Protective gas pipeline system for trolley-type annealing furnace and trolley-type annealing furnace

Abstract

A protective gas pipeline unit comprises an exhaust pipe fixedly installed on a coil base, the gas inlet end of the exhaust pipe is located above the coil base, the exhaust end of the exhaust pipe is located below the coil base, the gas inlet pipe comprises a straight pipe section and a bent pipe section, the straight pipe section is sleeved with the exhaust pipe, and the bent pipe section is sleeved with the exhaust pipe. The tail end of the bent pipe section is located below the furnace platform and connected with a process gas conveying pipeline, the overhauling pipe is communicated with the exhaust pipe, a discharge port of the discharge main pipe is located outside a furnace cavity of the trolley type annealing furnace, and the gas inlet end of the exhaust adjusting pipeline unit is communicated with the exhaust end of the exhaust pipe. The two exhaust ends of the exhaust adjusting pipeline unit are communicated with the exhaust main pipe and the furnace cavity respectively, the protective gas pipeline structure is simplified, impurities in the exhaust pipe are convenient to clean, it is guaranteed that the atmosphere in the cover flows and is exhausted evenly and smoothly, hydrogen in waste gas is fully utilized, emission is reduced, and energy is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of annealing of grain-oriented electrical steel, in particular to a protective gas pipeline system for a trolley-type annealing furnace and a trolley-type annealing furnace. Background Art

[0002] The trolley-type annealing furnace is mainly used for the heat treatment of large carbon steel and alloy steel parts, and mainly consists of a heating furnace body, a furnace car and a furnace car traction mechanism, a furnace door and a furnace door lifting and pressing device, heating elements and fixing devices, an electric temperature control system and other parts.

[0003] When the grain-oriented electrical steel is subjected to high-temperature annealing, the steel strip coil is placed upright on the furnace platform of the furnace car and covered with an inner cover made of heat-resistant steel, and heat treatment is carried out in the heating furnace body. Different proportions and flows of nitrogen and hydrogen need to be introduced as protective atmospheres in the heating, heat preservation, and cooling process sections. The flow of the protective atmosphere and the smooth discharge of waste gas need to be controlled according to the process temperature requirements throughout the process. The smooth flow of the protective gas inside the cover is related to the pressure change inside the cover, and the excessive pressure fluctuation affects the annealing quality of the steel coil.

[0004] At present, the protective gas pipeline generally consists of an intake pipe and 3-4 exhaust pipes corresponding to the intake pipe. Multiple exhaust pipes pass through the refractory layer of the furnace platform and are arranged around and then converge to an exhaust main pipe at the bottom of the furnace car and are led out for discharge. A ball valve is installed on the pipeline, and the opening degree of the valve is manually adjusted to control the exhaust volume. The structure of this protective gas pipeline is intricate, with many elbows and difficult to install.

[0005] With the increase in the frequency of use, during the annealing of the steel coil, waste gas drives tiny scale, sealing sand, magnesium oxide particles, etc. inside the cover into the pipeline, causing pipeline blockage, and then causing the problem of blocked air flow, which is not conducive to the gas flow in the space inside the cover and between the steel strip layers. It requires frequent manual intervention in the valve, affecting the product quality, and it is difficult to clean manually after the pipeline is blocked and cannot be thoroughly cleaned.

[0006] In addition, the waste gas discharged during the heat treatment process often contains hydrogen. Currently, the waste gas is usually directly discharged outside the furnace, wasting a part of the hydrogen energy. Summary of the Utility Model

[0007] The applicant of the present utility model aims at the above-mentioned disadvantages in the existing production technology, and provides a protective gas pipeline system for a trolley-type annealing furnace and a trolley-type annealing furnace, so as to simplify the structure of the protective gas pipeline, reduce the installation difficulty of the protective gas pipeline structure, facilitate the cleaning of impurities in the exhaust pipe, ensure the uniform and smooth flow and discharge of the atmosphere inside the cover, make full use of the hydrogen in the waste gas, reduce emissions and save energy.

[0008] The technical solution adopted by the present utility model is as follows:

[0009] A protective gas pipeline system for a trolley-type annealing furnace, including a protective gas pipeline unit, and the protective gas pipeline unit includes:

[0010] An exhaust pipe, which is fixedly installed on the furnace platform of the trolley-type annealing furnace. The intake end of the exhaust pipe is located above the furnace platform, and the exhaust end of the exhaust pipe is located below the furnace platform.

