A method and equipment for heating steel billets in a multi-flow combined roller hearth furnace

Abstract

This invention discloses a method for heating steel billets in a multi-flow combined roller hearth furnace. Steel billets are supplied sequentially or simultaneously to multiple independent and movable roller hearth furnaces via one or more charging roller conveyors. The billets are heated in one or more furnaces by oscillating back and forth or in a relay heating manner. The charging roller conveyors may also be discharge roller conveyors. The equipment consists of multiple independent and movable or rotatable roller hearth furnaces. These furnaces move horizontally, vertically, or rotate to align with the charging roller conveyors, loading steel billets one by one. After simultaneous or sequential heating, the furnaces move or rotate to align with the discharge roller conveyors, allowing the heated billets to exit one by one. This method enables the selection and sequencing of heating times for each billet, adapting to the different heating requirements of each billet. Combined with the oscillating heating within the furnace, it effectively saves energy and possesses strong practicality and wide applicability.

Description

Technical Field

[0001] This invention relates to a method for heating steel billets, specifically to a method and equipment for heating steel billets in a multi-flow combined roller hearth furnace, belonging to the field of metallurgy. Background Technology

[0002] In the steel and non-ferrous metallurgical industries, the billet heating process uses a single furnace. The billets are ordered and enter the furnace one by one. Multiple billets are heated in the furnace at the same time, and then ordered and leave the furnace one by one.

[0003] Traditional billet heating processes have the following drawbacks: 1. The order in which billets enter and leave the heating furnace cannot be adjusted, and the heating time for each billet is the same, making it impossible to dynamically adjust the heating time for different billets; 2. The temperature control of all billets in a single furnace is simultaneous, and individual adjustment for each billet is not possible; 3. Only one billet can enter or leave at a time, making the scheduling of material entry and exit inflexible; 4. Because all billets are heated simultaneously in the same furnace, the number of billets to be heated cannot be flexibly selected, and the opening and closing of the heating furnace is not flexible enough. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a method and equipment for heating steel billets in a multi-flow combined roller hearth furnace.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for heating steel billets in a multi-flow combined roller hearth furnace involves supplying steel billets sequentially or simultaneously to multiple independent and movable roller hearth furnaces via one or more charging roller conveyors. The steel billets are heated in one or more roller hearth furnaces by oscillating back and forth or by relay heating.

[0007] The loading roller conveyor may be the discharge roller conveyor.

[0008] The aforementioned methods of moving the roller hearth furnace include: planar translation, planar rotation, suspended rotation, lifting and lateral movement.

[0009] The above-mentioned multiple roller hearth furnaces can be arranged in the following ways: horizontal grouping, horizontal multi-group rowing, vertical multi-group columning, and vertical suspended rotating type.

[0010] Each roller hearth furnace can hold one or more steel billets.

[0011] The feed inlet and discharge outlet of the aforementioned roller hearth furnace are located at either end of the roller hearth furnace or at the same end.

[0012] The loading roller conveyor is connected to the inlet, and the discharge roller conveyor is connected to the outlet.

[0013] Furthermore, the aforementioned loading roller conveyor and discharging roller conveyor may or may not be collinear.

[0014] The equipment applicable to the above-mentioned method of heating steel billets in a multi-flow combined roller hearth furnace includes a charging roller conveyor, a discharging roller conveyor, and several roller hearth furnaces;

[0015] The aforementioned roller hearth furnaces are respectively connected to the charging roller conveyor and the discharging roller conveyor via mobile equipment in the horizontal or vertical direction. The charging roller conveyor supplies steel billets to the roller hearth furnaces, and the discharging roller conveyor outputs steel billets.

[0016] Furthermore, the aforementioned loading roller conveyor may be a discharge roller conveyor.

[0017] Furthermore, the aforementioned discharge roller conveyor can be one or more, and the multiple discharge rollers may be on the same straight line or not collinear.

