A hot-rolled stainless steel annealing and pickling line

Abstract

The present application relates to a kind of hot-rolled stainless steel annealing pickling line, including uncoiler, welding machine, deviation rectifying roller, loop, annealing furnace, pickling unit and coiler in turn along the strip running direction, and multiple groups of tension roller group and steering roller are distributed in the line, and heating device is arranged at least one of welding machine outlet, the outlet side of deviation rectifying roller, the inlet side of at least part of steering roller and the inlet side of at least part of tension roller group, to heat the strip at corresponding position to above hard brittle point temperature.The present application avoids hard brittle point temperature of strip by arranging heating device in the line and carries out fast reheat to the strip at corresponding position, especially avoids that strip is welded at hard brittle point temperature, strip steering, tension, coiling and the like, can effectively avoid weld tear, strip edge crack or strip breakage and the like, can realize high-grade strip high-speed stable operation, solve the problem that existing unit cannot normally continuous production in low temperature environment.

Description

Technical Field

[0001] This invention relates to a hot-rolled stainless steel annealing and pickling line. Background Technology

[0002] In recent years, in order to reduce processing costs, increase output and quality, improve energy efficiency, and protect the environment, stainless steel strip manufacturers have adopted advanced annealing and pickling technologies and equipment. Currently, during operation, hot-rolled annealing and pickling lines are prone to weld tearing, strip edge cracking, or strip breakage in low-temperature environments such as winter. These issues are particularly common in the production of high-grade strips such as ferrosilicon aluminum stainless steel strips and martensitic stainless steel strips. Summary of the Invention

[0003] This invention relates to a hot-rolled stainless steel annealing and pickling line, which can at least solve some of the defects of the prior art.

[0004] This invention relates to a hot-rolled stainless steel annealing and pickling line, comprising an uncoiler, a welding machine, a straightening roller, a looper, an annealing furnace, a pickling unit, and a coiler arranged sequentially along the strip running direction. The production line also includes multiple sets of tension rollers and guide rollers. A heating device is provided at least at one of the following locations: the welder outlet, the outlet side of the straightening roller, the inlet side of at least some of the guide rollers, and the inlet side of at least some of the tension roller sets, to heat the strip at the corresponding location to above the hard brittle point temperature.

[0005] As one embodiment, a first tension roller group and a first steering roller are arranged sequentially between the correction roller and the looper. The looper is equipped with at least one set of looper steering rollers. A second steering roller is arranged between the looper and the annealing furnace. A second tension roller group and a third tension roller group are arranged sequentially between the pickling unit and the coiler. The heating device is arranged at the welding machine outlet, the outlet side of the correction roller, between the first tension roller group and the first steering roller, the inlet side of each looper steering roller, the inlet side of the second steering roller, the inlet side of the second tension roller group, and the inlet side of the third tension roller group.

[0006] As one embodiment, the heating device is an electromagnetic induction heating device.

[0007] As one embodiment, at least part of the heating device includes an induction heater, which employs a closed-loop induction coil and forms a strip running channel within the coil. The induction heater is equipped with a translation drive mechanism to have a working position and an offline position.

[0008] As one implementation method, an emergency shear is arranged on the working position inlet side or the working position outlet side of the induction heater.

[0009] As one of the embodiments, a roller frame is arranged at the entrance side and the exit side of the working position respectively, and a supporting roller for supporting the strip steel is arranged on the roller frame, and the roller frame is directly integrated with the emergency shear.

[0010] As one of the embodiments, the electromagnetic induction heating device at the exit of the welding machine and the electromagnetic induction heating device at the exit of the pickling unit are both transverse magnetic induction heating devices.

[0011] As one of the embodiments, when the heating device is arranged at the exit of the welding machine, the heating device is provided with an annealing driving unit and a lifting driving unit, and the driving direction of the annealing driving unit is parallel to the width direction of the strip steel.

[0012] As one of the embodiments, each of the heating devices is provided with a protection mechanism, the protection mechanism includes a roller frame arranged on both sides of the heating device along the running direction of the strip steel, a supporting roller for supporting the strip steel is arranged on the roller frame, and a pressing roller is arranged directly above the supporting roller, and the pressing roller is provided with a pressing roller lifting driving structure.

