KR20210086780A - Method for Evaluating Skill of FCAW Welding Trainee and Apparatus thereof - Google Patents

Abstract

The present invention relates to an FCAW welding trainee proficiency evaluation method and device for effectively evaluating the FCAW welding trainee's proficiency by measuring work variables of a FCAW welder. The FCAW welding trainee proficiency evaluation device according to an embodiment of the present invention comprises: a side camera disposed on the side of a welding part to photograph a welding side part to measure a welding speed, a torch height, and a travel angle; a front camera disposed in front of the welding part to photograph the welding front part to measure a working angle and a torch height; and a control unit that receives an image from a side camera to measure a welding speed, a torch height, and a traveling angle, and receives an image from the front camera to measure a working angle and a torch height. It is possible to numericalize the fluctuation characteristics of working variables including a torch height, welding speed, working angle, and travel angle. By grading the proficiency of a welder, the proficiency of FCAW welding trainees can be evaluated.

Description

FCAW Welding Trainee Proficiency Assessment Method and Apparatus {Method for Evaluating Skill of FCAW Welding Trainee and Apparatus thereof}

The present invention relates to a method and apparatus for evaluating the proficiency of an FCAW welding trainee, and more particularly, to a method and apparatus for evaluating the proficiency of an FCAW welding trainee so that the proficiency of an FCAW welding trainee can be effectively evaluated by measuring the work variables of the FCAW welder.

FCAW (Flux Cored Arc Welding) is mostly done by semi-automatic welding, and in Korea, FCAW welders are most active in workshops such as shipyards. In general, the evaluation of the welder's skill level is performed by considering the appearance of the bead and the degree of defects after welding, and also through a mechanical test. However, the level of welding quality actually obtained in the field is determined by the fluctuating characteristics of work variables that depend on the skill of the welder.

Therefore, in the case of trainees in the welding training process, a simple and economical evaluation system is required to evaluate their proficiency by measuring work variables. In addition, in the process of grading the proficiency of trainees, it is required to more rationally measure the operation of the actual welder to evaluate the proficiency. If the variable characteristics of the work variables are scored and fed back to the trainees, the trainees will be more interested and be able to focus on improving their proficiency.

In consideration of this point, an object of the present invention is to provide an FCAW welding trainee proficiency evaluation method and apparatus for effectively evaluating the FCAW welding trainee's proficiency by measuring the working variables of the FCAW welder.

FCAW welding trainee proficiency evaluation apparatus according to an embodiment of the present invention, a side camera disposed on the side of the welding portion to photograph the welding side portion to measure the welding speed, the torch height, and the travel angle; a front camera disposed in front of the welding part to photograph the welding front part to measure the working angle and the torch height; and a control unit for receiving an image from the side camera to measure a welding speed, a torch height, and a traveling angle, and receiving an image from the front camera to measure a working angle and a torch height, the torch height, welding speed, and operation The proficiency of FCAW welding trainees can be evaluated by quantifying the variation characteristics of work variables including angles and travel angles and grading the proficiency of welders.

FCAW welding trainee proficiency evaluation method according to an embodiment of the present invention comprises the steps of: photographing the welding side by a side camera disposed on the side of the welding;

photographing the welding front by a front camera disposed on the front of the welding; receiving an image of the welding side portion and calculating a welding speed, a torch height, and a travel angle; receiving an image of the welding front part and calculating a working angle and a torch height; digitizing the fluctuation characteristics of working variables including the torch height, welding speed, working angle, and travel angle; And by grading the skill of the welder may include the step of evaluating the skill level of the FCAW welding trainee.

