to the connecting plate 803. The connecting plate 803 is fixedly connected to the connecting shaft 804. The connecting shaft 804 is movably connected to the connecting frame 805. The connecting frame 805 is slidably connected to the moving block 806. The moving block 806 is slidably connected to the second guide rod 8071 and the follower frame 807. The second guide rod 8071 and the follower frame 807 are fixedly connected. A second spring 808 is provided on the outer side of the second guide rod 8071. The follower frame 807 and the follower ring 809 are fixedly connected. The follower ring 809 and the connecting... The receiving plate 78 is movably connected, the outer side of the acid supply branch pipe 88 and the outer sleeve 801 are movably connected, the outer sleeve 801 is set between the adjusting plates 705 and alternately set with the adjusting plates 705, the outer sleeve 801 is provided with a pipe opening 802, the pipe opening 802 is oriented in the centrifugal direction of the follower ring 809, the outer side of the outer sleeve 801 is fixedly connected to several insert rods 811, the insert rods 811 are slidably connected to the square holes 706 on the adjusting plates 705, and the insert rods 811 on the outer sides of different outer sleeves 801 are staggered;

[0050] Acid is supplied through acid supply pipe 81 and connecting box 82 into the inner side of fixed box 84 and rotating box 85, and then through connecting hose 86 and pipe joint 87 into acid supply branch pipe 88. When adjusting plate 705 rotates with rotating column 701, adjusting plate 705 drives outer sleeve 801 and acid supply branch pipe 88 to rotate through insert rod 811. Acid supply branch pipe 88 drives connecting plate 803, connecting shaft 804, connecting frame 805, moving block 806, and follower frame 807 to rotate. Follower frame 807 rotates on connecting plate 78. When the connecting shaft 804 rotates on the connecting frame 805, the connecting shaft 804 and the connecting plate 803 react with the acid supply branch pipe 88, causing the acid supply branch pipe 88 to rotate within the outer sleeve 801, while keeping the acid flow hole 89 vertically downward. When the acid flow hole 89 aligns with the pipe opening 802, the acid flows through the acid flow hole 89 to the strip steel. Because there is a certain interval between the acid supply branch pipes 88, there is a certain interval between the acid flowing from the sulfuric acid holes to the strip steel, allowing time for the acid to react with the oxide scale. After a period of reaction... The next wave of acid washes away the previous acid and replaces it with fresh acid, improving the pickling effect and reducing the amount of acid used. Simultaneously, it works in conjunction with the circular brush 715 to scrub the acid and oxide scale, promoting contact between the acid and oxide scale and enhancing the pickling effect. When the distance between the adjusting plate 705 and the hollow frame 79 changes, the insertion rod 811 slides adaptively within the square hole 706, causing the outer sleeve 801 to move accordingly, changing based on the adjustment plate 705. The acid supply branch pipe 88, connecting plate 803, and connecting shaft 804 are moved, causing the connecting frame 805 to slide adaptively on the moving block 806. Therefore, when the spacing between the circular brushes 715 is adjusted, the spacing between the acid supply branch pipes 88 will also be adjusted accordingly. The spacing between the acid supply branch pipes 88 and the spacing between the circular brushes 715 on different moving plates can be adjusted according to the amount of oxide scale on the strip surface, thereby adjusting the time interval of acid flow to the strip and the time interval of brushing the strip, thus adjusting the intensity of brushing and pickling.

[0051] The scrubbing mechanism 7 also includes an acid receiving tank 9 and an acid drain pipe 91. The acid receiving tank 9 is located below the sliding box 71, and the acid drain pipe 91 is provided on one side of the acid receiving tank 9.