[0013] As one of the embodiments, an infrared temperature measuring instrument is arranged at the entrance and the exit of each of the heating devices.

[0014] The present application has at least the following beneficial effects:

[0015] The annealing and pickling line for hot-rolled stainless steel provided by the present application can quickly supplement heat to the strip steel at the corresponding position in the production line by arranging the heating device, so as to heat the strip steel to above the hard brittle point temperature of the strip steel, especially to avoid the strip steel annealing, strip steel turning, tensioning, coiling and the like at the hard brittle point temperature, so as to effectively avoid the tearing of the weld, the edge cracking of the strip steel or the strip breaking and the like, and can realize the high-grade strip steel high-speed stable operation, and solve the problem that the existing unit cannot normally and continuously produce in a low temperature environment. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without any creative labor.

[0017] Figure 1 The production line process schematic diagram of the annealing and pickling line for hot-rolled stainless steel provided by the present application is shown in the following figure.

[0018] Figure 2 The structure schematic diagram of the heating device provided by the present application is shown in the following figure.

[0019] Figure 3A schematic diagram of a translation arrangement of an induction heating device provided by an embodiment of the present application is shown in FIG. 1.

[0020] Figure 4 A schematic diagram of a system composition of an induction heating device provided by an embodiment of the present application is shown in FIG. 2. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative work fall within the protection scope of the present application.

[0022] As Figure 1 , the present application provides a hot-rolled stainless steel annealing and pickling line, which comprises, in sequence along the running direction of the strip, an uncoiler 1, a welding machine 2, a deviation rectifying roller 3, a loop 9, an annealing furnace 4, a pickling unit 5, and a coiler 15, and multiple sets of tension roller groups and turning rollers are distributed in the line. The composition and layout of the above pickling line are conventional in the art, and the specific structure will not be described here. In one embodiment, as Figure 1 , a first tension roller group 7 and a first turning roller 8 are arranged in sequence between the deviation rectifying roller 3 and the loop 9, the loop 9 is provided with at least one set of loop turning rollers 91, a second turning roller 10 is arranged between the loop 9 and the annealing furnace 4, and a second tension roller group 13 and a third tension roller group 14 are arranged in sequence between the pickling unit 5 and the coiler 15. Further optionally, a fourth tension roller group 11 is arranged at the inlet side of the annealing furnace 4, and turning rollers and tension roller groups can be arranged between the annealing furnace 4 and the pickling unit 5 according to the specific site conditions, and a pre-coiling loop 12 can be selectively arranged between the second tension roller group 13 and the third tension roller group 14.

[0023] Preferably, at least one of the outlet of the welder 2, the outlet side of the rectifying roller 3, the inlet side of at least part of the diverting roller, and the inlet side of at least part of the tension roller group is provided with a heating device 6 to heat the strip at the corresponding position to above the brittle point temperature. Further preferably, the outlet of the welder 2, the outlet side of the rectifying roller 3, between the first tension roller group 7 and the first diverting roller 8, the inlet side of each loop diverting roller 91, the inlet side of the second diverting roller 10, the inlet side of the second tension roller group 13, and the inlet side of the third tension roller group 14 are all provided with the heating device 6. Among them, the heating device 6 at the inlet side of the second tension roller group 13 is preferably arranged at the outlet side of the pickling unit 5, so that the strip can be quickly heated at the pickling outlet (in this embodiment, the strip temperature is quickly raised from about 40°C to about 90°C); the heating device 6 at the outlet side of the rectifying roller 3 is preferably arranged near the outlet of the rectifying roller 3; the loop diverting roller 91 can have multiple groups, and the heating device 6 at the inlet side of the loop diverting roller 91 is preferably arranged near the inlet of the loop diverting roller 91; the heating device 6 at the inlet side of the second diverting roller 10 is preferably arranged near the inlet of the second diverting roller 10; and the heating device 6 at the inlet side of the third tension roller group 14 is preferably arranged near the inlet of the third tension roller group 14. In one of the embodiments, the distance between the heating device 6 arranged near each functional roller and the corresponding functional roller is within the range of 1-3 m.