According to the present invention, it is possible to effectively evaluate the skill level of the FCAW welding trainee by measuring the working parameters of the FCAW welder.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the detailed description of the present invention, so the present invention is limited only to the matters described in those drawings and should not be interpreted.
1 is a diagram schematically illustrating an arrangement of welding cameras.
2 is a view schematically illustrating a measurement of the size of a welding specimen.
3 is a diagram schematically illustrating a welding situation measured by a side camera.
4 is a diagram schematically illustrating a welding situation measured by a front camera.
5 is a graph showing the fluctuation of the torch height when welders A and B perform straight-line welding.
6 is a graph showing the fluctuation of the torch height when welders C and D perform weaving welding.
7 is a graph showing the variation of welding speed when welders A and B perform straight-line welding.
8 is a graph showing the variation of welding speed when welders C and D perform weaving welding.
9 is a graph showing the variation of the working angle when welders A and B perform straight-line welding.
10 is a graph showing the variation of the working angle when welders C and D perform weaving welding.
11 is a graph showing the variation of the travel angle when welders A and B perform straight-line welding.
12 is a graph showing the variation of the travel angle when welders C and D perform weaving welding.
13 is a view showing the evaluation scores of welders A to D with respect to the average value of the working variable as a cumulative bar graph.
14 is a view showing the evaluation scores of welders A to D with respect to the standard deviation as a cumulative bar graph.
15 is a view showing the sum of evaluation scores of welders A to D as a cumulative bar graph.
16 is a table showing a score distribution table for average values and standard deviations.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. In addition, the embodiments described below do not unreasonably limit the content of the present invention described in the claims, and the entire configuration described in the embodiments of the present invention cannot be said to be essential as a solution for the present invention. Components applied to one embodiment may be applied to other embodiments even if not specifically mentioned.

FCAW welding trainee proficiency evaluation apparatus according to an embodiment of the present invention, a side camera disposed on the side of the welding portion to photograph the welding side portion to measure the welding speed, the torch height, and the travel angle; a front camera disposed in front of the welding part to photograph the welding front part to measure the working angle and the torch height; and a control unit for receiving an image from the side camera to measure a welding speed, a torch height, and a traveling angle, and receiving an image from the front camera to measure a working angle and a torch height, the torch height, welding speed, and operation The proficiency of FCAW welding trainees can be evaluated by quantifying the variation characteristics of work variables including angles and travel angles and grading the proficiency of welders.

FCAW welding trainee proficiency evaluation method according to an embodiment of the present invention comprises the steps of: photographing the welding side by a side camera disposed on the side of the welding;

photographing the welding front by a front camera disposed on the front of the welding; receiving an image of the welding side portion and calculating a welding speed, a torch height, and a travel angle; receiving an image of the welding front part and calculating a working angle and a torch height; digitizing the fluctuation characteristics of working variables including the torch height, welding speed, working angle, and travel angle; And by grading the skill of the welder may include the step of evaluating the skill level of the FCAW welding trainee.

According to the present invention, it is possible to effectively evaluate the skill level of the FCAW welding trainee by measuring the working parameters of the FCAW welder.

The four working variables measured in the present invention are torch height, welding speed, working angle, and travel angle. Variations in these work variables depend on the skill of the welder and are factors that directly affect the welding quality. By quantifying the fluctuations of work variables, which are empirical skills, it can be applied to welder skill evaluation and quality control.

The base material used in the embodiment of the present invention is SM400 of 150 X 100 X 6 mm. _{FCAW CO 2} welding used for welder training was performed by BOP welding in a downward-viewing position for 4 welders, and welders A and B performed straight-line welding, and C and D performed weaving welding. Table 1 shows the welding conditions used in this experiment. Table 1 shows the welding conditions for 1G position FCAW welding.

Filler metal AWS A5.20 E71T-1C 1.2mm base metal SM400 150 X 100 X 6 mm Current 170-230A Voltage 21.6 to 25.4 V

A welding camera arrangement method used in this experiment is shown in FIG. 1 . A camera was placed to photograph the welding side, and the welding speed, torch height, and travel angle (θ _T ) were photographed. _{The working angle (θ W} ) and the torch height were photographed by placing a camera for photographing the welding front part.

In consideration of the distance between the camera and the measurement target, the scale bar was photographed on the welding part using the welding side camera immediately before welding. 2 shows a welding specimen and a scale bar photographed. At this time, in order to measure the torch height, the travel angle (θ _T ), and the welding speed, still images were acquired at intervals of 1 second from the arc start point of the captured image from the welding side part. _{Torch height, travel angle (θ T} ), and welding speed were measured at 1 second intervals using still images and scale bars.

2 shows a step of correcting the position by using a scale bar before welding. This is a step that is carried out in order to correct the error in length caused by the shooting distance and angle by placing the scale bar on the welding part and taking a still image with a camera.

