CN108405618A - A kind of long material endless rolling connection method and its rolling line - Google Patents

Abstract

The invention discloses a kind of long material endless rolling connection method and its rolling lines, belong to long product rolling field, the endless rolling connection method is that will be welded to connect by friction welding (FW) head and the tail continuously across base among base among the preceding block of crop flying shear after roughing mills and rear block, and implement edge burr removal processing in the welding position of the two.The present invention carries out intermediate base connection after roughing mills and realizes long material endless rolling, effectively reduce the failure rate during excellent steel wire bar production, improve lumber recovery, reduce energy consumption, improve income, and specification rolling is become by the whole realization of roll gap on-line fine, and reduce wedge-shaped segment length when becoming specification, improve lumber recovery.

Description

A long material endless rolling connection method and rolling production line thereof

technical field

The invention belongs to the technical field of endless rolling of long products in the iron and steel metallurgical industry, and in particular relates to a connection method for endless rolling of long products and a rolling production line thereof.

Background technique

As one of the important products in the steel industry, wire rods are widely used in construction, machinery and metal products industries. In addition, excellent special steel bar products are also widely used in metallurgy, machinery, automobiles, mines, bridges and railway construction and other industrial fields.

At present, the conventional production method of wire and rod is to use multi-strand continuous casting machine to produce billet or round billet, cut the cast billet and send it to the heating furnace through the hot delivery roller table, and the heating furnace will heat the cast billet and send it to the rolling mill Rolling is performed. The specific process flow is as follows: continuous casting machine→drawing and leveling machine→cutting machine→conveyor roller table→steel shifting machine→steel separator→hot feeding roller table→heating furnace bench→heating furnace→rough rolling unit→intermediate rolling unit→finishing Rolling unit → collection device. Among them, the multi-strand slabs need to be transferred to the rack of the steel splitter in batches by the steel transfer machine, and then placed one by one on the hot-sending roller table by the steel-splitting machine, and transported to the heating furnace by the hot-sent roller table for heating. Then sent to the rolling mill for rolling. There are many problems and deficiencies in this production method: 1) The production process is long and the temperature loss is high. If it is directly hot-sent, the temperature will be too low when it reaches the entrance of the rolling mill, resulting in a substantial increase in the power of the rolling mill. 2) In the production process, each rolling unit needs to cut the head, and the tail of the billet needs to be cut, which reduces the yield; 4) The single rolling time is short, and there are frequent steel biting and steel throwing processes, which cannot achieve stability online roll gap adjustment.

In order to solve the above problems, many experts and scholars have proposed a variety of methods. The invention patent "Continuous Casting-Direct Rolling Device and Method for Producing Rods, Wires and Profiles" (CN104550237A) proposes a continuous casting and rolling method for profiled rods and wires. The heat preservation cover is used for heat preservation, and the surface temperature of the casting slab in the roughing mill will drop to about 900°C, and the core temperature will only be 950°C, which cannot meet the rolling requirements of high-quality special steel. The invention patent "Continuous Casting and Rolling Method for Producing Profile Bars and Wires Using Waste Heat of Molten Steel" (CN102310078A) proposes a continuous casting and rolling method for profile bars and wires. Low, the shortcomings of too many rolling mills and too much investment when using multi-stream production. Invention patent "A device for producing steel bars by rolling billets without heating at low temperature and its production method" (CN103480647A) Although the heating furnace is canceled, the device uses multiple rows of continuous casting slabs in parallel, and then divides the steel by a horizontal allocation device The method of single feeding into the hot-feeding roller table will cause the continuous casting slab to enter the hot-feeding roller table for a long time and the temperature drop will be too large, and the cooling time of the continuous casting slab will be increased due to the need to move the steel horizontally , it can be seen that there is no essential difference between this device and the current commonly used hot feeding and hot charging technology. The temperature drop of the continuous casting slab is too large to meet the rolling requirements of the rolling mill, so it is not feasible. The invention patent "Continuous casting and rolling device for producing long products" (CN202667242U) uses a roller hearth heating furnace to heat the continuous casting slab. Although the traditional heating furnace is cancelled, there are still high investment in equipment, and the production still consumes a lot of electric energy or fuel. The problem of large oxidation burning loss.

