A guide for a cold rolling three-roll mill
By designing a guide for a cold-rolled three-roll mill and adopting a combination structure of inclined plane and guide wheel, the problem of surface abrasion of steel bars caused by passive rolling was solved, and efficient forming and quality improvement of cold-rolled three-sided ribbed steel bars were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANNAN NANJING STEEL HELI NEW MATERIALS TECHNOLOGY CO LTD
- Filing Date
- 2025-06-05
- Publication Date
- 2026-05-26
AI Technical Summary
In the current production of cold-rolled three-sided ribbed steel bars, there are problems such as surface scratches and substandard transverse rib height caused by passive rolling. This is especially true when producing straight steel bars, which require straightening mechanisms, thus affecting product quality.
A guide for a cold rolling three-roll mill is designed, including a base, a guide cylinder, an outer cylinder, and an inner cylinder. Through a combination structure of inclined plane, spring seat, and guide wheel, an active guiding function is achieved to ensure that the steel bars are accurately introduced before the forming mill.
This effectively avoids scratches on the surface of the reinforcing bars, ensures the forming quality of the three-sided ribbed reinforcing bars, meets the requirements of the new national standard, and improves production efficiency and product qualification rate.
Smart Images
Figure CN224272724U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to steel bar production equipment, and in particular to a guide for a cold rolling three-roll mill, belonging to the technical field of cold rolling equipment. Background Technology
[0002] The new national standard GB13788-2024 for cold-rolled ribbed steel bars was released and implemented in September 2024. The new standard limits the shape of CRB550 products to three-sided ribbed steel bars. Prior to this, some three-sided ribbed cold-rolled ribbed steel bar products on the market were produced using passive rolling. The three-roll mill no longer had a main drive system; instead, traction rollers were installed upstream of the mill. The steel bar was wound several times on the traction rollers, and the driving force generated by the friction of the traction rollers pulled the steel bar, thus achieving passive rolling. The passive three-roll mill structure is relatively simple, with the two stages (reduction and forming) very close together. Even without guide rollers, the correct position of the reduced-diameter steel bar during forming rolling can be ensured. Therefore, the reduction mill in the front stage also acts as a guide. However, the passive rolling process also has its inherent drawbacks. Since the steel bar must pass through the traction rollers after forming, it also needs to be straightened by a straightening mechanism when producing straight steel bars. These two processes inevitably generate strong friction on the outer circle of the reinforcing bar, especially abrading the transverse ribs, ultimately causing surface scratches or even substandard transverse rib height, resulting in quality that does not meet standards. Therefore, the scientific production process for three-sided ribbed products still uses an active forming mill. This requires a guide mechanism before the forming mill. The cross-section of the product after the three-sided ribbed reducing mill is approximately triangular. When the forming mill is an active mill, the semi-finished product with the triangular cross-section needs to be guided into the forming mill rolls to obtain a qualified product. There are many mill guides currently used in reinforcing bar production, but mill guides applicable to the production of cold-rolled three-sided ribbed cold-rolled reinforcing bars are rare. Summary of the Invention
[0003] The purpose of this invention is to provide a guide before the forming mill for the production of cold-rolled three-sided ribbed steel bars.
[0004] To achieve the purpose of this utility model, the following technical solution is adopted: a cold rolling three-roll mill guide includes a base, on which a guide cylinder is fixedly connected or integrally arranged. An outer cylinder is slidably arranged inside the guide cylinder, and an inner cylinder is slidably arranged inside the outer cylinder. Both ends of the inner cylinder extend out of the outer cylinder, and the outlet end of the inner cylinder is a flared mouth. Three spring seat holes are uniformly machined circumferentially on the outer periphery of the inner cylinder, and springs are installed in the spring seat holes. Three guide arms are hinged on the circumferential surface of the outlet end of the inner cylinder. The guide arms press on the springs, and guide wheels are rotatably installed at the front ends of the guide arms. After the steel bar exits from the inner cylinder, it passes between the three guide wheels.
[0005] Furthermore, the outer cylinder has three inclined surfaces A at its front, and the inner surfaces of the rear ends of the three guide arms are inclined surfaces B that are adapted to the inclined surfaces A. The inner cylinder has threads machined on the circumferential surface extending from the outer cylinder at its rear end. An annular groove is machined on the circumferential surface of the outer cylinder near its rear end. The retaining ring is rotatably set in the retaining ring groove. A nut is screwed onto the thread at the rear end of the inner cylinder, and the nut is fixedly connected to the retaining ring.
[0006] Furthermore, an axial elongated hole is provided on the guide cylinder wall, and an axially oriented rack is fixedly connected to the outer cylinder wall. The rack protrudes from the elongated hole, and a gear is rotatably installed on the rack, meshing with the rack.
[0007] Furthermore, an axial keyway is provided on the inner wall of the outer cylinder, and a guide key is fixedly connected to the outer wall of the inner cylinder, with the guide key located in the keyway.
[0008] Furthermore, a set screw hole is machined on the guide cylinder, and a set screw is screwed into the set screw hole to lock the outer cylinder and the guide cylinder together.
[0009] The positive and beneficial technical effects of this utility model are as follows: the three guide wheels of this guide can be opened to allow the steel bar to pass through, and after passing through, the guide wheels are pressed against the surface of the steel bar by the action of two inclined surfaces to achieve guidance. Attached Figure Description
[0010] Figure 1 This is a cross-sectional view of the front and rear directions of this utility model.
[0011] Figure 2 This is a rear view schematic diagram of the present invention.
[0012] Figure 3 yes Figure 1 A schematic diagram of the cross-section along the AA direction. Detailed Implementation
[0013] To more fully explain the implementation of this utility model, implementation examples are provided. These implementation examples are merely illustrative of this utility model and do not limit its scope.