[0011] An intake pipe, which includes a straight pipe section and a bent pipe section located below the straight pipe section. The exhaust pipe is sleeved outside the straight pipe section. The head end of the bent pipe section is connected to the straight pipe section, and the tail end of the bent pipe section is located outside the exhaust pipe and is connected to a process gas delivery pipeline.

[0012] An inspection pipe, which is communicated with the exhaust pipe and is used to remove impurities in the exhaust pipe.

[0013] The protective gas pipeline system further includes a main discharge pipe and an exhaust adjustment pipeline unit.

[0014] The discharge port of the main discharge pipe is located outside the furnace cavity of the trolley-type annealing furnace.

[0015] The intake end of the exhaust adjustment pipeline unit is communicated with the exhaust end of the exhaust pipe. The exhaust end of the exhaust adjustment pipeline unit has two places, which are respectively communicated with the main discharge pipe and the furnace cavity.

[0016] As a further improvement of the above technical solution:

[0017] A protective part is installed at the intake end of the exhaust pipe, and the protective part is used to block impurities from entering the exhaust pipe.

[0018] The structure of the protective part is as follows: it includes a baffle with an annular structure. The inner edge of the baffle is connected to the outer wall of the straight pipe section. The diameter of the outer edge of the baffle is adapted to the diameter of the exhaust pipe. The outer edge of the baffle is connected to the exhaust pipe, and a plurality of ventilation holes are arranged on the baffle.

[0019] The structure of the inspection pipe includes a connecting pipe. One end of the connecting pipe is connected to the exhaust end of the exhaust pipe, and the other end of the connecting pipe is provided with a flange, and a blind plate is detachably installed on the flange.

[0020] The inspection pipe further includes an adapter pipe, and the adapter pipe communicates the connecting pipe with the exhaust end of the exhaust pipe, and at the same time makes the axis angle between the exhaust pipe and the connecting pipe less than 180 degrees.

[0021] The exhaust adjustment pipeline unit includes a shunt pipe, an internal relief pipe and an external relief pipe.

[0022] One end of the shunt pipe is communicated with one end of the inner relief pipe, the other end of the inner relief pipe is located in the furnace cavity, the other end of the shunt pipe is communicated with one end of the outer relief pipe, the other end of the outer relief pipe is communicated with the main discharge pipe, and the middle part of the shunt pipe is communicated with the exhaust pipe.

[0023] The exhaust gas regulating pipeline unit further includes a manifold pipe;

[0024] One end of the manifold pipe is communicated with the exhaust pipe, and the other end of the manifold pipe is communicated with the middle part of the shunt pipe.

[0025] An inner relief regulating valve is arranged on the inner relief pipe, and an outer relief regulating valve is arranged on the outer relief pipe.

[0026] The number of the protective gas pipeline units and the exhaust gas regulating pipeline units is multiple groups and they correspond one by one. Multiple sets of protective gas pipeline units and exhaust gas regulating pipeline units are arrayed on the furnace platform.

[0027] A trolley-type annealing furnace includes the above-mentioned protective gas pipeline system for the trolley-type annealing furnace. The trolley-type annealing furnace is used for the heat treatment of grain-oriented silicon steel coils. The trolley-type annealing furnace includes a furnace car, and the furnace platform of the furnace car is used for placing the grain-oriented silicon steel coils.

[0028] The beneficial effects of the present utility model are as follows:

[0029] The structure of the present utility model is compact and reasonable, and the operation is convenient. By adopting a sleeve structure, protective gas is provided into the inner cover at the central position and the waste gas in the inner cover is discharged. On the premise of ensuring uniform and smooth flow and discharge of the atmosphere in the inner cover, the structure of the protective gas pipeline is simplified, a large number of elbow structures and welding operation contents are avoided, and the installation difficulty of the protective gas pipeline structure is reduced; by arranging a maintenance pipe on the exhaust pipe, impurities in the exhaust pipe can be cleaned in time to ensure uniform and smooth flow and discharge of the atmosphere in the inner cover; the exhaust gas regulating pipeline unit is used to connect the exhaust pipe, the main discharge pipe and the furnace cavity, so that the hydrogen in the waste gas can be used to heat the furnace cavity, the hydrogen in the waste gas is fully utilized, and emissions are reduced and energy is saved.

