86results about "Flexible work arrangments" patented technology

The utility model provides a vertical loop rack and a vertical loop, and belongs to the field of steel rolling production equipment, a window is arranged on the operation side of a vertical loop rack body, and a hinge door is arranged at the window, so that waste steel in the rack is convenient to clean, the accident handling time is shortened, and the production efficiency is improved; when the high-speed wire rod rolling mill works normally, the first opening and closing door and the second opening and closing door are kept in a connected state and are fixed to the vertical loop rack body, and normal production is not affected; when a steel clamping accident occurs, only the first fixing mechanism and the second fixing mechanism need to be dismantled and the connection state between the first opening and closing door and the second opening and closing door needs to be released, so that the first opening and closing door and the second opening and closing door can rotate around the joint with the vertical loop rack body through the first connecting mechanism and the second connecting mechanism respectively; therefore, opening and closing between the first opening and closing door and the second opening and closing door are achieved, accidents occurring in the vertical loop rack body can be handled conveniently, and the handling efficiency is high.

The invention discloses a novel process for realizing online softening and improving cold heading performance of SCM435 series cold heading steel, and relates to the technical field of cold heading steel processing. The invention discloses a novel process for realizing online softening and improving the cold heading performance of SCM435 series cold heading steel. According to the method, S1, steel billet continuous casting forming, S2, steel billet precise heating, S3, low-temperature rolling molding, S4, wire rod standard spinning, S5, stelmor cooling and S6, heat preservation vestibule slow cooling are carried out, the uniformity of the process performance is remarkably improved, by innovatively optimizing the spinning coefficient and the roller way speed, it is fundamentally guaranteed that the disc shape is neat, the heat dissipation conditions of all positions of the wire rod in a slow cooling vestibule are consistent, and the heat dissipation efficiency of the wire rod is improved. Therefore, uniform transformation of a whole-roll structure and a same-circle structure is achieved, the consistency of cold heading performance is greatly improved, the cracking risk in the cold heading process is effectively reduced, the technology is remarkable in energy-saving and consumption-reducing effect, rolling waste heat is fully utilized for on-line softening, the traditional off-line reheating and annealing procedure is completely omitted, and energy consumption can be saved by about 30% or above.

The utility model relates to the technical field of steel production, and provides a wire and bar roller box eccentric sleeve axial adjusting mechanism which comprises a supporting piece, an adjusting assembly and a sliding key, the supporting piece is arranged outside a roller box, the adjusting assembly comprises a connecting piece, a rotating piece and a locking piece, the connecting piece is installed in a roller box hole, the rotating piece is installed on the supporting piece, and the sliding key is arranged on the rotating piece. The rotating piece is fixedly connected with the connecting piece, the locking piece is used for locking rotation of the rotating piece, an eccentric groove is formed in the connecting piece, and one end of the sliding key is arranged in the eccentric groove. The end, close to the eccentric bushing key groove, of the sliding key is designed to be of the rectangular structure, the contact area of the sliding key and the eccentric bushing key groove is increased, abrasion of the sliding key and the eccentric bushing key groove is reduced, the service life of the sliding key and the eccentric bushing is prolonged, the overhaul frequency and the labor intensity of workers are reduced, meanwhile, the cost of spare parts is saved, and the production cost is reduced. And due to the design of the rectangular structure at the end part of the sliding key, the axial adjustment eccentricity is synchronously increased, and the axial adjustment amplitude of the roller box eccentric bushing is increased.

The present application relates to a kind of hot galvanizing production line finishing machine roll replacement reduces the method of degraded product, belong to hot galvanizing continuous production process technical field.The technical scheme is: according to the following steps to operate: step one: reduce process section one and process section two strip speed;Step two: when strip weld reaches finishing machine outlet, process section two strip speed reduces to 0 m / min;Step three: replace finishing machine work roll, and flushing is carried out to the work roll after replacement;Step four: after finishing machine work roll flushing is completed, process section two speed strip starts to run with the minimum strip running speed specified by finishing machine, tension leveler and roll coater, when finishing machine, tension leveler and roll coater start finishing, tension leveling and roll coating, process section two strip speed is gradually increased, and intermediate looper is released, until process section one and process section two restore normal production speed.The beneficial effects of the present application are: it can reduce the degraded product of strip due to not finishing when finishing machine roll replacement.