[0024] The heating device 6 arranged at the outlet of the welding machine 2 is used for annealing heating of the weld; in the embodiment, only the martensitic special stainless steel is subjected to weld annealing treatment, and then the heating device 6 arranged at the outlet of the welding machine 2 is optionally provided with an annealing driving unit and a lifting driving unit, and the driving direction of the annealing driving unit is parallel to the width direction of the strip at the position. It can be understood that the annealing driving unit and the lifting driving unit are combined into a two-dimensional driving mechanism; in one of the embodiments, the heating device 6 is installed at the output end of the annealing driving unit, and the annealing driving unit is installed at the output end of the lifting driving unit. The above-mentioned annealing driving unit is used for moving the heating device 6 along the length direction of the weld to anneal the weld, and a conventional translation driving device can be used; the above-mentioned lifting driving unit can switch the heating device 6 between the online state and the offline state, and a conventional lifting driving device can be used, and the specific structure is not described here. After receiving the online instruction signal, the lifting driving unit starts to lift the heating device 6 to the “ready-to-work position”, and transmits the work position signal to the production line control system; when the photoelectric switch at the inlet and outlet of the heating device 6 detects the strip signal, and the heating device 6 online signal and the strip in the furnace signal both meet the conditions, the “normal positioning signal” is transmitted to the unit production line, and the heating device 6 enters the normal positioning state; in the online state of the heating device 6, the heating device 6 is opened according to the related commissioning instruction of the production line, and the heating device 6 is driven by the annealing driving unit to move at a horizontal moving speed of 3-5 m / min to uniformly anneal the weld; when the photoelectric switch at the inlet and outlet of the heating device 6 does not detect the strip signal, the heating device 6 displays the offline state and automatically stops loading, and the annealing driving unit drives the heating device 6 to move back to the “ready-to-work position” of the heating device 6 at a horizontal moving speed of 3-5 m / min, and then the lifting driving unit starts to lower the heating device 6 to the original position, and waits for the next weld annealing.

[0025] The annealing and pickling line for hot-rolled stainless steel provided in the embodiment can heat the strip at the corresponding position to above the hard and brittle point temperature of the strip through the arrangement of the heating device 6 in the production line, especially to avoid weld annealing, strip turning, tensioning, coiling and the like at the hard and brittle point temperature of the strip, so that the weld tearing, strip edge cracking or strip breaking and the like can be effectively avoided, high-grade strip can be stably operated at high speed, and the problem that the existing unit cannot normally and continuously produce in a low temperature environment can be solved.

[0026] The embodiment is especially suitable for the production of HAPL unit ferritic-aluminum stainless steel and martensitic stainless steel with a thickness specification of 2-6 mm and a width specification of 800-1600 mm, and can ensure the high-speed continuous production of these high-grade strips.

[0027] In a preferred embodiment, the heating device 6 is an electromagnetic induction heating device 6, which has a faster heating speed and a better heating effect.

[0028] In one embodiment, at least part of the heating device 6 comprises an induction heater 61, which adopts a closed-loop induction coil and forms a strip running channel within the loop of the closed-loop induction coil, and is configured with a translation driving mechanism to have an online position and an offline position. Different from the conventional open-loop coil induction heating mode, in this embodiment, the closed-loop induction coil is used to quickly reheat the strip, and the heating efficiency and the heating uniformity are significantly improved, and the closed-loop magnetic field is realized by using the copper shielding at the inlet and outlet sides and the aluminum shielding around the inductor, and the operation safety is high. Based on the movable design scheme of the induction heater 61, the working flexibility and applicability of the heating device 6 can be effectively improved; for example, for high-grade products with high added value, the induction heater 61 can be moved to the online state by the translation driving mechanism to produce fast reheat, and in particular, the high-grade strip can be heated to above the hard and brittle point temperature, realizing high-speed stable operation of high-grade strip, and completely solving the bottleneck of low-temperature environment of high-grade strip for high-speed continuous and stable production; for conventional steel products that do not need fast reheat, the induction heater 61 can be moved to the offline state to reduce production cost and avoid collision risk of the induction heater 61 caused by conventional steel over-speed operation and plate shape.