[0052] The acid scraping mechanism 6 includes a fixed column 61, an acid scraping plate 62, a sliding sleeve 63, a first spring 64, and a limiting plate 65. Both ends of the acid scraping plate 62 are fixedly connected to the sliding sleeve 63. The sliding sleeve 63 and the fixed column 61 are slidably connected. A limiting plate 65 is provided on the outside of the fixed column 61, and a first spring 64 is provided on the outside of the fixed column 61. The first spring 64 is located between the limiting plate 65 and the sliding sleeve 63. The strip steel passes through the acid scraping plate 62, and the first spring 64 provides elastic support for the sliding sleeve 63, so that the acid scraping plate 62 is in close contact with the strip steel, thereby scraping off the acid liquid on the strip steel.

[0053] The pickling tank 5 includes a pickling box 51 and guide rollers 52. The pickling box 51 is located on one side of the upper support platform 1. An acid inlet pipe and an acid outlet pipe are respectively provided on one side of the pickling box 51. Several guide rollers 52 are provided inside the pickling box 51. The guide rollers 52 guide the strip steel into the pickling box 51, where the strip steel is soaked and initially pickled, and the loose oxide scale on the surface is cleaned off.

[0054] Example 2:

[0055] The difference from Example 1 is:

[0056] A process for improving the pickling quality of hot-rolled ferritic stainless steel coils includes the following steps:

[0057] Step 1) Uncoiling and Welding: The stainless steel hot-rolled coil is fed into the uncoiling machine for uncoiling, and the two stainless steel hot-rolled coils are butt-welded together and fixed by the welding device.

[0058] Step 2) Annealing: The stainless steel strip is annealed and cooled using an annealing device;

[0059] Step 3) Descaling and shot blasting: The stainless steel strip after annealing and cooling is subjected to descaling and shot blasting operations using a descaling device and a shot blasting device to remove the oxide scale on the strip.

[0060] Step 4) Mixed acid pickling: Immerse the strip steel in a mixed acid solution with a flow acid concentration of 98 g / L and a nitric acid concentration of 87 g / L for pickling. The concentration of metal ions in the acid solution is 30 g / L. The pickling temperature is 50℃ and the pickling time is 35 minutes.

[0061] Step 5) Brushing and pickling: A mixed acid solution with a flow acid concentration of 88g / L, a nitric acid concentration of 89g / L, an acid solution metal ion concentration of 26g / L, and a pickling temperature of 45℃ is fed to the strip surface at intervals through the pickling device. At the same time, a circular brush pickles the strip surface in the acid solution intervals. The circular brush rotates at a speed of 650rpm and the brushing time is 36 minutes.

[0062] Step 6) Rinsing: Rinse the surface of the strip steel with acid by spraying water;

[0063] Step 7) Drying: Dry the stainless steel strip surface by using a drying mechanism to remove residual water stains.

[0064] Example 3:

[0065] The difference from Example 1 is:

[0066] A process for improving the pickling quality of hot-rolled ferritic stainless steel coils includes the following steps:

[0067] Step 1) Uncoiling and Welding: The stainless steel hot-rolled coil is fed into the uncoiling machine for uncoiling, and the two stainless steel hot-rolled coils are butt-welded together and fixed by the welding device.

[0068] Step 2) Annealing: The stainless steel strip is annealed and cooled using an annealing device;

[0069] Step 3) Descaling and shot blasting: The stainless steel strip after annealing and cooling is subjected to descaling and shot blasting operations using a descaling device and a shot blasting device to remove the oxide scale on the strip.

[0070] Step 4) Mixed acid pickling: Immerse the strip steel in a mixed acid solution with a flow acid concentration of 113 g / L and a nitric acid concentration of 104 g / L for pickling. The concentration of metal ions in the acid solution is 34 g / L. The pickling temperature is 53℃ and the pickling time is 39 minutes.

[0071] Step 5) Brushing and pickling: A mixed acid solution with a flow acid concentration of 96 g / L, a nitric acid concentration of 92 g / L, an acid solution metal ion concentration of 28 g / L, and a pickling temperature of 48°C is fed to the strip surface at intervals through the pickling device. At the same time, a circular brush pickles the strip surface in the acid solution intervals. The circular brush rotates at a speed of 750 rpm and the brushing time is 40 minutes.

