Combined working roll of bar mill

Abstract

The utility model discloses a combined working roll of a bar mill. The combined working roll comprises a roll core, positioning rings, a roll sleeve, a spacer sleeve and a locking sleeve, wherein the positioning rings are respectively sleeved on a roll body section of the roll core; the surface of the roll sleeve is provided with a hole-shaped groove; the structure that the roller core and the roller sleeve are combined is adopted, the corresponding roller sleeve can be freely replaced according to changes of production specifications, meanwhile, the roller sleeve can be rapidly replaced when encountering reasons such as abnormal faults, the downtime is shortened gradually, and the roller core can be repeatedly used. Moreover, in the waterless rolling process of the steel grade, the cooling holes of the spacer sleeves can be adjusted by the radian water pipe device of the rolling mill for high-pressure water spraying, so that the water enters the axial cooling grooves and dispersedly flows through the radial cooling grooves, and the roller sleeve is cooled from inside to outside.

Description

Technical Field

[0001] This utility model relates to rolling mill work rolls, and more specifically, to a combined work roll for a bar rolling mill. Background Technology

[0002] Metal bars are a common type of metallurgical product. The production process of hot-rolled metal bars is as follows: steel billets are heated, then hot-deformed in a continuous rolling mill, and hot-rolled into straight bars. Depending on the product application and user requirements, some bars undergo heat treatment or further processing. Therefore, on a metallurgical wire rod hot rolling production line, the rolls on various stands are key components and indispensable rolling elements.

[0003] Currently, the rolls used in hot rolling production lines for wire rods and bars are generally composite rolls made of high-NiCr materials. These rolls are characterized by being cast in one piece using both materials. They suffer from drawbacks such as low throughput per slot, rough working surfaces in the slots, and pitting. Furthermore, high temperatures can sometimes cause metal from the rolled piece to adhere to the rolls, forming periodic indentations and roll marks, affecting the surface quality of the bars. Additionally, during the rolling of anhydrous steel grades, some stands experience severe oxidation and corrosion on the slot surface, leading to a decrease in material hardness at high temperatures, resulting in poor wear resistance and low throughput. This significantly increases the workload for on-site workers, requiring frequent slot and stand changes, impacting hourly operating rates and safe production. Utility Model Content

[0004] In view of the above-mentioned defects in the existing technology, the purpose of this utility model is to provide a combined work roll for bar mills, which can reduce the frequency of slot and roll changing, extend the service life, and improve the production line operation rate.

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

[0006] A combined work roll for a bar mill includes a roll core, and further includes a positioning ring, a roll sleeve with a perforated groove on its surface, a spacer sleeve, and a locking sleeve respectively fitted on the roll body section of the roll core. One end of the roll body section has a first boss, and the inner ring of the positioning ring has a second boss that matches and positions the first boss. Several roll sleeves are spaced between the positioning ring and the locking sleeve and are interference-fitted with the roll core. The spacer sleeves are respectively located between the positioning ring and the roll sleeve, between the roll sleeves, and between the roll sleeve and the locking sleeve and are clearance-fitted with the roll core. The locking sleeve has a locking hole radially provided and is locked and fixed to the roll core by locking bolts.

[0007] The spacer sleeve has several cooling through holes in its radial direction.

[0008] The surface of the roller core has several axial cooling grooves spaced apart.

[0009] The roller core has several circumferential cooling grooves spaced apart on its roller body section surface, and the circumferential cooling grooves are connected to the axial cooling grooves.

[0010] This utility model provides a combined work roll for a bar rolling mill, employing a structure combining a roll core and a roll sleeve. The roll sleeve can be freely replaced according to changes in production specifications. Furthermore, the roll sleeve can be quickly replaced in case of malfunctions, minimizing downtime. The roll core is reusable. In the process of anhydrous rolling of steel grades, high-pressure water can be sprayed from the cooling holes of each spacer sleeve via the mill's arc-shaped water pipe device. This water enters the axial cooling tank and is dispersed through the radial cooling tank, cooling the roll sleeve from the inside out to extend its service life. Attached Figure Description

[0011] Figure 1 This is a three-dimensional structural view of the combined working roller of this utility model;

[0012] Figure 2 This is a cross-sectional view of the combined working roller of this utility model;

[0013] Figure 3 This is a three-dimensional structural view of the roller core of this utility model;

[0014] Figures 4-7 These are perspective views of the positioning sleeve, spacer sleeve, roller sleeve, and locking sleeve of this utility model. Detailed Implementation

