Everything You Need to Know About the Fiber Laser Welding Machine

In modern fiber laser welding machines, precision and efficiency are two features every manufacturer looks for. These advanced machines are optimized for speed, accuracy, and durability, making them a critical part of the production process in aerospace, automotive, electronics, and even medical device industries. In this article, you will learn how these machines operate alongside their key strengths and the outstanding technologies that distinguish them from others. Regardless of whether you are familiar with the laser-welding industry or an industry expert, this guide will enable you to tap into the potential of these sophisticated systems and harness the technology that is redefining fiber laser welding standards in the 21st century.

How Does a Fiber Laser Welding Machine Work?

A beam of light is created by an optical fiber and used to join materials in a welding machine. The light is focused on the workpieces, which pose extreme temperatures that result in melting in the welding zone. The melted materials subsequently solidify and bond, forming a precise and durable connection. Because of its precision, Fiber lasers are used in applications with intricacies such as delicate mechanisms. The laser source, focus optics, and control system work together flawlessly to ensure clean, repeatable welding of the highest caliber.

Understanding the Laser Source

The core component responsible for generating the laser beam used in welding action is the laser source. It has a gain medium which is usually a fiber containing rare-earth elements such as ytterbium. It also has a pumping unit which energizes the medium in order to produce light. This light is collected then amplified, and finally emitted as a highly focused beam of exceptional power. The precision with which this light is fired greatly surpasses all previous limitations. The performance and quality of the welds are directly related to the effeciency and stability of the laser source.

The Role of the Laser Beam in Welding

A laser’s most important feature concerning welding is that it can focus energy to a small area at a given time, allowing materials to be both melted and fused, or welded together, meticulously. Even in nuanced or sophisticated procedures, I trust it to create strong, precise welds because of its capability to deliver controllable, high power. The degree to which it calms or reduces disturbance and regions that feel the heat is critical to the overall work, especially in regard to the quality and uniformity in production.

Comparing Traditional Welding Methods with Laser Welding

Various industries have relied on traditional welding techniques, such as MIG, TIG, and stick welding, due to their cost-effectiveness and adaptability. When compared to laser welding, traditional techniques fall short regarding efficiency, precision, and range of application. Laser welding is able to work within tighter tolerances than traditional welding, achieving welds as small as 0.2 mm in width. Unlike other techniques, laser welding is well-suited for work in aerospace, automotive, and electronics industries where micro-welds are essential.

Amongst the various benefits offered by laser welding, having a considerably smaller heat-affected zone (HAZ) than traditional methods is one of its advantages. Having a smaller HAZ leads to reduced thermal distortion, an issue present in MIG or TIG welding. For instance, laser welding can achieve 25 mm penetration depths while retaining structural integrity, making it far superior to weld stainless steel and aluminum without substantial warping.

Laser welding is more efficient, with laser welds reaching speeds greater than three meters per minute, contingent on the beam power and material thickness. Traditional welding approaches are time-consuming, often needing filler materials, augmenting both time and financial expenditure. By adopting laser technologies, industries have reported up to a fifty percent reduction in production time.

When analyzing a system, the upfront cost of traditional welding systems is lower, however the long-term costs are higher due to maintenance and hoses such as electrodes and shielding gas. Consistently more expensive, laser welding systems offer cost-effective maintenance and operational lifespan. Additionally, modern fiber lasers have made laser welders more energy efficient, claiming over thirty percent additional energy savings compared to older welding technologies.

Lastly, laser welding is superior in adaptability to automation compared to traditional methods. It easily interfaces with robotic components, allowing for precise and repeatable operations in large-scale production. Lesser degrees of automation are achievable with MIG or TIG welding, which relies on manual operation and is more labor-intensive.

The differences mentioned above emphasize the advantages of laser welding technology when considering precision, efficiency, and scalability for modern industrial applications. Although some traditional methods may still be suitable for a limited number of specific use cases, an increasing number of industries are adopting laser welding as they focus on productivity and accuracy.

What Are the Technical Parameters of a Laser Welder?

The Importance of Laser Power

Laser power selection in laser welding is of utmost importance because it governs the energy applied to a given material. Adequate power guarantees effective penetration and merging, thus providing optimal strength to the welds. Insufficient power results in weak bonds, while too much power may damage or deform the material. The correct laser power setting is determined while considering the material’s composition, thickness, and rate of welding required, all while maintaining optimal weld efficiency and quality.