[0030] The present utility model further includes the following advantages:

[0031] (1) A protective part is installed at the waste gas inlet between the straight pipe section and the exhaust pipe, which effectively prevents various impurities from entering the pipeline during the annealing of the grain-oriented silicon steel coil, makes the flow and discharge of the atmosphere in the inner cover more uniform and smooth, reduces the pressure fluctuation in the inner cover, reduces the frequency of manually adjusting the exhaust volume of the exhaust pipe, reduces the amount of personnel operation during the production process, and reduces the labor intensity.

[0032] (2) An inspection pipe is provided at the lower end of the exhaust pipe of the casing structure. By means of reverse blowing, impurities in the exhaust pipe are blown out from the exhaust gas inlet of the exhaust pipe, so that the impurities in the exhaust pipe can be cleaned regularly, ensuring the uniform and smooth flow and discharge of the atmosphere in the further hood, facilitating the adjustment of the pressure in the hood, and improving the stability of product quality.

[0033] (3) An exhaust gas regulation pipeline unit is provided in the exhaust pipe group. The exhaust path of the exhaust gas is divided into two paths through a shunt pipe connected to the exhaust pipe in the middle. One path leads to the inside of the furnace cavity, and the other path leads to the outside of the furnace cavity through the main discharge pipe. During the heating and heat preservation processes of the annealing furnace, the exhaust gas can be discharged into the furnace cavity to burn the remaining hydrogen, saving fuel. When the annealing furnace is cooling down, the exhaust gas can be discharged outside the furnace cavity without affecting the stability of the atmosphere in the hood. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic structural view of the present utility model.

[0035] Figure 2 It is a schematic view of the gas flow direction of the present utility model.

[0036] Figure 3 It is a schematic structural view of the protective gas pipeline unit and the exhaust gas regulation pipeline unit of the present utility model.

[0037] Figure 4 It is a front view of the protective gas pipeline unit of the present utility model.

[0038] Figure 5 It is a schematic structural view of the protective member of the present utility model.

[0039] Figure 6 It is a schematic view of the array distribution of the protective gas pipeline unit and the exhaust gas regulation pipeline unit of the present utility model.

[0040] Figure 7 is Figure 6 a partial enlarged view.

[0041] Wherein:

[0042] 1. Inlet pipe; 11. Straight pipe section; 12. Elbow section; 13. Interface;

[0043] 2. Exhaust pipe; 21. Inspection pipe; 211. Connecting pipe; 212. Flange; 213. Adapter pipe; 22. Protective member; 221. Baffle; 222. Vent hole;

[0044] 3. Furnace platform; 31. Refractory layer; 32. Bottom frame;

[0045] 4. Process detection pipe; 5. Temperature measuring pipe;

[0046] 6. Exhaust pipe group; 61. Confluence pipe; 62. Inner relief pipe; 621. Inner relief regulating valve; 63. Shunt pipe; 64. Main discharge pipe; 65. Outer relief pipe; 651. Outer relief regulating valve; 66. Glow heater; 7. Grain-oriented silicon steel coil; 8. Heating furnace body; 81. Furnace cavity; 9. Inner cover. Detailed implementation manners

[0047] In the embodiment of the present application, by providing a protective gas pipeline system for a trolley-type annealing furnace and a trolley-type annealing furnace, the problems in the prior art that the protective gas pipeline structure of the trolley-type annealing furnace is intricate, has many elbows, is difficult to install, is difficult to clean manually after the pipeline is blocked, and the waste gas is directly discharged outside the furnace, wasting energy are solved. By adopting a sleeve form for the intake exhaust pipe, the intake and exhaust are balanced, the number of exhaust pipes is reduced, thereby simplifying the protective gas pipeline structure, reducing the installation difficulty of the protective gas pipeline structure, arranging the maintenance pipe 21 to facilitate the cleaning of impurities in the exhaust pipe, ensuring uniform and smooth flow and discharge of the atmosphere in the cover, and arranging the exhaust adjustment pipeline unit to make full use of the hydrogen in the waste gas, reducing emissions and saving energy. The technical solutions will be described in detail below with reference to the accompanying drawings and specific implementation manners.

[0048] Embodiment 1:

[0049] As Figures 1 - 2 shown, the protective gas pipeline system for a trolley-type annealing furnace in this embodiment includes a protective gas pipeline unit, and the protective gas pipeline unit includes: an exhaust pipe 2, an intake pipe 1, and a maintenance pipe 21.

