The smart factory at HCE Ulsan plant lays the groundwork for the Global One Factory and drives the digitalization of the production of construction equipment
A smart factory refers to a factory where the entire process, including the assembly, production and shipping of products is done automatically, optimized in real-time by analyzing operational and equipment data. With the convergence of information and communication technology (ICT), the entire process can be monitored and analyzed in real-time, while productivity, quality and customer satisfaction can be improved. Therefore, the smart factory is the future of factories and a key element in Industry 4.0.
However, unlike other manufacturing factories, HCE produces tens to hundreds of tons of heavy equipment. This makes it difficult to transform the entire process into a smart factory. Despite these difficulties, HCE Ulsan plant has taken the lead in creating smart factories in the construction equipment sector since 2018. It drew up strategies and achieved Level 1 of enabling a smart factory.
HCE is pushing ahead with a phased construction of a smart factory as the means to innovate production and become one of the top five professional construction equipment makers in the world. Manufacturing costs are continuously rising due to the rise in labor costs and restrictions on working hours. In an effort to improve its competitiveness in production cost, it had to significantly enhance productivity by deploying more robots for each factory line. It also aimed to introduce a smart production system throughout the process in response to the changing paradigm towards a multi-product, small-volume production system and the shift to smart factories in the era of Industry 4.0. It was also important to build a production environment that customers can rely on by making massive investments in infrastructure to replace aging facilities and to support global sales to intensify its promotional efforts in the growing international construction machinery market.
Ok-gyu Jung, deputy general manager of production technology and smart factory strategy in the Production technology department who joined the company back in 2006, says the company has completed Level 1 of enabling a smart factory. This means that the real-time data regarding operation of major facilities, material records and quality are combined based on manufacturing execution system (MES), and visualized in an intuitive format for viewers to monitor. By 2023, HCE will achieve Level 2 with the ability to analyze data for improvement in operational efficiency and reliability of process. In 2025, it will reach Level 3 as a global autonomous smart factory that enables automatic optimization of factories worldwide based on digital twins and data. In Level 3 the company will operate all factories in Korea and abroad using automation facilities and ICT.
HCE is embarking on its journey to embrace the smart factory at Ulsan. The Ulsan smart factory consists of the production line, assembly line and material management areas. The production and assembly areas introduced automated robots, while the materials area introduced a material record management system with barcode and automated guided vehicles (AGVs) to significantly improve productivity with the same number of workers and reduce human errors occurring from repetitive work. The plant also advanced the company wide MES that incorporates cutting-edge ICT convergence technologies such as IoT, big data, and AI. This not only enables the plant to manage and monitor the output per model, machine status, and product quality data, but also separately manage machine failures and maintenance history to improve agility when tackling issues, thereby improving overall facility efficiency.
Building on improved production competitiveness with smart factories, HCE will smoothly respond to the demand for construction equipment that has skyrocketed since 4Q 2020.
[Production Line] Level 3.5 welding automation to provide sufficient supply for the revitalization of construction equipment
The Ulsan production line adopted welding robots to reach Level 3.5, an intermediate level between Level 3 and 4 which means partial automation and complete automation, respectively. Welding robot currently accounts for about 83% of the total welding work at the Ulsan plant, which is considered very high. By 2024, HCE aims to expand welding automation up to approximately 93%. Pros of using welding robot are that it performs tandem welding where it uses two torches. This enables it to handle twice the number of welding compared to the existing method. A large portion of the welding process that used to be done by workers is replaced by robots, speeding up production cycles and increasing the number of products that can be manufactured in the same period of time.
The factory operators, for their part, are monitoring operation data from welding robots and making preemptive actions to prevent machine failures.
Taking this a step further, the Ulsan manufacturing plant is building an integrated welding management system called Hi-Weld and implemented and applied automated technology that detects defects in robot welding in July 2021. This will prevent welding defects in real-time, allow operators to manage via comparison welding records and inspection data, identify the defect causes and build a solution system to minimize rework.
Jung said, “Welding robots dropped the defect ratio in the production line and boosted the number of equipment units a single worker can manufacture. We will set up a new system that prevents the current/voltage problems of manual welding machines and further improve our quality and cost competitiveness.”