Contents of the invention

The technical problem to be solved by the present invention is to provide a long material endless rolling connection method and its rolling production line in view of the above-mentioned deficiencies in the prior art, which have the advantages of simple process layout, relatively simple connection method, low cost, and easy industrial production , has obvious economic benefits.

The present invention is achieved through the following technical solutions:

The invention provides a long product endless rolling connection method, which connects the front middle billet rolled piece and the rear middle middle billet rolled piece through friction welding head to tail after passing through the rough rolling unit continuously, and at the welding position of the two Implement edge deburring.

Preferably, before the friction welding welding, the front block middle billet is cut head and tail and the back block middle billet is cut by the rear head cutting flying shear of the roughing rolling mill, and the back block middle billet is rolled The piece catches up with the front piece, the middle billet rolled piece, until the two are synchronized.

Preferably, the total time is less than 20s from the start of catching up with the rear middle billet to the end of burr removal.

Preferably, during friction welding, when the temperature of the welding surface of the rear block middle billet and the front middle billet reaches 950°C to 1050°C, an upsetting pressure is applied to complete the welding; the friction welding method is linear friction or rotation Friction, upsetting pressure is 30MPa ~ 100MPa.

The present invention also provides an endless rolling production line for long products, which includes a continuous casting machine, a heating furnace, a rough rolling unit, a cutting flying shear, an intermediate rolling unit, a finishing rolling unit and a collecting unit arranged in sequence, and the collecting unit is Any one of the cooling bed, coil collection system or wire rod collection system, also includes an intermediate billet connection device, which is arranged after the head cutting flying shear and before the intermediate rolling unit to realize the above-mentioned endless rolling connection method, including clamping clamping mechanism, friction mechanism, burr removal mechanism, transmission mechanism and upsetting mechanism, the clamping mechanism includes a rear clamping piece for clamping the middle billet of the rear block and a front clamping piece for clamping the middle billet of the front block A clip, the friction mechanism includes a supporting part, a moving part and a friction head, the supporting part is arranged on the moving part, the friction head is arranged on the supporting part, the transmission mechanism acts on the friction head, and the upsetting mechanism acts on the rear clip ; The friction head is a friction knife or a friction disc.

Further, the endless rolling production line also includes setting a reducing and sizing unit behind the finishing rolling unit; wire mill unit; or the endless rolling production line also includes setting a pre-finishing unit before the finishing unit, and setting a reducing and sizing unit and a laying unit in sequence after the finishing unit.

Further, the rough rolling group adopts non-slot rolling, and the rough rolling group and the intermediate rolling group adopt head-off rolling.

Further, the finishing rolling unit or the reducing and sizing unit is equipped with an online roll gap adjustment device.

The present invention is specifically implemented as follows:

(1) The connecting device of the intermediate billet is located behind the rough rolling unit and in front of the intermediate rolling unit. Since the rough rolling unit and the intermediate rolling unit do not adopt continuous rolling, it can effectively increase the biting speed of the rough rolling unit and reduce the The hot roll phenomenon caused by it, and improve the production capacity of the production line;

(2) The continuous casting in front of the rough rolling unit adopts multi-strand continuous casting to provide billets to ensure the inlet flow and thus the production line output;

(3) Through endless rolling, it can be cut according to the actual demand. For the bar production line, it can be cut according to the fixed length. For the wire production line, it can be cut according to the production capacity of the collection device such as the core frame. ;

(4) For endless rolling, only rough rolling, intermediate rolling, finishing rolling, etc. are cut at the head of the billet, and then only need to be cut according to the demand, which greatly reduces the cutting loss of the head and tail, without replacing the rolls Continuous production can be carried out for 5-6 hours under certain conditions. The production time depends on the wear of the roll, especially the wear of the roll ring of the finishing unit or the reducing and sizing unit that requires high precision control, so as to improve labor productivity;