[0018] Furthermore, the aforementioned mobile device includes a horizontal slide rail, a flat turntable, a vertical hanging rail, and a vertically rotating chain.

[0019] The advantages of this invention are:

[0020] This invention discloses a method and apparatus for heating steel billets in a multi-flow combined roller hearth furnace. By utilizing multiple independent, movable, or rotatable roller hearth furnaces, the steel billets are uniformly heated within each furnace through the back-and-forth oscillation of the furnace rollers. Through the operation of each roller hearth furnace, the steel billets can be selectively loaded into the furnace for individual heating, or combined in a relay heating manner, and then selectively removed from the furnace, achieving flexible and dynamic heating of the steel billets. It can also independently heat steel billets at different temperatures for different durations, and can simultaneously heat multiple billets entering or exiting the furnace, enabling rapid opening and closing of any one roller hearth furnace.

[0021] The method and equipment for heating steel billets in a multi-flow combined roller hearth furnace of the present invention realizes the selection and sequencing of heating time for a single steel billet, adapts to the different heating requirements of each steel billet, and effectively saves energy by combining the swing heating in the furnace. It has strong practicality and wide applicability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a sliding rail type multi-flow combined roller hearth furnace.

[0023] Figure 2 for Figure 1 A cross-sectional view of the structural schematic diagram.

[0024] Figure 3 This is a schematic diagram of a multi-flow combined roller hearth furnace with multiple loading roller tracks and sliding rails.

[0025] Figure 4 This is a schematic diagram of a rotary multi-flow combined roller hearth furnace.

[0026] Figure 5 This is a schematic diagram of a multi-flow combined roller hearth furnace with a suspended rail (Figure a shows multiple columns, Figure b shows a single column).

[0027] Figure 6 This is a schematic diagram of a chain-belt type multi-flow combined roller hearth furnace.

[0028] The meanings of the markings in the attached diagram are as follows: 1. Roller hearth furnace, 2. Steel billet, 3. Charging roller conveyor, 4. Inner furnace roller, 5. Discharge roller conveyor, 6. Beam seat, 7. Chain belt, 8. Turntable. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0030] The roller hearth furnace has a long, tunnel-like furnace chamber with the feed inlet and discharge outlet located at the ends. A heating device is installed inside the furnace chamber, which can be heated by fuel or electricity. The inner walls of the furnace chamber, including the inner side, top, and bottom surfaces, are all made of refractory insulation material. Several internal rollers are arranged along the length of the furnace chamber to form an internal roller group, with at least one roller being the driving roller and the others being driven rollers. The steel billet is uniformly heated inside the roller hearth furnace by the back-and-forth oscillation of the internal rollers. Depending on the application requirements, at least one or more internal roller groups can be installed inside the furnace chamber, meaning each roller hearth furnace can accommodate one or more steel billets. The heating device within each roller hearth furnace is controlled separately by a control unit.

[0031] Example 1

[0032] like Figure 1 and Figure 2 As shown, preferably, four roller hearth furnaces are arranged as a group and fixed horizontally on a beam support. The bottom of the beam support is equipped with a horizontal slide rail. The horizontal slide rail can be composed of several pulleys located at the bottom of the beam support and a slide rail perpendicular to the length of the roller hearth furnace. The control device drives the pulleys to roll along the slide rail via a motor.

[0033] Along the length of the roller hearth furnace, one end of the roller hearth furnace is the feed inlet and the other end is the discharge outlet; on both sides of the slide, there are symmetrical loading roller tracks and discharge roller tracks that are connected to the feed inlet and discharge outlet respectively.

[0034] In use, the control device drives the pulley to roll along the slide, so that the feed port of one of the roller hearth furnaces is connected to the loading roller track.

[0035] The charging roller conveyor feeds the steel billet into the roller hearth furnace. The control device drives the pulley to roll along the slide. After leaving the charging roller conveyor position, the heating device is driven to heat the billet. When the heating reaches the required level, the control device drives the pulley to roll along the slide, so that the discharge port and the discharge roller conveyor are connected. The billet is then transferred out by the furnace roller and enters the discharge roller conveyor.