This utility model discloses a support frame base for a front guide for the pinch rolls of a high-speed wire rod mill, comprising a base plate, a connecting plate, and a top plate. By providing limiting devices on two support frames, the front guide column can be fixed by controlling the studs. Combined with the operation of the control screw, the fixing block secures the front guide column. This multi-faceted fixation ensures a robust fixation of the front guide column. Various inner diameter front guides can be designed according to the specifications of the rolled products, while maintaining a consistent shape. This ensures that the same support frame base can accommodate the installation and positioning of front guides and support frames with different inner diameters. It also solves the problem of non-standard distances between the pinch rolls and the cooling guide grooves in the water tank. Furthermore, the structure is simple and easy to assemble and disassemble, thereby reducing replacement and disassembly time, increasing production line operating rate, and reducing the workload of operators.

The invention relates to a digital hot continuous rolling loop evaluation method. The method comprises the steps that the complete control period of a loop is divided into a steady-state control stage, a loop rising control stage and a loop falling control stage; establishing evaluation parameters according to the working parameters in the process of the steady state control stage, the loop rising control stage and the loop falling control stage; setting a reasonable range and an optimal range for each evaluation parameter, and mapping each evaluation parameter into a single score through a preset scoring function; and obtaining the loop control quality standard according to all the single scores. According to the method, comprehensive digital evaluation is formed by decomposing, standardizing and scoring key parameters of the whole loop control process, objective evaluation, accurate management and control, fault early warning and continuous optimization of the loop control effect are achieved by utilizing the periodic trend of the comprehensive digital evaluation, and finally the out-of-control probability of the loop and production accidents are reduced.

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.

This invention relates to an adaptive looper cable support vehicle and a looper cable support system. The support vehicle includes a vehicle body, a support frame, and two swing frames. The support frame is equipped with two outgoing contact members for adaptive contact with the cable during its outgoing journey. Each swing frame is equipped with a state switching unit, allowing it to switch between a free state and a locked state. Each swing frame has one return contact member and one follower contact member. The two return contact members are used for adaptive contact with the cable on the locked swing frame during its return journey, while the two follower contact members are used for adaptive contact with the cable on the free swing frame. This invention utilizes the natural angle between the two cables of the looper cable in the design of the outgoing and return contact members on the support vehicle, enabling the support vehicle to automatically stop or follow the cable's movement, ensuring adaptive support position, high positioning accuracy, high operational reliability, and requiring no additional power.

The invention discloses a heating, heat preservation and slow cooling system for an air cooling line, and relates to the field of heat preservation and slow cooling of the air cooling line. The heating, heat preservation and slow cooling system for the air cooling line comprises a main support, a silking machine is arranged on the right side of the top of the main support, a coiling assembly is arranged on the main support on the left side of the silking machine, and a conveying roller way assembly is arranged on the left side of the coiling assembly; an air cooling line head roller way is arranged between the conveying roller way assembly and the coiling assembly for communication, a plurality of sets of heat preservation plates are arranged above the conveying roller way assembly, a ceramic heating unit is arranged below the heat preservation plates, a top cover is arranged above the ceramic heating unit, a plurality of sets of threading pipes are arranged above the top cover, and a plurality of sets of air coolers are communicated with the lower portion of the conveying assembly. Transfer assemblies and coil collecting stations are arranged on the front side and the rear side of the main support. Through the ceramic heating unit and the heat preservation cover, the temperature in the heat preservation cover is stably controlled within the range of 500-850 DEG C, the temperature can be accurately adjusted and controlled, the slow cooling difference problem caused by seasonal changes is solved, and the influence of environment temperature fluctuation is counteracted.

The application provides a wire coil type control method and system, relates to the technical field of a steel rolling device, and comprises the following steps: issuing a baffle control instruction through an operation interface; sending the baffle control instruction to a programmable logic controller (PLC); the programmable logic controller (PLC) comprehensively judges the baffle control instruction, field conditions, interlocking signals and limit signals, and outputs a control signal; the output control signal is applied to a baffle execution mechanism to drive the baffle to perform opening or closing actions; position feedback on the baffle execution mechanism, limit switches, running states and fault signals are fed back to the PLC in real time to form a position and state closed loop; and the PLC uploads collected baffle actual opening degrees, running states and fault information data to an upper picture. The method and system have remarkable advantages in production efficiency, cost control and safe operation.