[0050] The exhaust pipe 2 is fixedly installed on the furnace platform 3 of the trolley-type annealing furnace. The intake end of the exhaust pipe 2 is located above the furnace platform 3, and the exhaust end of the exhaust pipe 2 is located below the furnace platform 3.

[0051] The intake pipe 1 includes a straight pipe section 11 and a bent pipe section 12 located below the straight pipe section 11. The exhaust pipe 2 is sleeved outside the straight pipe section 11. The head end of the bent pipe section 12 is connected to the straight pipe section 11, and the tail end of the bent pipe section 12 is located outside the exhaust pipe 2 and connected to the process gas delivery pipeline. Wherein, the middle part of the bent pipe section 12 can penetrate through the pipe wall of the exhaust pipe 2, or as Figure 4 shown, pass through from the exhaust end of the exhaust pipe 2 and penetrate through the maintenance pipe 21. The tail end of the bent pipe section 12 is located below the furnace platform 3.

[0052] The maintenance pipe 21 is communicated with the exhaust pipe 2 and is used to remove impurities in the exhaust pipe 2.

[0053] The protective gas pipeline system further includes a main discharge pipe 64 and an exhaust adjustment pipeline unit.

[0054] The discharge port of the main discharge pipe 64 is located outside the furnace cavity 81 of the trolley-type annealing furnace.

[0055] The intake end of the exhaust gas regulation pipeline unit is connected to the exhaust end of the exhaust pipe 2. The exhaust end of the exhaust gas regulation pipeline unit has two outlets, which are respectively connected to the main discharge pipe 64 and the furnace cavity 81 of the trolley-type annealing furnace. The exhaust gas regulation pipeline unit provides two flow paths for the waste gas in the exhaust pipe 2. One path flows into the furnace cavity 81 for combustion to heat the furnace cavity 81, and the other path flows into the main discharge pipe 64 to discharge from the annealing furnace.

[0056] The trolley-type annealing furnace is used for the heat treatment of the grain-oriented silicon steel coil 7. The trolley-type annealing furnace includes a furnace car. The furnace table 3 of the furnace car is used to place the grain-oriented silicon steel coil 7. The structure of the furnace table 3 includes a bottom frame 32 made of steel structure. A refractory layer 31 is built on the steel frame panel on the upper surface of the bottom frame 32. During heat treatment, the inner cover 9 covers the outside of the grain-oriented silicon steel coil 7. The intake pipe 1 and the exhaust pipe 2 are located inside the inner cover 9. The process gas delivery pipeline is connected to the elbow section 12. Process gas is delivered into the inner cover 9 through the intake pipe 1. The process gas includes nitrogen and hydrogen. The waste gas inside the inner cover 9 is discharged from the exhaust pipe 2.

[0057] As Figure 2 shown, there are columns arranged on the furnace table 3, and a bottom plate is arranged on the columns. The central hole of the bottom plate corresponds to the inner hole of the grain-oriented silicon steel coil 7. The exhaust pipe 2 is arranged vertically and forms a sleeve structure with a partial section of the intake pipe 1 and corresponds to the inner hole of the grain-oriented silicon steel coil 7. The upper end (the exhaust end of the intake pipe 1) of the straight pipe section 11 of the intake pipe 1 is above the upper end (the intake end) of the exhaust pipe 2. The upper end of the straight pipe section 11 is located at the bottom position of the grain-oriented silicon steel coil 7. The protective gas is discharged from the upper end of the straight pipe section 11 and then flows upward along the height direction of the grain-oriented silicon steel coil 7. After turning at the top of the inner cover 9, it flows downward along the side wall of the inner cover 9 and returns to the intake end of the exhaust pipe 2 through the gap between the columns, enters the exhaust pipe 2, and then is discharged from the exhaust pipe group 6. The exhaust pipe group 6 includes the main discharge pipe 64 and the exhaust gas regulation pipeline unit connected thereto.

[0058] While the diameters of the straight pipe section 11 and the exhaust pipe 2 meet the process flow requirements of the protective gas, it is ensured that the intake air volume and exhaust air volume inside the inner cover 9 can be balanced, and the pressure of the protective gas inside the cover is stabilized.

[0059] A valve is arranged on the exhaust pipe group 6, and the exhaust volume of the exhaust pipe group 6 can be adjusted by changing the opening and closing degree of the valve, so as to ensure the smooth flow of the protective atmosphere under different process intake air volumes.