Key Specifications of a 1kw and 2kw Laser Welder

Under a 1kw Laser Welder, the following technical characteristics would fit:

• Power Output: 1 Kilowatt (1kw).
• Material Compatibility: Thin material up to 4mm thick includes, stainless steel, mild steel, aluminum and its alloys.
• Welding Speed: During this range: 600 – 1,200 mm/min, depending on the thickness and type of material.
• Beam Quality: Possesses a high focus accuracy which translates to a very small heat affected zone (HAZ).
• Energy Efficiency: Suitable for lightweight applications because of low power consumption, thus making it economical.
• Cooling System: Basic water-cooling or air-cooling.
• Applications: Great for the fabrication of electronics, precise components, and light sheet metal.

Under a 2kw Laser Welder, users will find advanced features like: 

• Power Output: 2,000 watts (2kw).
• Material Compatibility: Works with alloys such as stainless steel, mild steel, and aluminum upto 10mm thick making it ideal for mid-heavy materials.
• Welding Speed: Varies between 800 – 2,400 mm/min depending on material thickness and requirements.
• Beam Quality: High precision performing capabilities and further ability for more depth penetration.
• Energy Efficiency: Compared to a 1kw device, energy efficiency – is mainly used for heavy-duty tasks.
• Cooling System: Advanced water cooling systems are used to control excess heat during continuous workload.
• Applications: Ideal for automobiles, industrial machines, metal structure fabrication as well as other mid and heavy duty metal works.

Both 1kw and 2kw laser welders present distinct advantages based on application needs, material characteristics, and the quality of output desired.

Adjusting the Welding Speed for Optimal Results

Welding speed is a critical parameter that directly impacts the quality and efficiency of the weld. As a rule of thumb, thinner components would require higher speeds while preventing the input of excess heat, which could result in raised distortion. On the other hand, low speeds are vital when working with thicker pieces to ensure sufficient penetration and a reliable weld. Adjusting the speed of a weld provides favorable results in not only enhancing defect-free joints but also in improving the strength of joints, resulting in the removal of undesirable by-products like porosity or undercutting. It is preferable to set the parameters, especially if a test weld is needed prior to final execution.

What is the Welding Process for Fiber Lasers?

Stages of the Welding Process

Preparation

• Proper preparation is important when completing a precise, defect-free weld. It involves cleaning the workpiece surfaces of oil, grease, rust, and other harmful contaminants. For fiber laser welding, precise edge alignment and gap minimization between the two materials result in accurate energy delivery and bond formation during the welding process.

Laser Welding Positioning and Fixturing

• Materials should be clamped and fixtured securely to prevent any form of movement or misalignment during the welding process. Since the laser needs to be focused accurately over the joint, the beam must not deviate from the set path. Thus, the pose tracking for the laser must be accurate and efficient. For this purpose, robotic fixtures or automated positioning systems are used to ensure accuracy, particularly in mass production sessions.

Laser Welding Parameter Calibration

• Adjusting parameters for power density, pulse duration, and beam diameter, among others, is critical if a laser is to perform at peak efficiency. In most cases, thicker materials require higher laser power, while thinner materials are prone to warping if subjected to any decent amount of laser power. For example, fiber laser applications can apply power levels of 500W to 30kW through localized heating.

Laser Welding Procedure 

• In this step, a laser beam is concentrated at the joint where a very hot molten pool is formed ‘above the solidus’ , which subsequently cools to form a rigid and homogenous weld. The welding speed needs to be modified according to the kind and thickness of the material, for instance, when welding aluminum it usually goes at higher speeds as compared to stainless steel due to its thermal conductivity. Sophisticated sensors are available in the market today to automate process monitoring for real-time quality consistency.

Weld Cooling and Inspection

• The structure is integrated during the cooling phase to preserve bound stresses and guarantee effortless weld integrity. With Fiber lasers, the cooling process is simplified as lasers reduces the heating substantially. During the cooling stage, Non – destructive testing using X Ray inspection or ultrasonic inspection systems are conducted to check for internal flaws and validate joint sufficiency.

Removing Excess Material Welds

• Once all inspections are completed, the welds are polished, or the excess welds are ground off at a set sequence of operations designed for optimal polish placement or other float finishing methods. These changes are critical for sectors with a desire for global top standards, like aerospace or surgical tech.