The application discloses a method for solving the oscillation caused by the mutual interference between a torque ring and a approaching controller in loop control, which comprises the following steps: setting an angular velocity oscillation detection counter and a time counter; starting the time counter after the loop is completed; simultaneously, detecting whether the loop oscillation is generated by a detection system in real time, and when the loop oscillation is generated, the angular velocity oscillation detection counter captures the time when the loop oscillation is generated in real time and records the time; and based on the counting results of the time counter and the angular velocity oscillation detection counter, the approaching controller is disabled in time to prevent the continuous oscillation of the torque ring and the approaching controller. The method can solve the oscillation problem caused by the mutual interference between the loop torque ring and the approaching controller.

The present application relates to a kind of double loop's loop quantity synchronous control method, belong to the loop pick technology field of metal rolling.The method involves two vertical loops and loop quantity synchronous regulator, and new setting loop quantity synchronous tension roller mechanism between two vertical loops;The speed of the entry strip steel and the speed of the exit strip steel of two loops are measured in real time respectively, while the actual loop quantity of two loops is measured in real time respectively, the reference speed of the tension roller of loop quantity synchronous tension roller mechanism is set according to the average value of the entry strip steel speed and the exit strip steel, the loop quantity difference of the actual loop quantity of two loops is input into loop quantity synchronous regulator, and the output value of loop quantity synchronous regulator is obtained after amplitude limiting and taking opposite processing to obtain loop quantity synchronous correction value;With reference speed plus loop quantity synchronous correction value as the real-time given speed of the tension roller of loop quantity synchronous tension roller mechanism;So as to realize the synchronous control of the loop quantity between two vertical loops without affecting the strip tension in each loop.

This invention relates to the field of steel production technology, specifically to a production line and method for shortening the non-cooled section of high-speed wire rod under the TMCP process. The production line includes a loading platform connected to the furnace inlet via an inlet roller conveyor. The furnace outlet is connected to the roughing mill, No. 1 flying shear, intermediate mill, No. 2 flying shear, pre-finishing mill, and modular mill via an outlet roller conveyor. The modular mill outlet is sequentially connected to No. 1 pinch roll, No. 3 flying shear, and finishing mill. The finishing mill outlet is sequentially connected to No. 2 pinch roll, No. 4 flying shear, mini mill, No. 3 pinch roll, No. 4 pinch roll, front pinch roll of the wire rod feeder, and the wire rod feeder. This invention enables minimal shearing of the non-cooled section at the head of high-speed wire rod produced using the TMCP process, reducing the length of the non-cooled section from 50-60 meters to 3-10 meters.

The utility model discloses a compact high -speed rolling loop support mechanism relates to the rolling technical field of metal. A compact high -speed rolling loop support mechanism, including loop platform, the inside installation of loop platform has the loop roller subassembly, and the support replacement structure is located on loop platform, and the support replacement structure includes the installation base, the support base and four bolts, and the support base fixedly connected in the bottom of loop platform, and the both sides of installation base and support base all are fixedly connected with two fixed plates, and wherein corresponding two fixed plates are fixedly connected through two bolts, the utility model discloses setting the replaceable buffer pad on the support base, and the buffer pad can effectively alleviate the impact and friction between support mechanism and ground, and most impact force and friction force are dispersed, and the damage to support base body is reduced, and the buffer pad can be individually replaced after wearing, the support base is avoided and is overall scrapped because of partial wear, and the service life of support seat is further prolonged.

The invention discloses a wire coil diameter adjusting device and method for a silking machine, the wire coil diameter adjusting device comprises a conveying roller way and two limiting units, the conveying roller way is used for bearing and driving a coil discharged by the silking machine to move, and the two limiting units are used for limiting the motion trails of the coil on the conveying roller way along the two sides of the width direction of the conveying roller way respectively; the limiting units are used for limiting the size of a coil on the conveying roller way in the width direction of the conveying roller way, and the position of each limiting unit in the width direction of the conveying roller way can be adjusted. By arranging the limiting unit, the position of the limiting unit can be adjusted in the width direction, the coil diameter requirements of wire rods of different specifications can be rapidly met, and downstream customers do not need to adjust coils. While the cost is reduced, the requirements of downstream customers for high-efficiency, low-cost and low-waste production and customization are met, the resource utilization rate is increased, and the carbon emission is reduced.