[0014] The present invention will be further explained in detail with reference to the accompanying drawings, in which the following references are made: 1: base; 2: guide cylinder; 3: outer cylinder; 4: inner cylinder; 6: guide arm; 7: spring; 8: inclined plane A; 9: inclined plane B; 10: guide wheel; 11: guide key; 12: rack; 13: set screw; 14: retaining ring; 15: nut; 16: gear; 17: flared mouth.
[0015] In this invention, inclined plane A can be replaced by conical surface A. If inclined plane A is a conical surface A, then inclined plane B is also a conical surface B.
[0016] As shown in the attached figure, a guide for a cold rolling three-roll mill includes a base 1. A guide cylinder 2 is fixedly connected to or integrally formed on the base. An outer cylinder 3 is slidably fitted inside the guide cylinder. A set screw hole is machined on the guide cylinder, and a set screw 12 is screwed into the set screw hole to lock the outer cylinder and the guide cylinder together. An axial elongated hole is opened on the wall of the guide cylinder. An axially oriented rack 11 is fixedly connected to the wall of the outer cylinder. The rack protrudes from the elongated hole, and a gear 15 is rotatably installed on the rack. The gear meshes with the rack. After the set screw is released, the front and rear positions of the outer cylinder can be adjusted by rotating the gear.
[0017] An inner cylinder 3 is slidably disposed inside the outer cylinder 2. An axial keyway is provided on the inner wall of the outer cylinder, and a guide key 10 is fixedly connected to the outer wall of the inner cylinder, with the guide key located in the keyway.
[0018] Both ends of the inner cylinder extend beyond the outer cylinder. The outlet end of the inner cylinder is a flared mouth 16, defined as the front. Three spring seat holes are uniformly machined circumferentially around the outer periphery of the inner cylinder. Springs 6 are installed in the spring seat holes. Three guide arms 6 are hinged to the circumferential surface of the outlet end of the inner cylinder. The guide arms press on the springs. Guide wheels 19 are rotatably mounted on the front ends of the guide arms. The reinforcing bar passes through the three guide wheels after exiting the inner cylinder. The front part of the outer cylinder has three inclined surfaces A7. The inner surface of the rear end of the three guide arms is an inclined surface B8 that corresponds to the inclined surface A. Threads are machined on the circumferential surface of the rear end of the inner cylinder extending beyond the outer cylinder. An annular groove is machined on the circumferential surface of the outer cylinder near the rear end. A retaining ring 13 is rotatably set in the retaining ring groove. A nut 14 is screwed onto the thread at the rear end of the inner cylinder. The nut is fixedly connected to the retaining ring. The retaining ring is limited along the axial direction of the outer cylinder. Rotating the nut can drive the inner cylinder to move relative to the outer cylinder along the axial direction, which can adjust the opening size between the three guide wheels.
[0019] This guide is installed in front of the forming mill in cold rolling. The forming mill is an active mill. When in use, first rotate the nut to increase the gap between inclined plane A and inclined plane B. At this time, the opening between the three guide wheels can be increased to allow the steel bar to pass through smoothly. The steel bar enters from the rear end, exits from the flared end, and then passes between the three guide wheels to enter the forming mill. Then rotate the nut to make the three guide wheels contact the three sides of the reduced diameter steel bar, thus achieving the guiding function. The spring can play a supporting and buffering role.
[0020] After a detailed description of the embodiments of this utility model, those skilled in the art will clearly understand that various changes and modifications can be made without departing from the scope and spirit of the above-mentioned patent applications. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this utility model shall fall within the scope of the technical solution of this utility model, and this utility model is not limited to the embodiments of the examples given in the specification.
Claims
1. A guide for a three-high cold rolling mill comprising a base, characterised in that: The base is fixedly connected to or integrally provided with a guide cylinder. The outer cylinder is slidably fitted inside the guide cylinder, and the inner cylinder is slidably installed inside the outer cylinder. Both ends of the inner cylinder extend out of the outer cylinder. The outlet end of the inner cylinder is a flared mouth. Three spring seat holes are evenly machined circumferentially on the outer periphery of the inner cylinder. The springs are installed in the spring seat holes. Three guide arms are hinged to the circumferential surface of the outlet end of the inner cylinder. The guide arms press on the springs. The front end of the guide arms is rotatably mounted with a guide wheel. The steel bar passes through the three guide wheels after exiting the inner cylinder.
2. A guide for a three-high cold rolling mill according to claim 1, characterized in that: The outer cylinder has three inclined surfaces A at its front. The inner surfaces of the rear ends of the three guide arms are inclined surfaces B that are adapted to the inclined surfaces A. The inner cylinder has threads machined on the circumferential surface extending from the outer cylinder at its rear end. An annular groove is machined on the circumferential surface of the outer cylinder near the rear end. The retaining ring is rotatably set in the retaining ring groove. A nut is screwed onto the thread at the rear end of the inner cylinder and is fixedly connected to the retaining ring.
3. A guide for a cold rolling three-roll mill according to claim 1, characterized in that: An axial elongated hole is provided on the guide cylinder wall, and an axial rack is fixedly connected to the outer cylinder wall. The rack protrudes from the elongated hole, and a gear is rotatably installed on the rack, meshing with the rack.
4. A guide for a cold rolling three-roll mill according to claim 1, characterized in that: An axial keyway is provided on the inner wall of the outer cylinder, and a guide key is fixedly connected to the outer wall of the inner cylinder, with the guide key located in the keyway.
5. A guide for a cold rolling three-roll mill according to claim 1, characterized in that: The guide cylinder has a set screw hole, and a set screw is screwed into the set screw hole to lock the outer cylinder and the guide cylinder together.