[0072] Step 6) Rinsing: Rinse the surface of the strip steel with acid by spraying water;

[0073] Step 7) Drying: Dry the stainless steel strip surface by using a drying mechanism to remove residual water stains.

[0074] Mechanical properties of the above embodiments were tested according to GB / 4237-2015, and the test results are shown in the table below:

[0075] The appearance quality inspection results of the plates according to the above standards are as follows: Surface inspection results of Examples 1, 2, and 3: The plate surface is clean and free from obvious scratches, indentations, pits, and other defects; there are no cracks or peeling on the surface; at the same time, the surface quality of the rolled stainless steel is good, the plate shape is square, and the edges are neat without curling.

[0076] The test results showed that the mechanical properties all met the test standards of GB / 4237-2015, and the acid concentration was significantly reduced, resulting in a substantial decrease in the amount of acid used.

[0077] A process for improving the surface pickling quality of hot-rolled ferritic stainless steel coils, including a pickling device, operates as follows:

[0078] The guide rollers guide the strip steel into the pickling tank for initial pickling and cleaning off loose oxide scale on the surface. The strip steel then passes through a scraping mechanism to remove the acid, while the pinch rollers provide power for its movement. The strip steel then passes through a brushing mechanism on the upper support platform to remove the oxide scale and pickle it. After passing through the scraping mechanism again to remove the acid, the strip steel then passes through a brushing mechanism on the lower support platform to remove the oxide scale on the other side.

[0079] The process of cleaning oxidized skin is as follows:

[0080] The second motor drives the rotating column to rotate on the connecting plate through the gearbox, which in turn drives the hollow frame, sliding frame, adjusting arm, adjusting plate, moving plate, rotating plate, and round brush to rotate. At the same time, the third motor drives the rotating shaft, rotating plate, and round brush to rotate through the chain wheel and chain. The round brush then rotates while rotating to remove the oxide scale from the surface of the strip steel.

[0081] Acid is supplied to the inside of the fixed box and rotating box through the acid supply pipe and connecting box. Acid is then supplied to the acid supply branch pipe through the connecting hose and pipe fitting. When the adjusting plate rotates with the rotating column, the adjusting plate drives the outer sleeve and acid supply branch pipe to rotate via the insert rod. The acid supply branch pipe drives the connecting plate, connecting shaft, connecting frame, moving block, and follower frame to rotate. The follower frame rotates on the connecting plate, and simultaneously the connecting shaft rotates on the connecting frame. The connecting shaft and connecting plate then react with the acid supply branch pipe, causing it to rotate inside the outer sleeve while keeping the acid flow hole vertically downward. When the acid flow hole aligns with the pipe opening, acid flows through the flow hole to the strip steel. Due to the interval between the acid supply branch pipes, there is a certain interval between the acid flows from the sulfuric acid hole to the strip steel, allowing time for the acid to react with the oxide scale. After a period of reaction, the next wave of acid flushes away the previous acid and replaces it. The system uses a new acid solution to improve pickling effectiveness and reduce acid consumption. It works in conjunction with a circular brush to scrub the acid and oxide scale, promoting contact between them and enhancing pickling efficiency. When the distance between the adjusting plate and the hollow frame changes, the insert slides adaptively within the square hole, causing the outer sleeve to move accordingly. This movement, adjusted by the adjusting plate, drives the acid supply branch pipes, connecting plate, and connecting shaft, allowing the connecting frame to slide adaptively on the moving block. Therefore, adjusting the spacing between the circular brushes adjusts the spacing between the acid supply branch pipes as well as the spacing between the circular brushes on different moving plates, based on the amount of oxide scale on the strip surface. This adjusts the time interval for acid flow to the strip and the time interval for brushing the strip, thereby adjusting the intensity of brushing and pickling.