[0015] To better understand the above-mentioned technical solution of this utility model, the technical solution of this utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0016] Please combine Figures 1-7 As shown, the combined working roller of this utility model includes a roller core 1, a positioning ring 2 respectively fitted onto the roller body section of the roller core 1, a roller sleeve 4 with a perforated groove 3 on its surface, a spacer sleeve 5, and a locking sleeve 6. The roller body section has a first boss 7 at one end, and the inner ring of the positioning ring 2 has a second boss 8 that matches and positions the first boss 7. When the positioning ring 2 is fitted onto the roller body section, axial positioning is achieved through the cooperation of the two bosses. The roller sleeve is made of a material with high wear resistance, red hardness, and impact resistance, and uniform material hardness (HRC±1). Several roller sleeves 4 are spaced between the positioning ring 2 and the locking sleeve 6, and are installed with the roller core 1 via interference fit heat fitting. Figure 1 As shown, there are three roller sleeves 4, each with three perforated grooves 3. Spacer sleeves 5 are respectively positioned between the positioning ring 2 and the roller sleeve 4, between roller sleeves 4, and between the roller sleeve 4 and the locking sleeve 6, as shown. Figure 1As shown, there are four spacer sleeves 5, which are fitted with the roller core 1 with a clearance fit. The locking sleeve 6 has two radial locking holes 9, which can be locked and fixed to the surface of the roller core 1 by internal hexagonal locking bolts, and axially clamp and fix the roller sleeve 4, spacer sleeve 5 and positioning ring 2.

[0017] Each spacer sleeve 5 is provided with several cooling through holes 10 evenly in the radial direction, and the surface of the roll body section of the roll core 1 is also provided with several axial cooling grooves 11 and several circumferential cooling grooves 12 at intervals. The circumferential cooling grooves 12 are connected to the axial cooling grooves 11 to form a uniformly distributed internal cooling channel.

[0018] During operation, the billet in the furnace is heated to a certain temperature before entering the steel production line. It first enters the primary rolling mill area; then it enters the intermediate and finishing rolling lines equipped with the combined work rolls of this invention. The work roll area is typically equipped with arc-shaped water pipes on the stand to spray water onto the surface of the grooves 3 of the roll sleeves 4 for arc-shaped cooling. If waterless rolling is used (considering the rolling performance of special steel grades and the potential for head blooming leading to steel accumulation and equipment / production accidents), the water pipes are adjusted to the cooling through-holes 10 of the spacer sleeves 5 of the combined rolls for high-pressure water spraying. The cooling water enters the axial cooling tank 11 through the cooling through-holes 10 and flows through the radial cooling tank 12, cooling each roll sleeve 4 from the inside out to ensure that there is no cooling water on the surface of the grooves 3; finally, the hot round steel product exits the last stand and is cut to length and collected on the cooling bed.

[0019] This novel combined work roll increases the steel throughput per groove by 3.5-4.5 times compared to traditional rolls. With sufficient cooling, the groove wear is uniform and smooth, and the single-side grinding amount is halved. It also enables the anhydrous rolling of certain special materials, addressing surface defects such as pitting caused by oxidation and corrosion due to lack of water during thermal transformation and thermal shock in some anhydrous rolled steel grades. This prevents thermal stress cycles that can lead to transverse cracks and bursting. Furthermore, the roll has a simple structure, is easy to install, and highly operable. It solves the problems of low steel throughput, frequent roll and stand changes, and excessive downtime associated with traditional rolls. This improves the efficiency of bar and wire production and reduces the labor intensity of employees.

[0020] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present utility model and are not intended to limit the present utility model. Any changes or modifications to the above embodiments within the scope of the essential spirit of the present utility model will fall within the scope of the claims of the present utility model.

Claims

1. A modular work roll for a rod mill comprising a roll core, characterized by: The positioning ring, the roll sleeve, the spacer sleeve and the locking sleeve are respectively sleeved on the roll body section of the roll core.

2. The combined work roll of a rod mill according to claim 1, characterized in that: The spacer sleeve is radially provided with a plurality of cooling through holes.

3. The combined work roll of a rod mill according to claim 2, characterized in that: The roll body section surface of the roll core is intermittently provided with a plurality of axial cooling grooves.

4. The combined work roll of a rod mill according to claim 2, characterized in that: The roll body section surface of the roll core is intermittently provided with a plurality of circumferential cooling grooves, and the circumferential cooling grooves are communicated with the axial cooling grooves.

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