[0060] By adopting a casing structure, the supply of protective gas into the inner cover 9 and the discharge of waste gas from the cover are realized at the central position. On the premise of ensuring uniform and smooth flow and discharge of the atmosphere inside the cover, the structure of the protective gas pipeline is simplified, a large number of elbow structures and welding operations are avoided, and the installation difficulty of the protective gas pipeline structure is reduced; by arranging a maintenance pipe 21 on the exhaust pipe 2, impurities in the exhaust pipe can be cleaned in time to ensure uniform and smooth flow and discharge of the atmosphere inside the cover; the exhaust adjustment pipeline unit is used to connect the exhaust pipe 2, the main discharge pipe 64 and the furnace chamber 81, so that the hydrogen in the waste gas can be used to heat the furnace chamber 81, the hydrogen in the waste gas is fully utilized, and emissions are reduced and energy is saved.

[0061] Further, as Figures 3 - 5 shown, a protective part 22 is installed at the intake end of the exhaust pipe 2, and the protective part 22 is used to block impurities from entering the exhaust pipe 2.

[0062] A protective part 22 is installed at the waste gas inlet between the straight pipe section 11 and the exhaust pipe 2, which effectively prevents various impurities from entering the pipeline during the annealing of the grain-oriented silicon steel coil 7, makes the flow and discharge of the atmosphere inside the cover more uniform and smooth, reduces the pressure fluctuation inside the cover, reduces the frequency of manually adjusting the exhaust volume of the exhaust pipe 2, reduces the amount of personnel operation during the production process, and reduces the labor intensity.

[0063] As Figure 5 shown, the structure of the protective part 22 includes a baffle 221 with an annular structure. The inner edge of the baffle 221 is connected to the outer wall of the straight pipe section 11. The diameter of the outer edge of the baffle 221 is adapted to the diameter of the exhaust pipe 2. The outer edge of the baffle 221 is connected to the exhaust pipe 2, and a plurality of ventilation holes 222 are arranged on the baffle 221.

[0064] The protective part 22 with an orifice plate structure reduces the probability of impurities entering the exhaust pipe 2 and simultaneously plays a connecting and supporting role between the straight pipe section 11 and the exhaust pipe 2; when installing the protective part 22, only the outer edge of the baffle 221 is spot-welded and fixed to the exhaust pipe 2, which is convenient for cutting and disassembly. The inner edge of the baffle 221 is sleeved outside the straight pipe section 11, and the plurality of ventilation holes 222 on the baffle 221 are evenly distributed on the annular surface of the baffle 221, and the total cross-sectional area of the ventilation holes 222 meets the flow requirements of the protective atmosphere.

[0065] Further, as Figures 3 - 7 shown, the structure of the maintenance pipe 21 includes a communicating pipe 211. One end of the communicating pipe 211 is connected to the exhaust end of the exhaust pipe 2, and a flange 212 is arranged at the other end of the communicating pipe 211. A blind plate is detachably installed on the flange 212.

[0066] As Figures 3 - 7As shown, the maintenance pipe 21 further includes a transition pipe 213. The transition pipe 213 connects the communication pipe 211 with the exhaust end of the exhaust pipe 2, and at the same time makes the axis angle between the exhaust pipe 2 and the communication pipe 211 less than 180 degrees. Specifically, the transition pipe 213 is an elbow, and the elbow angle is greater than or equal to 90 degrees, which is used to change the direction of the communication pipe 211 so that it has a different direction from that of the exhaust pipe 2, facilitating personnel operation.

[0067] The usage method of the maintenance pipe 21 in this embodiment is as follows:

[0068] According to the usage frequency and usage effect, before the trolley-type annealing furnace operates, the blind plate on the flange 212 can be disassembled, and then a compressed air pipeline with a pressure above 0.4 MPa is connected to the port of the flange 212, and compressed air is introduced into the communication pipe 211 for purging. A large amount of dust particles and scale accumulated on the inner wall of the communication pipe 211 and at the transition pipe 213 can be discharged from the exhaust gas inlet at the upper end of the exhaust pipe 2, achieving the purpose of cleaning the pipeline.