[0082] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A process for improving the pickling quality of the surface of a hot-rolled coil of ferritic stainless steel, characterized in that, Step 1) unwinding and welding: the stainless steel hot-rolled coil is sent to the uncoiler for unwinding, and the first and last ends of two stainless steel hot-rolled coils are butt-welded and fixed by the welding device; Step 2) annealing: the stainless steel strip is annealed and cooled by the annealing device; Step 3) scale breaking and shot blasting: the annealed and cooled stainless steel strip is subjected to scale breaking and shot blasting by the scale breaking device and the shot blasting device to remove the oxide scale on the strip; Step 4) mixed acid pickling: the strip is immersed in a mixed acid solution with a flow acid concentration of 80-120g / L and a nitric acid concentration of 90-110g / L for pickling, the acid metal ion concentration is 25-35g / L, the pickling temperature is 45-55℃, and the pickling time is 30-40 minutes; Step 5) brushing pickling: the mixed acid solution with a flow acid concentration of 70-100g / L, a nitric acid concentration of 80-100g / L, an acid metal ion concentration of 20-30g / L, and a pickling temperature of 40-50℃ is intermittently sent to the surface of the strip by the pickling device, and at the same time, the circular brush rotates in the acid solution to pickling the surface of the strip, the circular brush rotates at a speed of 500-800rpm, and the brushing time is 30-40 minutes; Step 6) rinsing: the acid solution on the surface of the strip is rinsed by water spraying; Step 7) drying: the residual water stains on the surface of the stainless steel strip are dried by the drying mechanism; The pickling device in step 5) includes an upper support table, a lower support table, support columns, pinch rollers, a pickling tank, an acid scraping mechanism, and a brushing mechanism, the upper support table and the lower support table are connected by a plurality of support columns, the support columns are provided with pinch rollers, one side of the upper support table is provided with a pickling tank, one side of the pickling tank is provided with a brushing mechanism, one side of the pickling tank and the brushing mechanism is provided with an acid scraping mechanism, and one side of the lower support table is provided with another set of brushing mechanism, one side of the brushing mechanism is provided with an acid scraping mechanism. The brush washing mechanism comprises sliding boxes, supporting legs, first guide rods, first lead screws, a first motor, first supporting arms, second supporting arms, hydraulic cylinders, connecting arms, connecting discs, hollow frames, rotating columns, a second motor, sliding frames, rotating rods, fixed rods, a fourth motor, adjusting arms, an adjusting plate, rotating discs, rotating shafts, a third motor, a moving plate, soft baffles, first electric push rods, sliding rods and circular brushes.

2. The process for improving the surface pickling quality of ferritic stainless steel hot-rolled coils according to claim 1, characterized in that... A plurality of through square holes are arranged on the adjusting plate.

3. The process of claim 2, wherein the ferritic stainless steel is a 430 grade stainless steel. The brush washing mechanism further comprises an acid supply pipe, a communication box, a fixed block, a fixed box, a rotating box, a connecting hose, a pipe joint, an acid supply branch pipe, an acid flow hole, an outer sleeve, a pipe opening, a connecting plate, a connecting shaft, a connecting frame, a moving block, a follower frame, a second guide rod, a second spring, a follower ring, and a plug rod.

4. The process for improving pickling quality of hot rolled coil of ferritic stainless steel as claimed in claim 3 wherein the process is characterized by The brush washing mechanism further comprises an acid receiving pool and an acid discharge pipe.

5. The process for improving the surface pickling quality of ferritic stainless steel hot-rolled coils according to claim 1, characterized in that... The acid scraping mechanism comprises a fixed column, an acid scraping plate, a sliding sleeve, a first spring, and a limiting plate.

6. The process for improving the surface pickling quality of ferritic stainless steel hot-rolled coils according to claim 1, characterized in that... The acid washing pool comprises an acid washing box and guide rollers. The acid washing pool comprises an acid washing box and guide rollers.

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