(5) When the intermediate billet is connected, the welding machine and the intermediate billet run synchronously. After the front intermediate billet passes through the rough rolling unit, the head and tail are cut first, and the rear intermediate billet is cut. , carry out the catch-up process, and after being synchronized with the rolling piece of the front middle billet, use friction welding to perform linear friction or rotational friction on the connecting surface, and perform upsetting welding when the temperature of the welding surface reaches 950°C-1050°C, and the unit is upsetting The pressure is 30MPa～100MPa. After the connection is completed, the edge burrs are removed. The total time is less than 20s from the beginning of catching up with the middle billet of the rear block to the end of burr removal. Head rolling, which can guarantee the connection rhythm matching;

(6) The rough rolling unit adopts no-hole rolling to improve productivity and reduce roll wear;

(7) The upstream adopts two-strand or three-strand continuous casting slabs, which is mainly limited by the current continuous casting speed, and there is a big bottleneck for high-quality steel varieties in order to ensure the post-rolling performance by adopting the non-heating rolling production method. Steel production efficiency and yield, and for production lines mainly made of threaded steel and ordinary steel, with the increase of continuous casting speed, the production method of heating-free rolling or continuous casting and rolling can be adopted;

(8) In order to ensure the dimensional accuracy of bar or wire products, the last few stands of the endless rolling production line are equipped with online roll gap adjustment devices. For bar production lines, it is generally a finishing rolling unit or bar reducing and sizing unit. Generally, it is a finishing mill or a wire rod reducing and sizing unit. During production, the influence of roll wear on product size accuracy is controlled by means of online roll gap adjustment, and the caliper after the finishing mill or reducing and sizing unit feeds back the rolled piece in real time. Size, and real-time control of the roll gap;

(9) When adjusting the online roll gap, in order to reduce the length of the transition zone, it is necessary to carry out fine adjustments online. Before and after the specification of the rolled piece is changed, the dimensional tolerance can be guaranteed to meet the requirements of the product user. This adjustment method can reduce the scrap rate; for example, the front block The specification of the intermediate billet is Φ20mm bar, and the specification can be changed to 20.5mm under the condition of meeting the accuracy of GB-T702-2008 Group 1.

The advantages of the present invention are:

1) The intermediate billet connection device is located behind the roughing unit and in front of the intermediate rolling unit. Since the roughing unit and the intermediate rolling unit do not adopt continuous rolling, the biting speed of the roughing unit can be increased, and the production capacity of the production line can be increased;

2) Through endless rolling, it can be cut according to actual needs, and the production flexibility is high. For the bar production line, it can be cut according to the fixed length. For the wire production line, it can be produced according to the collection device such as the core frame ability to cut

3) Adopting this endless rolling production process can greatly reduce the cutting loss of the head and tail in the production process, and the yield rate of the finished product is increased by 0.5-1.5% compared with the ordinary production line. It can be continuously produced for 5-6 hours without changing the rolls, which improves labor efficiency. productivity;

4) The rough rolling unit adopts no-hole rolling to reduce roll wear;

5) When the intermediate blank is connected, the welding machine and the rolled piece run synchronously, and the entire connection process takes less than 20s, which can ensure the matching of the connection rhythm and improve productivity;

6) It can greatly improve the production efficiency and yield of high-quality steel;

7) On-line micro-adjustment of the roll gap reduces the length of the wedge section when the specification of the rolled piece is changed, and improves the yield.

Other advantages, objects and features of the present invention will be set forth in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the investigation and research below, or can be obtained from Taught in the practice of the present invention. The objects and other advantages of the invention may be realized and attained by the following specification.