_{3 shows the measurement of the travel angle (θ T} ), the welding speed, and the torch height in the welding side part photographed image. _{4 shows the measurement of the working angle (θ W} ) in the image taken of the front part of the welding. In order to correct the error of the torch height, it was calculated considering the _{working angle (θ W ).}

Table 2 summarizes the mean and standard deviation of the working variables of welders A to D. The average value of the working variable was calculated to evaluate whether it was within the normal working variable range. The standard deviation was calculated to evaluate the fluctuations of the working variables because the fluctuations in the working variables of the welder affect the welding quality.

welder calculation method torch height welding speed working angle angle of advance A medium 26.35 33.9 3.68 34.92 Standard Deviation 1.36 1.95 0.81 0.59 B medium 18.03 39.9 0.78 7.59 Standard Deviation 2.75 2.28 0.99 0.98 C medium 26.35 33.9 3.68 34.92 Standard Deviation 1.36 1.95 0.81 0.59 D medium 18.03 39.9 0.78 7.59 Standard Deviation 2.75 2.28 0.99 0.98

In order to evaluate the proficiency of welders A to D, evaluation scores were given in consideration of the mean and standard deviation of the work variables. In consideration of the importance of work variables affecting the welding quality, the weights of 3 torch height, 2 welding speed, 1 working angle, and 1 traveling angle were assigned to the evaluation score. The torch height was set at 15 mm, and points were deducted as the average value deviates from the standard. Welding speed was deducted as the average value was lower, and in the case of weaving welding, a lower range was applied compared to straight welding. The working angle and advancing angle were set at 0 degrees, and points were deducted as the average value deviates from the standard. The larger the standard deviation of the working variable, the more points were deducted. The mean and standard deviation were considered as the same weight and reflected in the evaluation score. 16 shows a score distribution table for average values and standard deviations. Table 3 is a classification table according to the sum of evaluation scores.

Total score 0-29 30-44 45-59 60-70 Grade 4 3 2 One

13 is a cumulative bar graph showing the evaluation scores of welders A to D with respect to the average value of the working variables. 14 is a cumulative bar graph showing the evaluation scores of welders A to D with respect to the standard deviation. 15 is a cumulative bar graph showing the sum of evaluation scores of welders A to D. Welder D showed the best level with 67 points and was evaluated as Grade 1. Welders C and B were evaluated as Grade 2, the next level, with 55 and 52 points, respectively. Welder A was evaluated as Grade 3 with 40 points. Through these results, it was possible to suggest a method for grading and evaluating welders' proficiency using the fluctuating characteristics of work variables, not welding results, in order to arouse interest in trainees' growth psychology.

The following conclusions can be obtained as a result of an experiment to obtain technical data to provide feedback to trainees by shooting, measuring, and analyzing the characteristics of fluctuations in the four major working variables that were shown by four welders directly performing FCAW. 1) A method of measuring four working variables one per second by recording a welding video by a welder by directly generating an arc using the arc front camera, side camera, and scale was presented. 2) After scoring the mean and standard deviation of each of the work variables with the same weight and evaluating them separately, a system was proposed to give feedback to trainees by classifying the mean and standard deviation for each of the four work variables. 3) Considering the importance influencing welding quality when evaluating proficiency, weights were assigned as 3 torch height, 2 welding speed, 1 working angle, and 1 traveling angle. 4) In order to arouse interest in trainees' growth psychology, proficiency was graded into Grades 1, 2, 3, and 4 using the variable characteristics of work variables, not welding results.

Although described above with reference to the embodiments of the present invention, the present invention is not limited thereto, and various modifications and applications are possible. That is, those skilled in the art will readily understand that many modifications are possible without departing from the gist of the present invention.

Claims (2)

a side camera disposed on the side of the welding part to photograph the welding side part to measure the welding speed, the torch height, and the travel angle;
a front camera disposed in front of the welding part to photograph the welding front part to measure the working angle and the torch height; and
A control unit for receiving an image from the side camera to measure a welding speed, a torch height, and a traveling angle, and receiving an image from the front camera to measure a working angle and a torch height,
FCAW welding trainee proficiency evaluation device for evaluating the skill level of FCAW welding trainees by quantifying the fluctuation characteristics of work variables including the torch height, welding speed, working angle, and traveling angle, and grading the skill level of the welder. photographing the welding side by a side camera disposed on the side of the welding;
photographing the welding front by a front camera disposed on the front of the welding;
receiving an image of the welding side portion and calculating a welding speed, a torch height, and a travel angle;
receiving an image of the welding front part and calculating a working angle and a torch height;
digitizing the fluctuation characteristics of working variables including the torch height, welding speed, working angle, and travel angle; and
FCAW welding trainee proficiency evaluation method comprising the step of evaluating the skill level of the FCAW welding trainee by grading the skill level of the welder.

Images