All of these desgined with a single goal of improving fiber laser welding which marks its importance through its versatile implementation in multiple domains.

Why Choose a Handheld Fiber Laser Welding Machine?

A mobile fiber laser welding machine possesses unparalleled versatility and is very easy to operate, making it ideal for a multitude of applications. Its compact design allows for precision welding in difficult-to-reach or intricate areas, solving problems that traditional welding methods are often not able to tackle. Moreover, these devices guarantee high welding speeds and low heat input which results in minimal distortion and enhanced quality of the weld joint. Handheld fiber laser welding devices that utilize lasers feature low maintenance and easy operation, making it an ideal solution for many industries that need flexibility and dependability.

Ensuring Laser Safety During Operations

Adhering to all safety procedures when operating a handheld fiber laser welding machine is crucial to minimize the risks resulting from working with a laser. The use of powerful lasers and dangerous lasers include eye injury, skin burns, and even fire. Because of this, a thorough program on laser safety should be established for operators and people in the vicinity of the laser.

The first step is to design proper PPE for each one of the operators. Most importantly, they should have goggles that are specially designed to prevent the wavelength of the laser in use from reaching the eye. It is well-documented that exposure to dispersed or concentrated laser beams can permanently disable eyesight making certified spectacles a necessity. Appropriate armaments for the operator include gloves and clothing made of materials that can withstand heat and serve as protection against exposure to hot matter or materials.

Second, it is very important to maintain an organized workspace. For those not directly at risk, the laser welding area must contain protective curtains made with laser-absorbing fabric or materials. Provided that there is sufficient enclosing or restriction of the work area, Data clearly shows that the risk of accidentally exposing the area to a laser is significantly reduced.

Compliance with legal regulations such as those issued by OSHA or ANSI Z136 is another important consideration. It is necessary to provide proper training on the correct use, maintenance, and precautions for the equipment so that operators are fully trained on its usage. Also, equipping the machine with an emergency stop control can minimize the chances of mishaps.

Furthermore, the safety of employees is increased with routine servicing and maintenance of the laser welding equipment. The existence of certain broken parts such as protective covers or fiber optics can increase risks as well as decrease performance. Preventive maintenance has been shown statistically to decrease machine incidents up to 30%, which aids maintaining safety and efficiency.

With these protocols in place along with an appropriate culture of safety, it is possible to maximize the effectiveness of handheld fiber laser welding machines while ensuring the safety of workers and minimizing resource waste.

How Does a Laser Welding Head Function?

Components of the Welding Head

Like many systems, the welding head of a laser system is comprised of constituent components, each of which serves an important purpose:

1. Collimating Lens – focuses the converging laser beam unto an incoming path so that it can be further subdivided into parallel strands for easier manipulation.
2. Protective Lens – cuts off parts of the spattering that form during the actual welding so as to prevent damage to the other internal components.
3. Nozzle – supplied with a clean gas which when directed to the area of work, shields the weld against rough combustion while also making sure no impurities are drawn in.
4. Beam Focus Lens – the piece that has the laser beam cut down to the required target area for precision welding deep into the material layers.
5. Cooling System – removes excessive heat generated within the welding head parts. Keeps them at the required superficial temperatures for longevity of services.

The above system components work together to manage the laser beam and make it possible to achieve precise and automatic welding regardless of the industrial setting.

The Laser Head and Its Applications

Due to the accuracy and versatility of the laser head, it is crucial in almost all industrial sectors. Its primary function is laser welding, which used to join various alloys and metals without minimum distortion using a laser head with a welding telescope. In the modern era, most companies use automatic systems to incorporate laser heads into welding telescopes for the automotive, aerospace, and electronics industries.

Another of the most relevant applications includes laser cutting. The laser head can cut through materials such as steel, aluminum, and composites at an unmatched speed while slicing through the material with exceptional edge edginess. Today’s laser cutting devices equipped with advanced laser heads can cut through thin materials at 20-40 m/min with a 0.1 mm kerf, which optimizes material usage.

In the medical field, surgical treatments alongside the manufacturing of medical grade equipment rely heavily on laser heads. For instance, repetitive dynamic tasks such as stent manufacturing require precision focusing lenses offering adjustable micrometer precision that laser heads in conjunction with CNC machines can provide.

Moreover, laser heads are critical components of additive manufacturing or 3D printing. Businesses are able to form intricate components from metal or polymer powders by meticulously “printing” them one layer at a time. This technology allows lighter designs to be created, less material to be wasted, and for production to be scaled up, transforming entire industries in the process.