Description of drawings

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with the accompanying drawings, wherein:

Fig. 1 is a schematic diagram of the layout of Embodiment 1 of the bar endless rolling production line of the present invention;

Fig. 2 is a schematic layout diagram of embodiment 2 of the bar endless rolling production line of the present invention;

Fig. 3 is a schematic layout diagram of Embodiment 1 of the high-speed wire rod endless rolling production line of the present invention;

Fig. 4 is a schematic layout diagram of Embodiment 2 of the high-speed wire rod endless rolling production line of the present invention;

Fig. 5 is a schematic diagram of the endless rolling connection device of the present invention;

Reference signs in the figure: continuous casting machine 1, heating furnace 2, rough rolling unit 3, cutting head flying shear 4, intermediate rolling unit 5, pre-finishing rolling unit 6, finishing rolling unit 7, reducing and sizing unit 8, spinning Machine unit 9, collection unit 10, intermediate billet connection device 11; rear clamping member 111, front clamping member 112, support member 113, moving member 114, friction head 115, burr removal mechanism 116, transmission mechanism 117, upsetting mechanism 118; The rolling piece of the middle billet of the rear block, the rolled piece of the middle billet of the front block of A; the front block represents the direction of rolling production.

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments are only schematically illustrating the basic concept of the present invention, and the following embodiments and the features in the embodiments can be combined with each other in the case of no conflict.

Example 1

Referring to Fig. 1 and Fig. 5, according to the present invention, the production process sequence includes: continuous casting machine 1 continuous casting, heating furnace 2 heating, rough rolling unit 3 rolling, cropping flying shear 4 shearing, intermediate billet connecting device 11 welding, 5 rolling in the middle rolling group, 7 rolling in the finishing rolling group, 8 rolling in the reducing and sizing group, and cooling in the collecting unit 10 (cooling bed). The process is as follows:

(1) Continuous casting: Multi-machine multi-strand or single-click multi-strand continuous casting machines are used to produce billets or rectangular billets, and the cross-section of continuous casting billets is 150mm×150mm～180mm×180mm or equal-area rectangular billets;

(2) The continuous casting slab in step (1) is heated and kept in a walking beam heating furnace, and the heating temperature is 950°C to 1300°C;

(3) Rough rolling unit rolling: the square billet heated in step (2) is rolled by the rough rolling unit for 6 passes without grooves, and for the rectangular billet, it is rolled for 5 passes. Pass or 7-pass rough rolling unit rolling without holes. During rolling, there are guides at the front and back of each rolling mill, and flying shears are installed behind the rough rolling unit. During the rolling process, the deformation temperature of each pass is controlled at 900 ℃～1100℃, the running speed of the billet during the rolling process of the rough rolling unit is 0.15m/s～2.00m/s;

(4) Welding of the intermediate blank device: the intermediate blank connecting device 11 is arranged after the cutting head flying shear 4 and before the intermediate rolling unit 5, and is used to realize the endless rolling connection method, including a clamping mechanism, a friction mechanism, and a burr removal mechanism 116. Transmission mechanism 117 and upsetting mechanism 118. The clamping mechanism includes a rear clamping member 111 for clamping the middle billet A of the rear block and a front clamping member 112 for clamping the middle billet B of the front block , the friction mechanism includes a supporting part 113, a moving part 114 and a friction head 115, the supporting part is arranged on the moving part, the friction head is arranged on the supporting part, the transmission mechanism acts on the friction head, and the upset mechanism acts on the rear clamp superior. Concretely, after the front block middle billet rolling piece B is cut head and tail by the rough rolling mill, the middle billet connection device 11 and its tail are synchronously operated, and after the rear block middle billet A cuts the head, it accelerates to catch up with the front After the interval between the rolling pieces B of the middle block is 20-100mm, the rotating friction welding piece or the linear friction welding piece performs fast linear or rotating friction on the tail of the front middle rolling piece B and the head of the rear middle rolling piece A synchronously, When the temperature of the welding surface reaches 950 ℃ ~ 1050 ℃, carry out upsetting welding. The unit upsetting force is 30MPa ~ 100MPa. After the connection is completed, remove the edge burrs. The calculation starts from the catch-up of the next rolled piece until the end of burr removal. , the total time is less than 20s; then the rear intermediate blank connecting device 11 is moved to the initial position, and the subsequent connecting process of the rear intermediate blank rolled piece is carried out.