[0069] By providing the maintenance pipe 21 at the lower end of the exhaust pipe 2 with a sleeve structure and blowing air in the reverse direction, the impurities in the exhaust pipe can be blown out from the exhaust gas inlet of the exhaust pipe 2, and the impurities in the exhaust pipe 2 can be cleaned regularly, ensuring the uniform and smooth flow and discharge of the atmosphere in the hood, facilitating the adjustment of the pressure in the hood, and improving the stability of product quality.

[0070] Furthermore, as Figure 3 、 Figure 4 、 Figure 7 shown, the exhaust gas regulation pipeline unit includes a shunt pipe 63, an internal relief pipe 62, and an external relief pipe 65; one end of the shunt pipe 63 is connected to one end of the internal relief pipe 62, the other end of the internal relief pipe 62 is located inside the furnace cavity 81, the other end of the shunt pipe 63 is connected to one end of the external relief pipe 65, the other end of the external relief pipe 65 is connected to the main discharge pipe 64, and the middle part of the shunt pipe 63 is connected to the exhaust pipe 2.

[0071] Among them, the tail end of the internal relief pipe 62 is one exhaust end of the exhaust gas regulation pipeline unit, the tail end of the external relief pipe 65 is the other exhaust end of the exhaust gas regulation pipeline unit, and the intake end of the exhaust gas regulation pipeline unit is located at the middle part of the shunt pipe 63 and is connected to the exhaust pipe 2.

[0072] As Figure 3 、 Figure 4 、 Figure 7 shown, the exhaust gas regulation pipeline unit further includes a confluence pipe 61; one end of the confluence pipe 61 is connected to the exhaust pipe 2, and the other end of the confluence pipe 61 is connected to the middle part of the shunt pipe 63.

[0073] An internal relief valve 621 is provided on the internal relief pipe 62, and an external relief valve 651 is provided on the external relief pipe 65.

[0074] In addition, the air inlet of the manifold 61 is located above the adapter pipe 213 to prevent impurities in the gas from entering the manifold 61 during the purging process of the inspection pipe 21. A process detection pipe is provided on the shunt pipe 63 on one side of the internal vent pipe 62 for measuring the atmosphere dew point, and a drain port is provided on the shunt pipe 63 at the inlet of the external vent regulating valve 651 for easy maintenance and cleaning.

[0075] An exhaust adjustment pipeline unit is provided in the exhaust pipe group 6. The exhaust path of the waste gas is divided into two paths through the shunt pipe 63 connected to the exhaust pipe 2 in the middle. One path leads to the inside of the furnace chamber 81, and the other path leads to the outside of the furnace chamber 81 through the main exhaust pipe 64. During the heating-up and heat-preservation processes of the annealing furnace, the waste gas can be discharged into the furnace chamber 81 to burn the remaining hydrogen, saving fuel. When the annealing furnace is cooling down, the waste gas can be discharged outside the furnace chamber 81 without affecting the stability of the atmosphere inside the hood.

[0076] When the exhaust pipe group 6 is in use in this embodiment, the operation method is as follows:

[0077] Before the temperature in the furnace chamber 81 rises from room temperature to before introducing the protective gas, both the internal vent pipe 62 and the external vent pipe 65 in the exhaust pipe group 6 can be kept open to ensure smooth gas flow inside the hood.

[0078] After the temperature in the furnace chamber 81 rises to a certain temperature to meet the condition of introducing hydrogen, close the external vent regulating valve 651 and open the internal vent regulating valve 621. On the premise of stabilizing the pressure inside the hood, the external vent regulating valve 651 can be appropriately closed or fully closed and the internal vent regulating valve 621 can be opened wider to control the waste gas discharged into the furnace chamber 81 to participate in combustion and provide heat energy.

[0079] Introduce the process gas into the inlet pipe 1 according to the process requirements to form a protective atmosphere inside the hood. Adjust the valve openings of the external vent regulating valve 651 and the internal vent regulating valve 621 according to the pressure detection device inside the inner hood 9 to adjust the pressure inside the hood and maintain the stability of the pressure inside the hood.

[0080] In the cooling process section, under the condition that the pressure inside the hood is controllable, appropriately close or fully close the internal vent regulating valve 621 and open the external vent regulating valve 651 to control the gas inside the hood to be discharged outside the furnace chamber 81 and flow to the main exhaust pipe 64 equipped with the glow heater 66 for exhaust combustion.

[0081] Timely clean the impurities in the exhaust pipe 2 to ensure smooth exhaust of the exhaust pipe 2, which is convenient for adjusting the pressure inside the hood in each stage and improving the stability of product quality.