[0036] When the steel billet is heated in the roller hearth furnace, the control device can drive the pulley to roll along the slide, so that the feed port of another roller hearth furnace is connected to the charging roller conveyor, and the charging roller conveyor then sends another steel billet into the roller hearth furnace for heating.

[0037] The billet can be a square or rectangular billet made of carbon steel with a cross section thickness of 150-200mm, each 12m long. The temperature of the billet can be room temperature to 900℃. After being heated to 1050℃ in a roller hearth furnace, it is sent out for rolling. The heating time in the roller hearth furnace varies depending on the temperature of the incoming material. Steel is tapped after the temperature meets the requirements.

[0038] Correspondingly, the roller hearth furnace is equipped with a billet temperature detection device. The control device drives the rolling of the pulley and the movement mode of the inner rollers according to the feedback of the temperature detection device: that is, when the billet temperature is less than 1050℃, the inner rollers rotate reciprocally, so that the billet swings back and forth in the roller hearth furnace for heating; when the billet temperature is greater than or equal to 1050℃, the inner rollers rotate unidirectionally to send the billet out of the roller hearth furnace.

[0039] Example 2

[0040] like Figure 3 As shown, based on the structure of Example 1, three roller hearth furnaces are used as a group.

[0041] The loading roller conveyor has three flow channels, and the discharge roller conveyor has a single flow channel. The discharge roller conveyor is on the same straight line as one of the loading roller conveyors.

[0042] In use, the three-channel charging roller conveyor improves the efficiency of billet feeding, allowing for sequential or simultaneous feeding of three roller hearth furnaces. The control device, based on the billet temperature, sequentially connects the three roller hearth furnaces to the discharge roller conveyor, and then connects the empty roller hearth furnace to the charging roller conveyor with the prepared billets. After feeding, the billets are heated, and this process is repeated.

[0043] For example Figure 3 Taking the structure shown as an example, different roller hearth furnaces can be set with different heating temperatures. For example, the first roller hearth furnace can be heated to 500°C, the second roller hearth furnace to 900°C, and the third roller hearth furnace to 1050°C. The corresponding billet temperature supplied by the first charging roller conveyor is room temperature to 500°C, the billet temperature supplied by the second charging roller conveyor is room temperature to 500-900°C, and the billet temperature supplied by the third charging roller conveyor is 900-1050°C.

[0044] When the billet temperature is heated to 500°C in the first roller hearth furnace, the control device drives the first roller hearth furnace to connect with the second charging roller conveyor. The second charging roller conveyor receives the billet sent from the first roller hearth furnace and then sends the billet into the second roller hearth furnace. When the billet is heated to 900°C in the second roller hearth furnace, the third charging roller conveyor receives the billet sent from the second roller hearth furnace and then sends the billet into the third roller hearth furnace. When the billet is heated to 1050°C in the third roller hearth furnace, the third roller hearth furnace sends the billet into the discharge roller conveyor.

[0045] In this structure, the first and second roller hearth furnaces are preheating furnaces. By setting different furnace temperatures and heating temperatures, heat can be saved and heating efficiency improved. At the same time, when the supplied steel billets are at different temperatures, they can be selectively fed directly into the first, second, and third charging roller conveyors.

[0046] Example 3

[0047] like Figure 4 As shown, the mobile device is a flat turntable.

[0048] The roller hearth furnace is set along the radius of the turntable. Along the circumference, there are several roller hearth furnaces, each driven by a control device. The feed inlet and discharge outlet of the roller hearth furnace are both on the outer side, and the inner side of the roller hearth furnace near the center of the turntable is the closed end.

[0049] Along the extension of the diameter of the turntable, a loading roller track and a discharging roller track are respectively set on both sides of the turntable.