(5) Rolling in the middle rolling group: the billet connected in step (4) is rolled in the middle rolling group, the bite temperature of the middle rolling group is 850°C to 1000°C, and the rolling speed during the rolling process is 0.2m/ s～6.0m/s;

(6) Finish rolling and reducing and sizing unit rolling: the rolled piece after the rolling unit rolling in the step (5) is carried out successively to finish rolling unit, reducing and sizing unit rolling, in order to guarantee product quality in finishing rolling unit and reducing sizing unit rolling Water-cooled controlled cooling before and after the sizing unit and rolling at low temperature and high pressure in the reducing and sizing unit. The rolling temperature is 700℃～950℃, and the running speed of the rolled piece is 5m/s～25.0m/s during the rolling process; in addition, the online roll gap adjustment is configured in the reducing and sizing unit, and the production is controlled by the online roll gap adjustment method The impact of roll wear on product size accuracy, and the caliper at the end of the stand gives real-time feedback on the size of the rolled piece, and realizes real-time fine-tuning of the roll gap; the single adjustment amount of the online roll gap adjustment is less than the size tolerance range before and after the specification change or the user's size Tolerance requirements.

(7) Cooling bed cooling: the rolled piece rolled by the step (6) reducing and sizing unit is first controlled and cooled to obtain the ideal microstructure and better mechanical properties of the product, and the rolled piece is sheared by double-scale flying shear 1. After the cooling bed is cooled, it is collected.

Example 2

Referring to Fig. 2 and Fig. 5, according to the present invention, the production process sequence includes: continuous casting by continuous casting machine, heating by heating furnace, rolling by rough rolling unit, cutting head and flying shear, welding of intermediate billet connecting device, rolling by intermediate rolling unit , The process of rolling in the finishing rolling mill and cooling in the cooling bed is as follows:

(1) Continuous casting: Multi-machine multi-strand or single-click multi-strand continuous casting machines are used to produce billets or rectangular billets, and the cross-section of continuous casting billets is 150mm×150mm～180mm×180mm or equal-area rectangular billets;

(2) The continuous casting slab in step (1) is heated and kept in a walking beam heating furnace, and the heating temperature is 950°C to 1300°C;

(3) Rough rolling unit rolling: the square billet heated in step (2) is rolled by the rough rolling unit for 6 passes without grooves, and for the rectangular billet, it is rolled for 5 passes. Pass or 7-pass rough rolling unit rolling without holes. During rolling, there are guides at the front and back of each rolling mill, and flying shears are installed behind the rough rolling unit. During the rolling process, the deformation temperature of each pass is controlled at 900 ℃～1100℃, the running speed of the billet during the rolling process of the rough rolling unit is 0.15m/s～2.00m/s;

(4) Welding of the intermediate billet device: After the front block of the intermediate billet is cut head and tail by the rough rolling mill, the intermediate billet connecting device and its tail will run synchronously, and after the rear block of the intermediate billet is cut, it will be accelerated to catch up. After the distance between the rolled piece and the middle billet of the front block is 20-100mm, the rotating friction welding piece or the linear friction welding piece is used to perform fast linear or rotating friction on the tail of the rolled piece of the front middle billet and the head of the rolled piece of the rear middle billet synchronously. The temperature of the welding surface reaches 950℃～1050℃, and the upsetting welding is carried out. The unit upsetting force is 30MPa～100MPa. After the connection is completed, the edge burrs are removed, and the calculation starts from the catch-up of the rolled piece in the middle of the rear block, and the deburring ends. , the total time is less than 20s; then the rear intermediate billet connecting device moves to the initial position, and the subsequent connecting process of the rear intermediate billet rolled piece is carried out.