[0029] Generally, the induction heater 61 is configured with a tank circuit cabinet 62, which forms a resonance system with the induction heater 61; as a preferred embodiment, the tank circuit cabinet 62 is arranged on the top of the induction heater 61, which can simplify the equipment layout of the heating device 6, on the one hand, reducing the floor area occupied by the device, and on the other hand, in the case that the induction heater 61 is designed to be movable, the tank circuit cabinet 62 moves with the induction heater 61 according to the above cabinet design scheme, ensuring the connection reliability between the two, thereby ensuring the stability and reliability of the induction heating work.

[0030] Generally, as Figure 4 the induction heater 61 is configured with a power supply unit 69. Optionally, the power supply unit 69 comprises a incoming line rectifier cabinet and an inverter cabinet, after the three-phase current is rectified by the rectifier and filtered by the filter, it becomes smooth direct current and is sent to the inverter, and the inverter converts the direct current into higher frequency alternating current to supply the above-mentioned resonance system. Preferably, the incoming line rectifier cabinet and the inverter cabinet are designed and arranged in the cabinet, and are arranged on the side of the unit transmission. As Figure 3 For the connection between the induction heater 61 and the power supply unit 69, the connection cable between the two can be wired in the drag chain 68.

[0031] In an optional embodiment, as Figure 3The translation driving mechanism includes a translation track 67, and the induction heater 61 is slidingly arranged on the translation track 67. The translation of the induction heater 61 can be achieved by motor driving or cylinder pushing and pulling driving. Further, an online position detection device and an offline position detection device (for example, a photoelectric switch) can be arranged beside the translation track 67 to ensure the accuracy of the state of the induction heater 61.

[0032] Based on the structure of the closed-loop induction coil, the induction heater 61 cannot be directly moved out of the production line in the online state of the strip steel. In the accident state (for example, the induction heater 61 fails) or the strip steel does not need to be heated (at this time, the induction heater 61 occupies the space of the production line, and the area cannot be reasonably used for auxiliary production such as cutting and taking materials), which is not conducive to the normal operation of the production line. In the embodiment, as Figure 2 , preferably, the working position entrance side or the working position exit side of the induction heater 61 is arranged with an accident shear 65. Through the cooperation of the accident shear 65 and the movable structure of the induction heater 61, the heating device 6 adopting the closed-loop induction coil can achieve the real-time online and offline effect of the open-loop heating device 6. The cooperation mode of the accident shear 65 and the translation driving mechanism will be described in subsequent embodiments, which is omitted here.

[0033] In one of the embodiments, as Figure 2 , the working position entrance side and the working position exit side are respectively arranged with roller racks 63, and the roller racks 63 are arranged with supporting rollers for supporting the strip steel. The strip steel is supported by the two groups of supporting rollers to define the running height of the strip steel, for example, to make the strip steel at the center height of the induction heating cavity, so as to avoid the contact or collision between the strip steel and the bottom or top of the induction heating cavity. The accident shear 65 is preferably integrated with the corresponding roller rack 63 to make the production line layout compact and reduce the number of equipment and the occupied space. In one of the embodiments, the roller rack 63 is installed on the rack of the accident shear 65, or an integral rack is adopted, and the components of the accident shear 65 and the supporting rollers are arranged on the integral rack.

[0034] In the embodiment, the accident shear 65 is preferably arranged at the working position exit side, so that the strip steel can be cut off by the accident shear 65 after being cut, and the strip steel can be withdrawn from the induction heater 61 in the form of reverse running, which is more reliable.

[0035] Specifically, when the induction heater 61 is in the working position and receives an offline instruction of the induction heater 61, the accident shear 65 is started to cut the strip steel, and no strip steel is ensured in the induction heater 61, so that the induction heater 61 is moved to the offline position. When the induction heater 61 is in the offline position and receives an online instruction of the induction heater 61, the accident shear 65 is started to cut the strip steel, and no strip steel is ensured in the working position area, so that the induction heater 61 is moved to the online position.

