When China’s linen industry goes through digital transformation-- Kingdom realizes lean management with digitalized factory
In textile industry, linen is the segment that has to address such challenges as small industry size, high-labor intensity and outdated equipments.
Clothing made with linen has been very popular for its natural origin and healthy property. Featuring distinctive coarse elegance, linen is a fabric woven with fibers from the flax plant, originating from Europe. Once a booming industry in Europe, the linen business gradually transferred from the West to the East sine the 1960s to escape the sharp rise of labor cost. In Zhejiang and Jiangsu, two Chinese provinces well-known for their numerous rivers and lakes, the linen industry has been flourishing, adding new vigor to its heritage extension.
With a humble beginning as a silk maker in Zhejiang, Kingdom Holdings Ltd., has grown its business to become a linen leader today. In its development process, the company was stifled by increasing manufacturing cost and stagnated yield.
“In textile industry, linen is the segment that has to address such challenges as small industry size, high-labor intensity and obsolete equipments,” said Shen Yueming, Executive Director and General Manager of Kingdom. “To survive, we must reduce labor to lower costs, and improve productivity. So, we turned to Siemens to pave the way of automation and digitization.”
While rising manufacturing cost and stagnated yield pose the external pressure, Kingdom’s sense of responsibility to take the low-end linen industry to a new level in terms of automation, digitization and informatization was the more important internal motivator. Facing a crossroad, the company was in an urgent need to find a way to transform the traditional rustic industry into a modern stylish one. Siemens is undoubtedly the biggest supporter throughout the stormy journey of transformation.
At the new factory, the drying process is to put the wet yarns into the dryers to remove excess moisture.
Kingdom started its factory renovation with an energy management project a few years ago. It awarded the project to Siemens because of Siemens’ strong brand and reputation. After working with Siemens, Kingdom was even more impressed with Siemens’ proven expertise and sense of responsibility through a boiler control system renovation, which made for a coal saving of 15% and an electricity reduction of 26%.
With the positive working relationship, Kingdom decided to engage Siemens in its industrial upgrading and digital factory building as well. In early 2013, a team of Siemens consultants assigned to Kingdom’s linen factories to conduct strategic planning, identified two major problems there.
The first problem was that the production lines were operating in a “black box”. On the surface, everything was appeared to be in order, but there was no system to collect pertinent information about production plan such as consumption of raw materials, production progress or order intake.
In such a “black box”, any equipment failure or repeated/belated repair might affect operation efficiency or even slow down normal production. More importantly, it was impossible to trace data on material, quality or sales.
The second problem was a lack of proper documentation and filing system. Some key production information such as quality data were arbitrarily written in paper slips and not filed for future reference. Such sloppy practice caused confusion and even disputes during month end when the HR department calculates performance commission or bonus. HR personnel end up depending on such slips of written evidence or mere oral reports.
After identifying the two problem areas, Siemens prescribed a scientific solution in the form of production line automation and management transparency. Meticulously designed, the experts decided to start pay-as-you-go deployment of a Manufacturing Execution System (MES) at Kingdom’s old factory in Henggang Zhejiang.
Siemens helped Kingdom identify five management modules.
The MES, an IT-enabled manufacturing management system for the executive level of a manufacturing enterprise, can strengthen execution of material requirements planning (MRP) and link MRP to the control system of the workshop site. The key to that is the management module for individual sections. Therefore, the Siemens experts’ top priority at the old factory was to fully understand the entire linen production cycle to provide customized solutions to each section.
But they encountered a big challenge in their very first step. Linen production should in principle, comply with specifications. However in Kingdom, the production was dominated by human experience. An example was identification of proportions of raw materials for blending. Raw materials, which are from farmlands of Belgium, France or China’s Xinjiang, vary in properties depending on the batches. For a product of a particular specification, the person in charge of blending had to identify, based on personal experience, the right proportion of raw materials by observing their color and texture. This resulted in randomness and non-standardization, which made MES impractical.
“If you are in a mess at the source, traceability will be meaningless,” said Shen Yifei, Head of Quality Assurance and Safety Department and coordinator of Digital Factory Project at Kingdom. Shen has a profound understanding in this regard. As suggested by Siemens, Kingdom purchased professional test instruments which can accurately test physical properties of raw materials. Soon after, the blender found that all raw materials could be divided into six grades and raw materials in different grades could be combined into more than three standard formulas. Test results could be provided directly for the MES, so that the Procurement Department could clearly divide raw materials to facilitate orderly execution of production plans.