[0082] Embodiment 2:

[0083] Different from Embodiment 1, as Figure 6As shown, the number of the protective gas pipeline units and the exhaust gas regulating pipeline units is multiple groups and they correspond to each other one by one. Multiple sets of protective gas pipeline units and exhaust gas regulating pipeline units are arrayed on the furnace platform 3.

[0084] One set of protective gas pipeline unit and exhaust gas regulating pipeline unit corresponds to one inner cover 9.

[0085] The elbow section 12 of each group of protective gas pipeline units is arranged along the length direction of the furnace platform 3 and is fixed to the bottom frame 32 through pipe clamps. An interface 13 is arranged at the end of the elbow section 12. Multiple interfaces 13 are arranged side by side at one end of the bottom frame 32, which is convenient for centralized installation and connection of the process gas transmission pipeline.

[0086] The main discharge pipe 64 is located below the furnace platform 3, and the discharge port of the main discharge pipe 64 and the interface 13 are on the same side of the furnace platform 3.

[0087] Embodiment 3:

[0088] The trolley-type annealing furnace of this embodiment includes the protective gas pipeline system for the trolley-type annealing furnace in the above embodiment. The trolley-type annealing furnace is used for the heat treatment of the grain-oriented silicon steel coil 7. The trolley-type annealing furnace includes a furnace car, and the furnace platform 3 of the furnace car is used for placing the grain-oriented silicon steel coil 7.

[0089] As Figures 1 - 2 As shown, the trolley-type annealing furnace of this embodiment includes the protective gas pipeline system for the trolley-type annealing furnace in the above embodiment. The furnace car is located in the furnace cavity 81 of the heating furnace body 8. The structure of the furnace platform 3 of the furnace car includes a bottom frame 32 made of steel structure. A refractory layer 31 is built on the steel frame panel on the upper surface of the bottom frame 32. The exhaust pipe 2 passes through the steel frame panel and is built in the refractory layer 31. It also includes a process detection pipe 4 and a temperature measuring pipe 5, both of which pass through the steel frame panel and are built in the refractory layer 31. A ball valve is equipped at the bottom end of the process detection pipe 4 for connecting a pressure measuring device, and a flange is equipped at the bottom end of the temperature measuring pipe 5 for installing a temperature measuring thermocouple.

[0090] An exhaust gas regulating pipeline unit is arranged in the exhaust pipe group 6. The exhaust path of the waste gas is divided into two paths through the shunt pipe 63 connected to the exhaust pipe 2 in the middle. One path leads to the inside of the furnace cavity 81, and the other path leads to the outside of the furnace cavity 81 through the main discharge pipe 64. During the heating-up and heat-preservation processes of the annealing furnace, the waste gas can be discharged into the furnace cavity 81 to burn the remaining hydrogen, saving fuel. When the annealing furnace is cooling down, the waste gas can be discharged outside the furnace cavity 81, and it will not affect the stability of the atmosphere inside the cover.

[0091] Before the trolley annealing furnace runs, the blind plate on the flange 212 can be removed according to the usage frequency and effect. Then, a compressed air pipeline with a pressure above 0.4 MPa is connected to the port of the flange 212, and compressed air is introduced into the connecting pipe 211 for purging. A large amount of dust particles and scale accumulated on the inner wall of the connecting pipe 211 and at the adapter 213 can be discharged from the waste gas inlet at the upper end of the exhaust pipe 2, achieving the purpose of timely cleaning the pipeline, facilitating the adjustment of the pressure inside the hood, and improving the stability of product quality.

[0092] The above description is an explanation of the present utility model, not a limitation thereof. The scope defined by the present utility model can be seen in the claims. Any form of modification can be made within the protection scope of the present utility model.