(5) Rolling in the middle rolling group: the billet connected in step (4) is rolled in the middle rolling group, the bite temperature of the middle rolling group is 850°C to 1000°C, and the rolling speed during the rolling process is 0.2m/ s～6.0m/s;

(6) Rolling by the finishing mill: carry out rolling by the milling mill to the rolled piece after rolling by the milling mill in step (5), in order to ensure the quality of the product, carry out water-cooling control cooling before and after the milling mill and low temperature and high pressure of the milling mill Rolled down. The rolling temperature is 700℃～950℃, and the running speed of the rolled piece is 5m/s～25.0m/s during the rolling process; in addition, the online roll gap adjustment is configured in the finishing rolling unit, and the rolls are controlled by the online roll gap adjustment method during production. The impact of wear on the dimensional accuracy of the product, and the caliper at the end of the stand will feed back the size of the rolled piece in real time, and realize the real-time micro-adjustment of the roll gap; the single adjustment amount of the online roll gap adjustment is less than the size tolerance range before and after the specification change or the user's size tolerance Require.

(7) Cooling bed cooling: the rolled piece after the step (6) finishing rolling mill rolling is first carried out controlled cooling, in order to obtain ideal microstructure and better mechanical properties of the product, the rolled piece is sheared by double ruler flying shear, After the cooling bed is cooled, it is collected.

Example 3

Referring to Fig. 3 and Fig. 5, according to the present invention, the production process sequence includes: continuous casting by continuous casting machine, heating by heating furnace, rolling by rough rolling unit, cutting head and flying shear, welding of intermediate billet connecting device, rolling by intermediate rolling unit , Pre-finishing mill rolling, finishing mill rolling, reducing and sizing mill rolling, silk laying machine spinning, air-cooling line cooling, core stand coiling, PF line cooling. The process is as follows:

(1) Continuous casting: Multi-machine multi-strand or single-click multi-strand continuous casting machines are used to produce billets or rectangular billets, and the cross-section of continuous casting billets is 150mm×150mm～180mm×180mm or equal-area rectangular billets;

(2) The continuous casting slab in step (1) is heated and kept in a walking beam heating furnace, and the heating temperature is 950°C to 1300°C;

(3) Rough rolling unit rolling: the square billet heated in step (2) is rolled by the rough rolling unit for 6 passes without grooves, and for the rectangular billet, it is rolled for 5 passes. Pass or 7-pass rough rolling unit rolling without holes, and flying shears are installed behind the rough rolling unit. The speed is 0.15m/s～2.00m/s;

(4) Welding of the intermediate billet connecting device: After the front block of the intermediate billet is cut head and tail by the rough rolling mill, the intermediate billet connecting device and its tail run synchronously. After the distance between the rolled piece and the middle billet of the front block is 20-100mm, the rotating friction welding piece or the linear friction welding piece is used to perform rapid linear or rotational friction on the tail of the rolled piece of the front middle billet and the head of the rolled piece of the rear middle billet synchronously, When the temperature of the welding surface reaches 950 ℃ ~ 1050 ℃, carry out upsetting welding. The unit upsetting force is 30MPa ~ 100MPa. After the connection is completed, remove the edge burrs, starting from the catch-up of the rolled piece in the middle of the rear block, until the burrs are removed Finished, the total time is less than 20s; then the rear intermediate billet connecting device moves to the initial position, and the subsequent connecting process of the rear intermediate billet rolled piece is carried out.