[0036] Further, the roller frame 63 is further provided with a pressure roller above the corresponding side of the supporting roller and is provided with a lifting driving unit; the lifting driving unit can be a linear driving device such as a pneumatic cylinder or a hydraulic cylinder. By providing the pressure roller, the supporting roller and the pressure roller can improve the running stability of the strip and constrain the strip shape, avoid the impact of the strip on the cavity of the induction heater 61, and realize reasonable conveying during the strip head and tail threading process, avoid the situation that the strip head and tail are stuck due to the head or tail lifting, etc. At the same time, considering the special working conditions such as strip breakage and reverse running, when the strip breakage, reverse running and emergency stop signals are encountered, the pressure roller is pressed down to relieve the impact of the strip on the induction heater 61.

[0037] Further preferably, an auxiliary guide plate can be arranged on one of the roller frames 63, the auxiliary guide plate is hinged to one side of the roller frame 63 close to the other roller frame 63 and is connected with a guide plate driving unit (such as a pneumatic cylinder or a hydraulic cylinder) for driving the up and down swinging of the auxiliary guide plate, when the induction heater 61 is in the working position, the auxiliary guide plate is swung down; when the induction heater 61 is in the offline position, the auxiliary guide plate can be swung up to assist in completing the strip threading and the tail running.

[0038] Optionally, as shown in FIG. 6, the roller frame 63 is provided with a guide plate 65, the guide plate 65 is hinged to one side of the roller frame 63 close to the other roller frame 63 and is connected with a guide plate driving unit (such as a pneumatic cylinder or a hydraulic cylinder) for driving the up and down swinging of the guide plate 65, when the induction heater 61 is in the working position, the guide plate 65 is swung down; when the induction heater 61 is in the offline position, the guide plate 65 can be swung up to assist in completing the strip threading and the tail running. Figure 2 A pinch roller 64 can be arranged at the inlet side of the working position of the induction heater 61 to facilitate the stable running of the strip during threading and normal production. The roller frame 63 at the inlet side of the working position can be integrated and installed on the pinch roller 64.

[0039] Optionally, as shown in FIG. 6, the roller frame 63 is provided with a guide plate 65, the guide plate 65 is hinged to one side of the roller frame 63 close to the other roller frame 63 and is connected with a guide plate driving unit (such as a pneumatic cylinder or a hydraulic cylinder) for driving the up and down swinging of the guide plate 65, when the induction heater 61 is in the working position, the guide plate 65 is swung down; when the induction heater 61 is in the offline position, the guide plate 65 can be swung up to assist in completing the strip threading and the tail running. Figure 2 A blowing device 66 can be arranged on the above-mentioned emergency cutting frame to realize protection blowing, when the reverse running, strip breakage and unit stop signals are encountered, the blowing device 66 will automatically start blowing until the unit runs normally to avoid the influence of the reverse flow of liquid on the production line on the normal operation of the induction heater 61.

[0040] Preferably, the electromagnetic induction heating device 6 for weld annealing adopts a transverse magnetic induction heating mode, the power unit 69 selects a 100khz high-frequency MOSFET power supply, the power is about 60KW, the induction heater 61 adopts a single-turn coil winding mode, and the strip weld can be rapidly heated to about 700℃; the electromagnetic induction heating device 6 at the outlet of pickling adopts a transverse magnetic induction heating mode, the power unit 69 selects a 15khz power frequency IGBT power supply, the power is about 200KW, the induction heater 61 adopts a multi-turn coil winding mode, and the strip can be rapidly heated to 90-100℃; other electromagnetic induction heating devices 6 adopt a longitudinal magnetic induction heating mode, the power unit 69 selects a 15khz power frequency IGBT power supply, the power is 200-300KW, and the induction heater 61 adopts a single-turn whole plate induction coil to rapidly heat the strip to 90-100℃.

[0041] As described in the above embodiment, each heating device 6 is provided with a protection mechanism 63, which includes roller frames 63 arranged on both sides of the heating device 6 along the running direction of the strip, and supporting rollers for supporting the strip and pressure rollers arranged directly above the supporting rollers, and the pressure rollers are provided with pressure roller lifting driving structures. Through the protection mechanism 63, the shaking of the strip during running can be controlled, the strip deviation can be suppressed, the collision of the strip with the induction heater 61 caused by the strip breaking and the strip shape can be alleviated, etc.