Adaptive lens coating and real-time cooling lasers are new technologies that improve the efficiency and lifespan of the laser head. The diverse and new demands from other precision industries are being integrated with state-of-the-art technology to expand the use of the laser head.

Advantages of Using a Handheld Laser Welding Head

Enhanced Precision and Control

• The utilization of handheld laser welding heads has given laser welding users unrivaled precision and control over the hand laser welder’s operation, particularly for detailed repairs or complex designs needing accuracy.

Versatility Across Materials

• Such devices can be used for various materials like titanium, carbon steel, stainless steel, and aluminum, meaning handheld laser welding heads can serve various purposes in the aerospace, automotive, and even manufacturing industries.

High-Speed Welding  

• Unlike traditional methods, handheld laser welding heads are capable of welding from 2 to 10 times faster than other techniques, which significantly decreases production timelines. For example, studies show laser welding can reach speeds of 120 inches per minute (IPM), drastically elevating efficiency.

Minimal Heat Affected Zone (HAZ)  

• With regard to the heat affected zone, the use of advanced laser technology minimizes the HAZ which can lead to delicate materials warping or distorting, ensuring quality finishes and improved structural integrity of the welded part.

Reduced Post-Processing Requirements  

• Because of the precise clean welds resulting from handheld laser welding, there is reduced need for extensive grinding or finishing post welds which decreases labor costs and shortens production timelines.

Portability and Flexibility

• Due to the compact and ergonomic configuration of handheld laser welding heads, they can be operated more effortlessly and afford easier access to hard-to-reach areas. This is especially advantageous for on-site repairs or welding within confined spaces.

Advanced Energy Efficiency

• These devices employ less energy than other welding methods, which also lowers operational costs. For instance, laser welding systems often function at efficiencies of up to 25-30%, which is much higher than the arc welding method.

Ease of Use

• Many of the handheld laser welding systems are equipped with user-friendly interfaces and automation systems, therefore greatly reducing system training, which makes teaching unnecessary. Operators need virtually no skills or experience to attain professional-level results.

Advanced Safety Features

• With modern handheld laser welding heads, automatic shutoff, and protective overheating features make the tools extremely safe to use. These innovations increase safety for the operators and workplace safety levels.

Handheld laser welding heads make a significant difference in efficiency, precision, and adaptability. Therefore, they have become an essential apparatus in today’s multi-purpose welding operations throughout many industries.

What Makes Welding Technology Efficient?

Innovations in Welding Techniques

Technology in welding has evolved due to the implementation of new methods which aim at improving operational and efficiency standards. The following are some of the most important advancements:

Welding with Lasers 

• This technique uses very powerful laser beams for cutting, and it welds more accurately and faster than older ways. Because of the reduced distortion, traditional techniques allow slower processing speeds with the welds receiving minimal heat.

Friction Stir Welding (FSW) 

• These join methods are without melting the materials. This results in lower defects and stronger welds which is ideal for lightweight materials such as aluminum.

Integrating Additive Manufacturing 

• Flexibility and ease of designing complex parts is made possible through the combination of 3D printing technologies and welding. This feature enhances the speed at which these parts are produced.

Automated Welding Systems 

• With robotics and artificial intelligence plugged into the machines, welding is done at larger scales with minimal human effort and increased productivity. The quality of the work is consistent and unified.

These developments have encouraged strong practices in welding across industries, offering unparalleled precision, durability, and productivity.

The Impact of Air-Cooled Laser Welding Machines on Efficiency

The development of air-cooled laser welding machines has revolutionized their use in industrial manufacturing by providing new levels of efficiency, reliability, and cost-saving. The laser welding process utilizes an air cooling system that manages heat within the system, which does not require water-based cooling systems. With less circulatory cooling, the need for maintenance is lessened, and air cooling helps avoid corrosion issues.

As compared to water-circulated laser welding machines, air-cooled systems have been found to drastically cut power consumption. Air-cooled systems are also more flexible and reliable. According to industry data, they reduce energy consumption by as much as 30 percent in comparison to water cooled systems, making them an ideal option for manufacturers concerned about minimizing financial and environmental stress.