(5) Rolling in the middle rolling group: the billet connected in step (4) is rolled in the middle rolling group, the bite temperature of the middle rolling group is 850°C to 1000°C, and the rolling speed during the rolling process is 0.2m/ s～6.0m/s;

(6) Pre-finishing rolling mill, finishing rolling mill and reducing and sizing mill rolling: carry out pre-finishing rolling mill rolling, finishing mill mill rolling and sizing respectively on the rolled piece after rolling mill mill rolling in step (5) Rolling by sizing unit, in order to ensure product quality, water-cooled controlled cooling is carried out before and after rolling in the pre-finishing rolling unit, finishing rolling unit and reducing and sizing unit, and rolling is carried out at low temperature and high pressure in the reducing and sizing unit. The rolling temperature is 700℃～950℃, and the running speed of the rolled piece is 5m/s～120.0m/s during the rolling process; in addition, the online roll gap adjustment is configured in the reducing and sizing unit, and the production is controlled by the online roll gap adjustment method The impact of roll wear on product size accuracy, and the caliper at the end of the stand gives real-time feedback on the size of the rolled piece, and realizes real-time fine-tuning of the roll gap; the single adjustment amount of the online roll gap adjustment is less than the size tolerance range before and after the specification change or the user's size Tolerance requirements.

(7) Silk-laying machine spinning: the wire rod rolled by the reducing and sizing unit in step (6) is controlled and cooled to spin silk into loops, and the spinning temperature is 700 ° C to 1000 ° C;

(8) Air-cooled line cooling, coil collection and PF line cooling: Air-cooling or thermal insulation controlled cooling is performed on the wire after spinning in step (7), and after coil collection, PF line cooling and collection is performed.

Example 4

Referring to Fig. 4 and Fig. 5, according to the present invention, the production process sequence includes: continuous casting by continuous casting machine, heating by heating furnace, rolling by rough rolling unit, cutting head and flying shear, welding of intermediate blank connecting device, rolling by intermediate rolling unit , Rolling by the pre-finishing mill, rolling by the finishing mill, spinning by the laying machine, cooling by the air-cooled line, coiling by the core stand, and cooling by the PF line. The process is as follows:

(1) Continuous casting: Multi-machine multi-strand or single-click multi-strand continuous casting machines are used to produce billets or rectangular billets, and the cross-section of continuous casting billets is 150mm×150mm～180mm×180mm or equal-area rectangular billets;

(2) The continuous casting slab in step (1) is heated and kept in a walking beam heating furnace, and the heating temperature is 950°C to 1300°C;

(3) Rough rolling unit rolling: the square billet heated in step (2) is rolled by the rough rolling unit for 6 passes without grooves, and for the rectangular billet, it is rolled for 5 passes. Pass or 7-pass rough rolling unit rolling without holes, and flying shears are installed behind the rough rolling unit. The speed is 0.15m/s～2.00m/s;

(4) Welding of the intermediate billet connecting device: After the front block of the intermediate billet is cut head and tail by the rough rolling mill, the intermediate billet connecting device and its tail run synchronously. After the distance between the rolled piece and the middle billet of the front block is 20-100mm, the rotating friction welding piece or the linear friction welding piece is used to perform rapid linear or rotational friction on the tail of the rolled piece of the front middle billet and the head of the rolled piece of the rear middle billet synchronously, When the temperature of the welding surface reaches 950 ℃ ~ 1050 ℃, carry out upsetting welding. The unit upsetting force is 30MPa ~ 100MPa. After the connection is completed, remove the edge burrs, starting from the catch-up of the rolled piece in the middle of the rear block, until the burrs are removed Finished, the total time is less than 20s; then the rear intermediate billet connecting device moves to the initial position, and the subsequent connecting process of the rear intermediate billet rolled piece is carried out.

(5) Rolling in the middle rolling group: the billet connected in step (4) is rolled in the middle rolling group, the bite temperature of the middle rolling group is 850°C to 1000°C, and the rolling speed during the rolling process is 0.2m/ s～6.0m/s;

(6) pre-finishing rolling group, finishing rolling group rolling: carry out pre-finishing rolling group rolling, finishing rolling group rolling respectively to the rolled piece after the rolling group rolling in the step (5), in order to guarantee product quality The pre-finishing rolling unit and the finishing rolling unit are cooled by water cooling before and after, and the finishing rolling unit is rolled at low temperature and under high pressure. The rolling temperature is 700℃～950℃, and the running speed of the rolled piece is 5m/s～120.0m/s during the rolling process; in addition, the online roll gap adjustment is configured in the finishing rolling unit, and the rolls are controlled by the online roll gap adjustment method during production. The impact of wear on the dimensional accuracy of the product, and the caliper at the end of the stand will feed back the size of the rolled piece in real time, and realize the real-time micro-adjustment of the roll gap; the single adjustment amount of the online roll gap adjustment is less than the size tolerance range before and after the specification change or the user's size tolerance Require.