The invention relates to the technical field of bar rolling, and discloses a tension-free rolling control method based on a loop scanner in bar rolling, which comprises the following steps: S1, setting parameters of the loop scanner and related equipment, S2, carrying out preparation work before rolling, S3, carrying out tension-free control in the rolling process, and S4, carrying out inspection and maintenance after rolling. The height of the loop is monitored in real time through the loop scanner, cascade speed control and micro-tension adjustment are combined, rolled piece size fluctuation caused by dynamic speed change between racks can be effectively eliminated, the size deviation of a finished product is controlled within a smaller range, the requirement of a high-specification bar for size precision is met, the surface quality and mechanical performance of the product are improved, and the production cost is reduced. By means of tension-free rolling, friction and extrusion between the rolled piece and a guide and guard device and between the rolled piece and a roller bed are reduced, the generation probability of surface scratches and scabbing defects is reduced, meanwhile, stable rolling conditions are beneficial to homogenization of internal structures of the rolled piece, and the mechanical property of products is improved.

The application relates to the field of cold rolling technology and discloses a control method and a control circuit for six-stand rolling. The multi-stand rolling mill comprises a first stand, a second stand, a third stand, a fourth stand, a fifth stand and a sixth stand, a loop is arranged in front of the first stand, and an uncoiler is arranged in front of the loop. The continuous rolling method comprises the following steps: obtaining a first strip steel, normalizing and pickling the first strip steel; unwinding the first strip steel on the uncoiler; heating the first strip steel, when the first strip steel is heated to 81-99 DEG C, the first strip steel is sent to the loop; before the first strip steel passes through the loop and reaches the first stand, the first strip steel is heated, when the first strip steel is heated to 121-200 DEG C, the first strip steel is sent to the first stand to start rolling. The application realizes the continuous rolling of high-grade oriented silicon steel and high-grade non-oriented silicon steel, improves the production efficiency, improves the product quality and reduces the production cost.

The utility model discloses a water cooling structure of a silking machine, belongs to the technical field of silking machines, and aims to solve the problem that a wear-resistant ring of the silking machine is deformed due to thermal expansion. Comprising an inner arc plate, an outer arc plate, sector ring plates and side plates, the inner arc plate and the outer arc plate are arc plates with the middles protruding upwards, the inner arc plate and the outer arc plate are coaxially arranged, the front side edge of the inner arc plate and the front side edge of the outer arc plate are connected through one sector ring plate, and the rear side edge of the inner arc plate and the rear side edge of the outer arc plate are connected through the other sector ring plate; the inner arc plate, the outer arc plate and the two sector ring plates define an arc-shaped cooling flow channel, the two side plates seal the two ends of the cooling flow channel respectively, a water inlet pipe is arranged in the middle of the outer arc plate, water outlet pipes are arranged on the two side plates, and the outer surface of the inner arc plate is attached to the upper side surface of a wear-resistant ring of the silking machine protection cover in a matched mode. And the wear-resistant ring is cooled by cooling water, so that the hidden danger of deformation of the wear-resistant ring is eliminated. The device is simple in structure, low in investment, quick in effect and capable of reliably solving problems.

The present application relates to a kind of wire coil automatic adjusting device, including wire feeder, cooling channel, scanning detection device and multiple groups of hydraulic cylinder, runner and connecting rod and other components, the shape quality of coil is monitored in real time by scanning detection device, and is driven by hydraulic cylinder to arc plate and cover plate, and the shaping adjustment of coil is carried out, ensure that coil keeps ideal shape in cooling channel, avoid quality problem in production process.This device automatically adjusts the shape of coil, improves production efficiency and reduces the risk of manual operation, solves the irregular phenomenon of coil caused by problems such as speed mismatch, mechanical failure or temperature unevenness.

