KR-20260063243-A - STEEL SURFACE INSPECTION DEVICE

KR20260063243AKR 20260063243 AKR20260063243 AKR 20260063243AKR-20260063243-A

Abstract

A steel surface inspection device according to one embodiment of the present invention comprises: an image acquisition unit for acquiring a surface image of a steel moving in a moving direction; a defect detection module for detecting defects in the surface image of the steel using an object detection model; a coordinate calculation module for calculating the location coordinates of the detected defects and indicating the measurement coordinates of a laser sensor; a laser sensor unit for moving in the width direction of the steel and measuring the size and depth of the defects based on the measurement coordinates; and a determination module for determining whether the steel passes or fails using the size and depth of the measured defects.

Inventors

배철현
이재희
김범철

Assignees

에이치디한국조선해양 주식회사
에이치디현대중공업 주식회사
에이치디현대삼호 주식회사

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (7)

An image acquisition unit for acquiring a surface image of a steel material moving in the direction of travel; A defect detection module that detects defects in a surface image of the steel using an object detection model; A coordinate calculation module that calculates the location coordinates of the detected defect and indicates the measurement coordinates of the laser sensor; A laser sensor unit that moves in the width direction of the steel and measures the size and depth of the defect based on the measurement coordinates; and A determination module comprising determining whether the steel material passes or fails using the size and depth of the defect measured above. Steel surface inspection device.
In paragraph 1, The above coordinate calculation module is A configuration for calculating the measurement coordinates of the laser sensor using at least one of the moving speed of the steel material, the distance between the image acquisition unit and the laser sensor, and the real-time coordinates of the defect. Steel surface inspection device.
In paragraph 1, The above judgment module is A method for determining the steel material as unsuitable when at least one of the following is true: the size of the defect is greater than or equal to a set size, the depth of the defect is greater than or equal to a set depth, or the density of the defect is greater than or equal to a set density. Steel surface inspection device.
In paragraph 1, If the width of the steel is greater than the measurable width of the laser sensor, the steel is divided into multiple regions. Steel surface inspection device.
In paragraph 4, The above steel material is divided into a first region and a second region in the longitudinal direction, and The above laser sensor unit A first laser sensor for measuring the first area; and A second laser sensor for measuring the second area, Steel surface inspection device.
In paragraph 1, A lighting unit further comprising a lighting unit that irradiates lighting light to form an acute angle with the surface of the steel, Steel surface inspection device.
In paragraph 1, The above lighting unit Upper lighting for illuminating the upper surface of the above steel material; and It includes a bottom light that illuminates the lower surface of the above steel material, The above image acquisition unit An upper camera for acquiring an image of the upper surface of the steel, and including a lower camera for acquiring an image of the lower surface of the steel, Steel surface inspection device.

Description

Steel Surface Inspection Device The present invention relates to a steel surface inspection device for inspecting surface defects of steel. At shipyards, steel plates used for shipbuilding (hot-rolled steel, cold-rolled steel, thick plates, etc.) are stored in the steel storage yard and then retrieved for pretreatment when needed. Surface defects can occur due to the ingress of foreign substances during the rolling process or corrosion caused by prolonged external exposure. During the pretreatment process, most surface defects are eliminated through shot blasting and primer coating, but some deep defects remain on the surface even after pretreatment. If such surface defects are discovered in subsequent processes after all pretreatment is complete, finishing work is required to remove them, resulting in unnecessary work requirements and process delays; therefore, it is necessary to detect them early to improve productivity. Conventionally, workers inspect defects in steel materials visually and illuminate the upper surface with a portable lantern, but inspection of the lower surface is virtually impossible due to the lack of a turn-over process for inspection. Furthermore, as inspection work is conducted based on the workers' experience, discrepancies in inspection results occur among workers; objectivity is lacking because clear standard normal and defective data are not established; and it is difficult to accurately identify defects on the surface of the steel material. FIG. 1 is a block diagram showing a steel surface inspection system according to one embodiment of the present disclosure. FIG. 2 is a schematic diagram showing the side view of a steel surface inspection device according to one embodiment of the present disclosure. FIG. 3 is a schematic diagram showing a steel surface inspection device according to one embodiment of the present disclosure from a top view. FIG. 4 is a drawing for explaining surface defects of steel according to one embodiment of the present disclosure. FIG. 5 is a drawing for explaining defects recognized in a surface image of a steel material according to one embodiment of the present disclosure. FIG. 6 is a flowchart of a steel surface inspection method according to one embodiment of the present disclosure. The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. Terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and/or" includes a combination of a plurality of related described items or any of a plurality of related described items. Terms such as "~part," "~section," "~part," etc. may be used to describe various components, but said components should not be limited by said terms. These terms may refer not only to physically or visibly distinguishable components but also to descriptions of the function or configuration of a relevant part, even if the distinction or division is not clearly defined. The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to specify the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application. In the description below, terms related to direction such as "front," "rear," "side," "front," "back," "up and down," "top," "upper," "top," "bottom," "lower," "bottom," and "left and right" are defined based on the vehicle or vehicle body. Furthermore, while terms s