[0042] Further preferably, a temperature measuring instrument is arranged at the outlet of each heating device 6; the temperature measuring instrument can be an infrared temperature measuring instrument or other temperature measuring element suitable for measuring the temperature of the strip. By arranging the temperature measuring instrument at the outlet of the heating device 6, the online accurate measurement of the temperature of the strip at the outlet is realized, and thus the closed-loop control of the operation of the heating device 6 is ensured.

[0043] In another embodiment, at least part of the tension rollers and the deflection rollers in the above-mentioned hot-rolled stainless steel annealing and pickling line are heating rollers, which can be electromagnetic heating rollers or hot oil rollers; by using the heating rollers, the strip can be heated to a certain extent under the condition of meeting the basic functions of the rollers, and the above-mentioned heating device 6 can be used to achieve better heating effect and improve the production quality of the strip. In particular, if the heating rollers are used in the loop 9, the heating effect is better due to the relatively longer contact time with the strip.

[0044] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A hot-rolled stainless steel annealing and pickling line, comprising an uncoiler, a welding machine, a straightening roller, a looper, an annealing furnace, a pickling unit, and a coiler arranged sequentially along the strip running direction, and wherein multiple sets of tension rollers and guide rollers are distributed in the production line, characterized in that: A first tension roller group and a first steering roller are arranged sequentially between the straightening roller and the looper. The looper is equipped with at least one set of looper steering rollers. A second steering roller is arranged between the looper and the annealing furnace. A second tension roller group and a third tension roller group are arranged sequentially between the pickling unit and the coiler. Heating devices are arranged at the welding machine outlet, the outlet side of the straightening roller, between the first tension roller group and the first steering roller, the inlet side of each looper steering roller, the inlet side of the second steering roller, the inlet side of the second tension roller group, and the inlet side of the third tension roller group to heat the strip steel at the corresponding position to above the hard brittle point temperature. The heating device on the inlet side of the second tension roller group is arranged on the outlet side of the pickling unit to rapidly heat up the pickled strip at the outlet; the heating device on the outlet side of the straightening roller is arranged near the outlet of the straightening roller; the heating device on the inlet side of the looper guide roller is arranged near the inlet of the looper guide roller; the heating device on the inlet side of the second guide roller is arranged near the inlet of the second guide roller; and the heating device on the inlet side of the third tension roller group is arranged near the inlet of the third tension roller group. The distance between the heating device arranged near each functional roller and the corresponding functional roller is in the range of 1~3m; At least a portion of the heating device includes an induction heater, which employs a closed-loop induction coil and forms a strip running channel within the coil. The induction heater is equipped with a translation drive mechanism to have a working position and an offline position. Each of the heating devices is equipped with a protective mechanism, which includes roller frames arranged on both sides of the heating device along the running direction of the strip. The roller frames are equipped with idler rollers for supporting the strip and pressure rollers arranged directly above the idler rollers. The pressure rollers are equipped with a pressure roller lifting drive structure. The pressure rollers are used to cooperate with the idler rollers to improve the running stability of the strip and constrain the shape of the strip, prevent the strip from impacting the induction heater cavity, and achieve reasonable conveying during the strip threading process to avoid the strip from sticking or overlapping, which could cause the strip to jam. In the event of a strip breakage, reversal, or emergency stop signal, the pressure rollers press down to reduce the impact of the strip on the induction heater. An emergency shear is arranged on the inlet or outlet side of the working position of the induction heater, and the roller frame is directly integrated with the emergency shear. At least some of the tension rollers and the steering rollers are heated rollers, and the heated rollers are electromagnetic heating rollers or hot oil rollers; wherein the looper steering roller is a heated roller.

2. The hot-rolled stainless steel annealing and pickling line as described in claim 1, characterized in that: Both the electromagnetic induction heating device at the welding machine outlet and the electromagnetic induction heating device at the pickling unit outlet are transverse magnetic induction heating devices.

3. The hot-rolled stainless steel annealing and pickling line as described in claim 1, characterized in that: When a heating device is arranged at the outlet of the welding machine, the heating device is equipped with an annealing drive unit and a lifting drive unit, and the driving direction of the annealing drive unit is parallel to the width direction of the strip at that location.

4. The hot-rolled stainless steel annealing and pickling line as described in claim 1, characterized in that: Temperature measuring instruments are installed at the inlet and outlet of each of the heating devices.

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