These machines are also recognized for being reliable in high-volume operations, providing consistent quality throughout the weld. With effective air management, these systems achieve faster cooling cycles which increases throughput and decreases weld interval downtime. For example, more recent developments in air-cooled welding technology demonstrate increased system uptime by a minimum 20% compared to older systems, validated by productivity measurements in the automotive and aerospace industries.

Air-cooled laser welding machines have now been incorporated into automated systems and integrated with Industry 4.0 technologies. Their advanced cooling systems increase compatibility with robotics and IoT devices, allowing for smarter workflows with real-time diagnostics, predictive maintenance, and optimized production scheduling.

The advancement of air-cooled laser welding systems is producing quantifiable results across various sectors. These systems are now considered to be a vital element of modern manufacturing systems. The combination of energy saving, low maintenance needs, and easy integration makes these systems advantageous to companies seeking sustainable and economical solutions to manufacturing.

Precision and Control: Control Over the Welding Process

Through advanced monitoring and feedback systems, air-cooled laser welding systems offer control over the entire welding process. Defects are minimized, and high-quality results are achieved since sensors are integrated, which measure parameters such as temperature, beam alignment, and weld depth. Moreover, software-driven automation permits real-time setting adjustments, which is vital for different materials and complex designs. This precision level enhances product quality while decreasing waste and rework which maximizes overall production efficiency.

Frequently Asked Questions (FAQs)

Q: What is a fiber laser welding machine, and how does it work?

A: A fiber laser welding machine is a sophisticated system that uses lasers to weld metal parts. It works by sending a high-power beam of light through a fiber optic cable, which is focused on the workpieces. The laser energy melts the materials and bonds them together. Thus, strong and precise welds can be achieved more efficiently and faster than with traditional welding techniques that are often more cumbersome and slower, aesthetically unpleasing, and less forgiving on the metal joints.

Q: What are the advantages of using a laser welder machine over traditional welding techniques?

A: There are numerous benefits to using welder laser machines than conventional methods which include recommended economic costs, higher speed, greater precision, and reduced input of energy and heat into the work pieces, which minimizes distortion. The laser welding technique produces cleaner, thinner welds on fragile materials and demands less finishing work after. Furthermore, it diminishes power usage, making it more affordable for specific projects.

Q: What kinds of materials are possible to weld using a fiber laser welder?

A: A fiber laser welder is versatile and can weld various types of materials, including metals like steel, stainless steel, aluminum, copper, and even titanium. Such devices work excellently with dissimilar materials and thin sheets of metals. Because of the control one has over the parameters of laser welding, fiber laser welders are able to join materials that cannot be traditionally welded.

Q: What is a handheld laser welding machine, and what distinguishes it from other stationary systems?

A: Handheld laser welding machines are portable and flexible compared to established systems as they enable ease of movement without constraints to a workshop setting. Unlike stationary systems, handheld laser welders are extremely mobile and thus suitable for fieldwork, maintenance, and welding in cramped and difficult positions. While they do carry lower power outputs than stationary systems, handhelds have a wider range of use in small precision maneuvers, spot welding, and small-scale welding.

Q: What primary features should be considered when using a laser welding system?

A: The system features that need to be taken into consideration include the amount of power the laser is able to produce (1.5kW or 3kW), welding modes (constantly or periodically), system cooling type (air-cools or uses a chiller), micromotor capabilities, and user interface for setting welding parameters. In addition, it focuses on systems with safety mechanisms, flexibility for multiple materials, and provisions for automation or interfacing with other devices. The exact features needed will depend on your welding applications and production scales.

Q: In what ways does fiber laser welding stand out when compared with other types of laser welding?

A: Among all the laser welding technologies out there, fiber laser welding has its own unparalleled perks. Fiber laser tools are more effective than CO2 lasers because they consume less energy, they occupy less space, and they are easier to maintain. Additionally, their beam quality is superior, and they can work with reflective metals much more easily. In comparison with Nd: YAG lasers, fiber lasers are more efficient as they have better beam quality and longer life spans. As a result, these lasers are ideal for industrial applications.

Q: What safety measures should be considered when using a fiber laser welding machine?

A: Safety considerations take first precedence when operating a fiber laser welding machine. Major steps include utilizing the proper class of eye protection relative to the laser used, maintaining ventilation to remove fumes, PPE such as gloves, protective clothing, proper machine guarding, or any other PPE needed, and appropriate ventilation systems. Proper procedures concerning debris and dust shielding should be followed along with receiving training specific to the equipment being operated, adhering to established protocols, and understanding controllable threats of the apparatus, such as reflected laser beams, if applicable. Some systems may require the employment of inert shielding gases such as argon for other welding applications.