The application discloses a kind of control method and device of loop, the control method is by obtaining the preset speed limiting value of target loop, when receiving the node signal that current strip enters rolling mill, it is explained that the change of the steel coil that rolling mill is rolled on endless rolling production line is occurred, the loop speed adjustment amount of current strip is determined, according to preset speed limiting value and loop speed adjustment amount, the cascade speed interval of target loop is obtained, when rolling current strip, the running speed of target loop is controlled in cascade speed interval, to prevent the running speed of target loop reaches preset speed limiting value and cannot be adjusted, and then improve the reliability of loop control on strip production line.

The utility model discloses a pinch roll outlet guide and guard device. The device comprises a first pipe clamp and a second pipe clamp which are oppositely arranged, a first containing groove is formed in the first pipe clamp, a second containing groove is formed in the second pipe clamp, a containing cavity is defined by the first containing groove and the second containing groove, and a guide pipe for a rolled piece to penetrate through is arranged in the containing cavity. The first pipe clamp is provided with a water inlet and a water outlet which are used for being connected with an external water cooling device. The first pipe clamp is provided with the water inlet and the water outlet, so that an external water cooling device can be connected to cool the guide pipe and a rolled piece, the wear resistance of the guide pipe is improved, the service life of the pinch roll outlet guide and guard device is prolonged, the shutdown frequency is reduced, and the production cost is reduced.

The invention provides a method for detecting and judging oscillation of a hot continuous rolling finish rolling loop, and relates to the technical field of industrial automation. According to the method, after loop height closed-loop control is input, a loop angle signal of each scanning period is detected in real time, the loop angle change over-limit times and loop angle change over-limit sampling time are initialized, and a time integrator starts timing; calculating the loop angle variation of adjacent scanning periods, counting the over-limit times N of the loop angle variation according to whether the rising edge signal exceeds the angle variation threshold value, and judging oscillation according to whether the N exceeds the oscillation times judgment threshold value; and when the timer reaches the sampling period, the sampling timer is reset to start timing again. According to the method, the oscillation of the loop is judged by detecting the frequency of the actual angle variation of the loop exceeding the set threshold value in real time, the oscillation can be quickly identified in the production process, a basis is provided for adjusting PID parameters, checking mechanical equipment or optimizing a speed system, and the risk of scrap steel and equipment damage is reduced.

The application discloses a rolling method of a single-stand two-connected rolling mill for metal extremely thin strips, which is completed through a rolling mill mechanical device and a rolling mill control system, and the rolling mill mechanical device comprises, in sequence along a rolling direction of a rolled piece, a winding drum one, a deflector roll one, a thickness gauge one, a housing, a deflector roll four, a loop device, a deflector roll three, a thickness gauge three, the housing, a thickness gauge two, a deflector roll two and a winding drum two, wherein the winding drum one and the winding drum two are located on the same side of the housing. The application takes the speed difference of the rolled piece entering and leaving the loop device, the accumulated length of the loop and the position of the moving loop frame as control signals, controls the linear speed of the fast and slow speed work rolls, matches the flow of the rolled piece at the upper and lower roll gaps, prevents the continuous accumulation or reduction of the rolled piece between the two roll gaps, and realizes stable rolling and target thickness reduction.

The application discloses a cold-rolled strip steel threading method and belongs to the technical field of steel rolling process control. The method comprises the following steps: obtaining the thickness of the strip steel; when the thickness of the strip steel is greater than a set thickness, adjusting the inlet tension of a rolling mill and the rolling force, the work roll bending degree and the intermediate roll bending degree of F1, F2 and F3 racks to set values; and adjusting the strip head of the strip steel to thread through the F1, F2 and F3 racks in turn by point adjustment, so that the thickness of the strip head is reduced to the set thickness under the action of the rolling force of each rack; and adjusting the strip head to thread through the F4 and F5 racks of the rolling mill and the outlet pinch roll in turn by point adjustment until the strip head enters a coiler, the coiling tension is established after the strip steel is coiled for three turns, and the threading is completed. The method can reduce the thickness of the strip head of the strip steel to the set thickness under the action of the rolling force of each rack, ensure that the inner ring of the strip steel can form effective frictional force with the core shaft of the coiler after the strip steel is coiled by the coiler, smooth force tension is established, normal production of the rolling mill is ensured, and downtime is reduced.