Claims

1. A protective gas pipeline system for a trolley-type annealing furnace, characterized in that: It comprises a protective gas pipeline unit, and the protective gas pipeline unit comprises: An exhaust pipe (2), the exhaust pipe (2) being fixedly mounted on the furnace platform (3) of the trolley-type annealing furnace, the air inlet end of the exhaust pipe (2) being located above the furnace platform (3), and the exhaust end of the exhaust pipe (2) being located below the furnace platform (3), An air intake pipe (1), the air intake pipe (1) comprising a straight pipe section (11) and a curved pipe section (12) located below the straight pipe section (11); the exhaust pipe (2) is sleeved outside the straight pipe section (11); the head end of the curved pipe section (12) is connected to the straight pipe section (11); the tail end of the curved pipe section (12) is located outside the exhaust pipe (2) and connected to a process gas delivery pipeline; an inspection pipe (21), the inspection pipe (21) being in communication with the exhaust pipe (2) and being used for removing impurities in the exhaust pipe (2); The protective gas pipeline system further comprises an exhaust pipe (64) and an exhaust gas regulating pipeline unit, wherein the exhaust port of the exhaust pipe (64) is located outside the furnace chamber (81) of the trolley-type annealing furnace. The air inlet end of the exhaust regulating pipeline unit is connected to the exhaust end of the exhaust pipe (2), and the exhaust end of the exhaust regulating pipeline unit is two, which are respectively connected to the exhaust main pipe (64) and the furnace chamber (81).

2. The protective gas pipeline system for a trolley-type annealing furnace according to claim 1, characterized in that: A protective member (22) is installed at the air inlet end of the exhaust pipe (2), and the protective member (22) is used to prevent impurities from entering the exhaust pipe (2).

3. The protective gas pipeline system for a trolley-type annealing furnace according to claim 2, characterized in that: The structure of the protective member (22) is as follows: it comprises a baffle plate (221) of an annular structure, the inner edge of the baffle plate (221) is connected to the outer wall of the straight pipe section (11), the diameter of the outer edge of the baffle plate (221) is adapted to the diameter of the exhaust pipe (2), the outer edge of the baffle plate (221) is connected to the exhaust pipe (2), and a plurality of ventilation holes (222) are provided on the baffle plate (221).

4. The protective gas pipeline system for a trolley-type annealing furnace according to any one of claims 1 to 3, characterized in that: The structure of the inspection pipe (21) comprises a connecting pipe (211), one end of the connecting pipe (211) is connected to the exhaust end of the exhaust pipe (2), and the other end of the connecting pipe (211) is provided with a flange (212), and a blind plate is detachably mounted on the flange (212).

5. The protective gas pipeline system for a trolley-type annealing furnace according to claim 4, characterized in that: The inspection pipe (21) further comprises a transfer pipe (213), wherein the transfer pipe (213) connects the connecting pipe (211) with the exhaust end of the exhaust pipe (2), and at the same time makes the included angle between the axes of the exhaust pipe (2) and the connecting pipe (211) less than 180 degrees.

6. The protective gas pipeline system for a trolley-type annealing furnace according to any one of claims 1 to 3, characterized in that: The exhaust gas regulating pipeline unit comprises a shunt pipe (63), an inner diffusion pipe (62) and an outer diffusion pipe (65); One end of the diverter pipe (63) is in communication with one end of the inner diffusion pipe (62), the other end of the inner diffusion pipe (62) is located in the furnace chamber (81), the other end of the diverter pipe (63) is in communication with one end of the outer diffusion pipe (65), the other end of the outer diffusion pipe (65) is in communication with the main discharge pipe (64), and the middle part of the diverter pipe (63) is in communication with the exhaust pipe (2).

7. The protective gas pipeline system for a trolley-type annealing furnace according to claim 6, characterized in that: The exhaust gas regulating pipeline unit also includes a manifold (61); One end of the converging pipe (61) is in communication with the exhaust pipe (2), and the other end of the converging pipe (61) is in communication with the middle portion of the branching pipe (63).

8. The protective gas pipeline system for a trolley-type annealing furnace according to claim 6, characterized in that: The inner diffusion pipe (62) is provided with an inner diffusion regulating valve (621), and the outer diffusion pipe (65) is provided with an outer diffusion regulating valve (651).

9. The protective gas pipeline system for a trolley-type annealing furnace according to claim 1, characterized in that: The number of the protective gas pipeline units and the exhaust gas regulating pipeline units are both multiple groups and correspond one to one, and multiple sets of protective gas pipeline units and exhaust gas regulating pipeline units are distributed in arrays on the furnace platform (3).

10. A trolley type annealing furnace, characterized in that: It comprises a protective gas pipeline system for a trolley-type annealing furnace as described in any one of claims 1 to 9, wherein the trolley-type annealing furnace is used for heat treatment of oriented silicon steel coils (7), and the trolley-type annealing furnace comprises a furnace car, and the furnace table (3) of the furnace car is used to place the oriented silicon steel coils (7).

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