(7) Silk-laying machine spinning: the wire rod rolled by the finish rolling unit in step (6) is controlled and cooled to spin silk into loops, and the spinning temperature is 700 ° C to 1000 ° C;

(8) Air-cooled line cooling, coil collection and PF line cooling: Air-cooling or thermal insulation controlled cooling is performed on the wire after spinning in step (7), and after coil collection, PF line cooling and collection is performed.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (8)

1. A long material endless rolling connection method is characterized in that, the front block middle billet rolled piece and the rear block middle billet rolled piece are connected by friction welding head to tail welding after passing through the rough rolling unit continuously, and between the two The welding position shall be deburred from the edge. 2. The long material endless rolling connection method according to claim 1, characterized in that, before the friction welding welding, the head and the tail of the front block middle billet are cut by the rear cutting flying shear of the rough rolling unit And cut the head of the rear middle billet, and make the rear middle billet catch up with the front middle billet until the two are synchronized. 3. The endless rolling connection method for long products according to claim 2, characterized in that the total time is less than 20s from the start of catching up with the rear middle billet to the end of burr removal. 4. The long material endless rolling connection method according to any one of claims 1-3, characterized in that, during friction welding, the welded surface of the rear block middle billet and the front block middle billet The temperature reaches 950℃～1050℃, and the welding is completed by applying upsetting pressure; the friction welding method is linear friction or rotating friction, and the upsetting pressure is 30MPa～100MPa. 5. An endless rolling production line for long products, comprising a continuous casting machine (1), a heating furnace (2), a rough rolling unit (3), a cutting head flying shear (4), and an intermediate rolling unit (5) arranged in sequence , finishing rolling unit (7) and collection unit (10), described collection unit is any one in cooling bed, coil collection system or wire rod collection system, it is characterized in that, also comprises intermediate billet connecting device (11), is set After the cutting flying shear and before the intermediate rolling group, it is used to realize the endless rolling connection method described in any one of claims 1-4, including a clamping mechanism, a friction mechanism, a burr removal mechanism (116), a transmission mechanism (117) and upsetting mechanism (118), and the clamping mechanism includes a rear clamping piece (111) for clamping the middle billet (A) of the rear block and a rear clamping piece (111) for clamping the middle billet (A) of the front block ( B) the front clip (112), the friction mechanism includes a supporting part (113), a moving part (114) and a friction head (115), the supporting part is arranged on the moving part, the friction head is arranged on the supporting part, and the transmission The mechanism acts on the friction head, and the upsetting mechanism acts on the rear clamp. 6. The endless rolling production line for long products according to claim 5, characterized in that, the endless rolling production line also includes a reducing and sizing unit (8) after the finishing rolling unit; or the endless rolling unit The production line also includes setting a pre-finishing unit (6) before the finishing unit and setting a laying head unit (9) behind the finishing unit; or the endless rolling production line also includes setting a pre-finishing unit before the finishing unit. The rolling group (6) and the reducing and sizing group (8) and the laying head group (9) are arranged successively after the finishing rolling group. 7. The long product endless rolling production line according to claim 6, characterized in that the rough rolling unit adopts no-hole rolling, and the rough rolling unit and the intermediate rolling unit adopt head-off rolling. 8. The long product endless rolling production line according to claim 7, characterized in that the finishing rolling unit or the reducing and sizing unit is equipped with an online roll gap adjustment device.