The invention provides a production process of coiled screws with obvious yield plateau performance, and relates to the professional technical field of metal calendaring. According to the production process, continuous casting square billets are used as raw materials, coiled screws with different specifications are produced by controlling and adjusting the size of a high-speed wire rod rolling mill, and the coiled screws with the obvious yield plateau performance are produced by controlling the heating temperature, the rolling temperature and the spinning temperature. And the cooling control temperature of the Stelmor cooling control roller way is controlled, so that an obvious yield platform is ensured when the coiled screw product is subjected to tensile property inspection.

According to the method for improving the bar loop connection channel, a sectional type combined structure and a modular wear-resistant lining plate are introduced to achieve convenient replacement of key components and cost saving, and the high-temperature impact resistance and the service life of a guide groove, especially a horn mouth area are greatly improved and prolonged by adopting a composite wear-resistant material and optimizing a cooling system. A hydraulic precision adjusting mechanism and laser calibration are integrated to ensure the installation precision and the long-term stability of a rolling line, meanwhile, an intelligent temperature and online abrasion monitoring system is arranged to achieve conversion from passive maintenance to preventive maintenance, and finally the purposes of prolonging the service life of equipment, reducing the maintenance cost, improving the production safety and stability and promoting maintenance intelligence are achieved.

A cold rolling line, a steel sheet production line, a cold rolling method, and a steel sheet production method can suppress work roll deformation and brittle cracking during rolling. The cold rolling line includes one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit that controls a height difference of the rollers. The control unit controls the rollers so that the metal steel strip is at a lower position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most upstream mill provided farthest upstream.

This application provides a tension control compensation method, device, and storage medium for a looper mechanism, relating to the field of looper mechanism tension control technology. The method includes: acquiring production parameters of the looper mechanism during strip rolling; calculating the actual speed deviation value of the looper carriage in the looper mechanism based on the production parameters; calculating the elastic stress of the strip in the looper mechanism based on the actual speed deviation value; and compensating the tension of the looper mechanism based on the elastic stress. The technical solution of this application first confirms the actual speed deviation value of the looper mechanism using the production parameters of the looper mechanism during strip rolling, then confirms the elastic stress of the strip using the actual speed deviation value, and finally uses the elastic stress to compensate for the tension control of the looper mechanism.

The application discloses a hot continuous rolling method and device for a strip head, relates to the technical field of hot continuous rolling, and can improve the rolling stability of the strip head. The hot continuous rolling method for the strip head comprises the following steps: based on a set building-up angle, a loop is arranged between two adjacent groups of rolling rolls, in the operation direction of the strip, the connecting line between the nth loop and the nth group of rolling rolls is a first connecting line, the connecting line between the nth group of rolling rolls and the nth+1 group of rolling rolls in the operation direction of the strip is a second connecting line, and the building-up angle is the included angle between the first connecting line and the second connecting line, wherein n is a natural number greater than zero; based on the thickness variation of the head of the strip, the roll gap spacing of the rolling roll is adjusted; the loop tension after the roll gap spacing is adjusted is obtained, the position of the loop is adjusted based on the loop tension; and based on the position of the loop, the roll gap opening and closing state of the nth+1 group of rolling rolls is controlled.

The utility model belongs to the technical field of silking machines, and particularly relates to a silking machine protection cover cooling mechanism which comprises two cooling assemblies which are arranged on an upper protection cover and a lower protection cover respectively, each cooling assembly comprises a cooling pipe fixedly connected to the upper protection cover / the lower protection cover, and an opening of each cooling pipe faces the outer side wall of the upper protection cover / the lower protection cover. A first turbulent flow piece and a second turbulent flow piece are arranged in the cooling pipe, and the first turbulent flow piece and the second turbulent flow piece are arranged in the length direction of the cooling pipe. The cooling pipe is arranged on the outer side wall of the upper protective cover / the lower protective cover, cold water flows in the cooling pipe, cooling of the upper protective cover / the lower protective cover is achieved, deformation caused by local heating of the protective cover is avoided, meanwhile, the first turbulent flow piece and the second turbulent flow piece are arranged in the cooling pipe, and the cooling effect is good. And disturbance of cold water is achieved through the first turbulent flow piece and the second turbulent flow piece, laminar flow is avoided, and the cooling effect on the upper protective cover or the lower protective cover is further enhanced.