[Assembly Line] Achieving Level 3 automation despite volatile manual tasks
The assembly line reached Level 3, partial automation, and achieved a remarkable degree of automation in the operation process for torque, robot and fueling facilities. Compared to car assembly, there are many types of volatile work that require manual work, such as wiring and plumbing. This calls for extremely advanced technology to assign these irregular tasks to robots. Only 5% of the entire process is completely automated at Ulsan, however the plant plans to adopt automatic assembly routes and achieve 31% assembly automation.
Material & equipment history management
The assembly line produces about 30 finished products a day. The material and equipment history management system based on real-time locating systems (RTLS) enables users to accurately measure and track material and equipment locations even in such a complex environment.
The RTLS-based material history management system tracks the location of process models, materials and equipment using RTLS tags that are attached on them in 30 processes where hundreds of excavators are assembled.
Production management
MES provide visual data of material/equipment location, drawings, modeling and their quality in real-time connecting to kiosks in each process.
Deputy general manager Kim, who has 14 years of experience in production management, spoke about MES-based production management, saying “We deployed MES starting in 2018. It collects almost all the data in the assembly line on equipment, quality and failures. It selects the socket, sets torque value and oil flow and monitors torque quality automatically. Quality issues don’t occur in the MES processes.”
Quality inspections
The Ulsan plant set up a data-based quality management system by adopting a mobile quality inspection system. The system manages inspection targets, inspection results and defect information by model, item and day.
The mobile quality inspection system automates equipment quality inspection tasks normally undertaken by 10 inspectors who check incoming and outgoing products. When you enter measures on the tablet, the quality assessment starts automatically. When the measures satisfy quality standards, the results are automatically saved in the DB, and when defects are found, that information gets separately registered.
Lee from the quality management department explained the advantages of mobile quality inspection and said, “A team of inspectors are each designated to a single equipment unit and conduct quality assessments on multiple units simultaneously. This enhances the efficiency of quality inspections. We use tablets that help us understand different options from other countries using visual data such as drawings. It also allows you to automatically verify equipment assembly, streamlining the whole process. We plan to go beyond using tablets and introduce a wearable quality verification system to further improve usability.”
Ulsan plant built a barcode-based material management system for the material warehouse and expanded it to the warehouse and delivery stages by July 2021.
The system accurately captures the location and quantity of materials in real-time and manages the history of major materials, including engines, in relation to the production process and the follow-up management process. Building on this system, the Ulsan plant is managing history such as which model/unit was equipped with which part by matching major materials and the model/unit number of construction equipment. The plant is also responding to issues related to post-sale maintenance and environmental compliance with agility.
Regarding the effectiveness of introducing these systems, Han of the Material operations department said, “Construction equipment consists of dozens of optional features like buckets and arms and between 1,500 to 2,000 parts, so material management is critical. We are running a barcode-based material management system connected to the RTLS process. This allows us to prepare necessary parts on time for specific equipment production early on and extend uptime, respond faster to defective parts and reinforce our response to important environmental regulations such as exhaust gas.”
Ulsan smart factory acting as an outpost in becoming a global one factory
HCE will apply smart factory facilities and technologies similar to the Ulsan plant on other HCE and OEM plants in Korea, as well as offshore plants in China (Jiangsu), India (Pune) and Brazil. By doing this, we will have set up an integrated production, quality and material management system deployed worldwide.
Under the vision of building a global one factory, HCE will establish a safe autonomous operation system that runs 24/7 based on more precise automation control, strengthen flexible production and quality management systems through cross-border data collaboration and respond to the shifting manufacturing landscape.
The example set by Ulsan plant will act as the standard for digital production and quality management on the path to becoming a global one factory. Ulsan plant has developed and been following a roadmap to expand automation and advance MES for three years from 2021 to 2023.
This year, HCE is applying automation centered around welding robots, assembly and logistics. Next year, the scope of automation will expand in inspection, assembly and painting. In the year after, automation would be further applied to manufacturing, painting, assembly and logistics, for example, on automated jigs, AGVs and pallet standardization.
This year, HCE developed MES to assist operators in monitoring production and assembly lines and comprehensively managing quality and materials at production and shipping sites. Next year, the company will reinforce quality management and step up its automation efforts in material management. In the year after, HCE will establish a globally integrated production, quality and material management system linked to overseas corporate bodies and factories in Korea based on a single MES.
The long-term goal of Ulsan smart factory is to reach Level 4 in automation, automating the entire process, and build an autonomous production and quality management system. In the future, such a system will be gradually replicated in overseas corporate bodies and factories in Korea, completing the smart factory vision of HCE.