Q: In what ways does fiber laser welding increase efficiency in the manufacturing process?

A: The use of fiber laser welding technology proves that there is significant prominence in efficiency concerning operational speeds of manufacturing processes due to factors such as increased speed of welding, lessened heat input, and less post-processing, deeming work efficiency. Additionally, this technoloy facilitates the automation of the fiber laser welding processes, therefore greatly enhancing productivity. The periphery of automation and decreased energy ascent further establish this as a favorable solution concerning welding applications opting to deem it especially in bulk production settings. The precise control of welding parameters allows for the qualitative and quantitative value of scrap cuts. Greater precision also leads to a decrease in the required volume of energy and minimal maintenance of consumables, leading to cost savings.

Reference Sources

1. A New Approach to Evaluating the Laser Welding Quality of Stainless Steel 304 Using Machine Vision and Hidden Markov Models

• Author: Xin Tang et al.
• Published In: IEEE Access 2020
• Summary: This work proposes an approach to defect classification for fiber laser welding using machine vision and HMMs. The authors pay particular attention to the role of keyhole geometry in the assessment of quality and developed an algorithm for the segmentation of the welding images along with keyhole shape extraction using gray projection distribution and the Poisson sewer method. The correlation between keyhole geometry and some weld defects of concern (porosity and penetration) was done using a pre-trained HMM skeleton in the geometry model.
• Key Findings:
• The method allows real-time monitoring of the welding quality.
• The probable defects can be reliably detected, which reduces the need for thorough checks after welding requirements.
• Methodology: The study involved real-time image acquisition during the process of welding, elaborate image processing was done to the images to obtain the geometrical features of the keyhole which were then analyzed using HMM (Tang et al., 2020, pp. 130633–130646).

2. Online Detection Method for Laser Weld Porosity Defects in High Power Fiber Lasers

• Author: Xin Tang et al.
• Published in: 2020
• Summary: This paper describes an online porosity defect detection method for high-power fiber laser welding. The authors emphasize the importance of both keyhole behavior and keyhole stability in the qualitative assessment of welding. They applied real-time imaging to capture the keyhole’s movement and employed adaptive contour thresholding for contour extraction.
• Key Findings:  
• The method achieved a significant level of accuracy in pore defect detection.
• It sheds light on the atypical metal flow patterns that occur during welding, which may cause undue process defects.
• Methodology: The authors captured, processed, and analyzed images of the keyhole frame by frame—turning the grayscale images into binary to simplify classification—and subsequently classifying the images with a support vector machine based on the features selected from the images (Tang et al., 2020, pp. 117170N-117170N-9).

3. A Spectroscopic Approach To Identifying And Classifying Fiber Laser Welding Defects Using Support Vector Machine And Artificial Neural Network

• Authors: Yuanhang Chen et. al
• Published in: NDT & E International, 2019
• Summary: This work implements a spectroscopic approach for fiber laser welding defect detection and classification leveraging Support Vector Machines and Artificial Neural Networks. The authors performed several experiments to evaluate the accuracy of both methods.
• Key Findings:
• Regarding defect classification, both methods demonstrated potential, but SVM accuracy was slightly surpassed by ANN.
• The study validated the method on a test dataset, demonstrating its practicality for real-life applications.
• Methodology: The research consisted of gathering spectroscopic data during the welding operation and then using machine learning methods to classify the spectral data into different types of defects (Chen et al., 2019, p. 102176).

4. Keyhole and Molten Pool Character-based Root Hump Defect Tracking of High Power Fiber Laser Welding Thick Plates

• Authors: D. Huang et al.
• Published in: 2021
• Summary: This paper presents an approach to monitoring root hump defects in high-power fiber laser welding. The authors employed keyhole dominance and molten pool features to monitor the process using image-sensing technology. Machine vision algorithms were appropriate for real-time feature extraction.
• Key Findings:
• A new method for monitoring root hump defects was developed and integrated into the system, which improved accuracy.
•  A relationship between keyhole features and root hump defects was developed and analyzed.
• Methodology: The authors used machine vision for feature analysis of the keyhole and molten pool during the welding process and classification was performed using a BP neural network (Huang et al., 2021).

5. Welding

6. Metal

7. Stainless steel