Thus, the problem in identification of proportions of raw materials, the headache for the whole textile industry, was successfully resolved. After more than a year of effort, Siemens helped Kingdom identify five management modules, including plan management, quality management, equipment management, material management and job management. These modules cover more than 50 business processes, corresponding to 56 key function points.
These management modules are the core of standardization of production and construction of the MES. The Siemens MES is fully compliant with ISA-95. It is able to reduce costs of integration with the ERP and work with the product lifecycle management software to provide production capacity and status information.
During the implementation of the MES, those who face the toughest challenges are the frontline operators, who have to acclimatize to the modern equipments.
On the road to digitalizing the factory, more problems emerged.
Firstly, at the old factory, the equipments were outdated, mostly without data acquisition system. This makes production transparency totally impossible.
Siemens upgraded some of the equipments, making them capable of digital acquisition with sensors and industrial communication network. The lower-level equipment data were connected to the MES, setting the stage for bottom-up flow of information within the factory.
Secondly, it was hard to acclimatize the frontline operators to the modern equipments. Most of the operators were elderly workers with habits formed over 20-30 years ago.
Siemens experts organized many training sessions for the frontline workers to adapt to the new system. Engineers also changed the system interface and operation mode, turning most of the input operations into simple and efficient QR code scanning.
In short, the engineers tackled every problem they saw and encountered. During the test run of the MES, the factory recorded significant improvements in both productivity and management efficiency.
As for material management, the new system is able to tell at any time the raw materials that are available and those that are running out of stock, thereby improving resource utilization and flow of WIP.
With respect to production planning, all production data are stored in the MES in a well-organized manner. The system interface clearly shows production progress, order intake and backlog. If the management asks for data, the only thing the workers need to do is to click on the mobile APP. Data not only make each production area transparent but also help the management make well-informed and justifiable decisions.
For job management, standardization of business processes makes job management smoother. Eliminating the previous practice – writing field inspection results on paper slips, the management now uses iPad to record data and prints out the rectification list after inspection to make corrections more effective.
As for quality management, products of each specification in each batch should undergo data-based quality inspection. In case of a customer complaint, the management can always trace quality back to an individual batch and production node. It is indeed a qualitative leap in traceability!
For equipment management, with the new module, the system schedules the equipments’ operation and maintenance based on their cycle and status. Thus, it can identify some redundant areas to improve equipment utilization and reduce failure, so as to ensure uninterrupted production.
Apart from upgrading the old factory in Henggang, Kingdom also built a new digital factory in Haiyan, dozens of kilometers away from Henggang.
While upgrading the old factory in Henggang, Kingdom was also building a new digital factory in Haiyan, dozens of kilometers away from Henggang. The Haiyan project was strongly supported by senior consultants of Siemens China Corporate Technology. The consultants hold the conviction that deployment of a digital factory involves not only upgrading of hardware and software technologies, but also perfect integration of production information and automation systems. They also believe that deployment of an enterprise operational process system is the key to digital transformation.
Using Teamcenter that simplifies and accelerates the implementation process, improves productivity and collaboration, the Siemens experts created a virtual factory for full-range simulation of the new facility. This includes IT implementation such as network architecture, field communications, interfaces and equipments, as well as mechanical layout such as EPC, technologies and logistics.
Kingdom’s new factory employed Siemens Sinamics S120 in all of its converters. Siemens’ newly introduced drive control system integrated V/F control, vector control and servo control, for all drives. As a result of its modular design, the system features flexibility and scalability, which allows free combinations of units with different power levels and control performances. The complete drive intelligence is embedded in the Control Units. They handle all of the closed-loop control functions in the drive lineup. They also execute all other drive functions, and have Profibus DP field bus or Industrial Ethernet Profinet as central interfaces to connect to higher-level automation systems. In addition, the new factory introduced energy-efficient motors and retrofitted boilers for scouring, which save about 3 to 5 million yuan in cost every year. All the abovementioned improvements, plus the deployment of an energy management and monitoring system with the B.data software, save the new factory 20% in water consumption and 10% in electricity consumption annually.
Pleased with the overall improvements, General Manager Shen speaks highly of the new system. “As can be seen from the new factory’s plan, our expectations have been met in terms of not only layout and safety but also energy efficiency. The most notable and surprising achievement is in the area of energy efficiency.”
With a staff size of only 1/3 of the old factory yet a very high degree of automation, the new factory can be viewed as a digital factory on the way to “Industry 4.0”.