[0050] In operation, the charging roller conveyor sequentially supplies steel billets to each roller hearth furnace. Once the steel billet in one of the roller hearth furnaces has been heated to the required temperature, the control device drives the turntable to rotate, aligning the roller hearth furnace with the discharge roller conveyor. The furnace rollers then feed the steel billet back into the discharge roller conveyor. The control device then rotates the turntable to align an empty roller hearth furnace with the charging roller conveyor; this process is repeated.

[0051] Example 4

[0052] like Figure 5 As shown, the mobile equipment is a longitudinal hanging rail. The arrangement of the roller hearth furnace can be as shown in Figure a, with two roller hearth furnaces arranged in a transverse direction as a group, and then the two groups arranged in a longitudinal direction as two columns; or as shown in Figure b, with four roller hearth furnaces arranged in a single column along the longitudinal direction.

[0053] Depending on the usage requirements, the feed inlet and discharge outlet can be located at both ends of the roller hearth furnace or at the same end.

[0054] In use, the control device drives the longitudinal and lateral movement of the lifting rails, so that each roller hearth furnace connects with the charging roller conveyor and the discharging roller conveyor in sequence.

[0055] Example 5

[0056] like Figure 6 As shown, the mobile device is a vertically rotating chain.

[0057] The top of the chain can be controlled by a control device via a toothed disc.

[0058] Several roller hearth furnaces are suspended at intervals on the outer side of the chain belt, with charging rollers and discharging rollers set at any height.

[0059] Depending on the usage requirements, the feed inlet and discharge outlet can be located at both ends of the roller hearth furnace or at the same end.

[0060] In use, the control device drives the chain belt to rotate, so that each roller hearth furnace connects to the charging roller conveyor and the discharging roller conveyor in sequence.

[0061] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A method for heating steel billets in a multi-flow combined roller hearth furnace, characterized in that, Steel billets are supplied sequentially to multiple independent and moving roller hearth furnaces via multiple charging roller conveyors. The steel billets are then heated in a relay manner by oscillating back and forth within the multiple roller hearth furnaces. Different roller hearth furnaces are set to different heating temperatures. After the steel billet is heated in the first roller hearth furnace, the control device drives the first roller hearth furnace to connect with the second charging roller conveyor. The second charging roller conveyor receives the steel billet sent out by the first roller hearth furnace and then sends the steel billet into the second roller hearth furnace. After the steel billet is heated in the second roller hearth furnace, the third charging roller conveyor receives the steel billet sent out by the second roller hearth furnace and then sends the steel billet into the third roller hearth furnace. After the steel billet is heated in the third roller hearth furnace, the third roller hearth furnace sends the steel billet into the discharge roller conveyor. The charging roller conveyor is connected to the feed inlet, and the discharging roller conveyor is connected to the discharge outlet. The feed inlet and the discharge outlet are located at both ends or at the same end of the roller hearth furnace. The movement methods of the roller hearth furnace include: planar translation, planar rotation, suspended rotation, lifting and lateral movement; The arrangement of the multiple roller hearth furnaces includes: transverse grouping, transverse multi-group rowing, longitudinal multi-group columning, and longitudinal suspended rotating type.

2. The method according to claim 1, characterized in that, Each roller hearth furnace can hold one or more steel billets.

3. The method according to claim 1, characterized in that, The loading roller conveyor and the discharging roller conveyor are either on the same straight line or not collinear.

4. An apparatus suitable for heating steel billets in a multi-flow combined roller hearth furnace according to any one of claims 1-3, characterized in that, Includes discharge roller conveyor, multiple charging roller conveyor, and multiple roller hearth furnaces; The multiple roller hearth furnaces are connected to the charging roller conveyor and the discharging roller conveyor via mobile equipment in the horizontal or vertical direction. The charging roller conveyor supplies steel billets to the roller hearth furnace, and the discharging roller conveyor outputs the steel billets.

5. The device according to claim 4, characterized in that, The mobile device includes a horizontal slide rail, a flat turntable, a longitudinal hanging rail, and a longitudinally rotating chain.

Images