ABB solves the problem of off-machine coater automation control, and delivers large-scale paper projects to Sun Paper and Huatai. Each papermaker obtained tailor-made, world-leading technology and equipment, including drive control systems and high-efficiency frequency conversion motors, which not only ensure the smooth and efficient operation of the production lines, but also realize energy savings and emission reduction.
In January this year, ABB completed the commissioning of a PMC800 multi-drive control system in a high-end coated paper project at Huatai Paper. Installed on the mill’s PM8, a machine with an annual production of 700,000 tons, the system met Huatai’s design requirements – it solves the problem of off-machine coating automation control, ensures the smooth and highly efficient operation of the production line, and realizes energy savings and emission reduction.
There are only two off-machine coaters of the same type in China, and each is equipped with ABB drive systems. Commissioned in 2004 and 2005 respectively, each is operating well.
Lin Shuming, head of ABB Pulp and Paper North Asia, said: “It indicates that, by integrating unique innovative technologies, ABB’s customized service model successfully passed the test of China’s high-end paper projects. ”
Optimal utilization of advanced technology
During a recent interview, Chen Linfeng, Sales Director of ABB Pulp & Paper China, said that ABB tailored the drive control system PMC800 installed on Huatai’s PM8 according to customer requirements and specific application needs. The drive system on Huatai’s PM8 and coating machine is by far one of the most complicated drive systems used today in the paper industry. The system includes 223 drive sections, 241 AC frequency conversion motors and 10 AC800M controllers ,as well as additional control equipment. It provides AC drive and control for specific parts of the production line, including the paper machine, rewinder, off-machine coater, super calendar and winder.
In China, along with Huatai’s PM8, there are two other production lines with large off-machine coaters. These lines are located at the APP Dagang and Sun Paper.
Production lines of this type are commissioned at the average rate of one every three years. So far, there are several dozen such production lines in the world. The difficulty lies in the control of the off-machine coater, particularly the flying splice control. While the off-machine coater operates at a designated speed, this control method is applied so that online roll-changing can proceed without shutdowns.
Meeting this challenge requires drive equipment that has control precision down to a millisecond level (1-10 ms), along with extensive cooperation and experience between the drive supplier and equipment supplier. Because ABB meet these key requirements, it executes most similar drives projects worldwide.
At Huatai, there are numerous tension control points on the production line. When the speed on the production line varies, it is very difficult to precisely control the tension. The maximum speed of PM8’s coater is 2100 meter/min, which is the extreme speed of the machine and motor. But ABB’s leading drive control technology ensures the production line will operate smoothly and continuously even under such high speeds. This prevents the waste of items such as paper and paint that occur when the coater shuts down, and it also saves the additional labor, water and electricity needed to clean the coater..
To minimize energy consumption, ABB installed customized motors with optimization design on various parts of Huatai’s production line, including the winder, rewinder, super calendar and coater. This kind of motor is much smaller and lighter than standard motors. Its design is optimized according to a piece of equipment’s specific load requirements, so that control and efficiency are optimized. But the overload multiples are high enough to prevent high energy-consumption “light load drives”.
The current installed power of paper machines in China’s paper industry is dramatically higher than it was in the past. This renders the 400V motor, which was previously prevalent, unable to meet new industrial demands. As a result, ABB promotes its 690V grade low voltage motor – the ABB M3BP is the most high-efficiency AC motor in the industry. It is the first batch of motors to obtain China’s authentication of energy-saving product, with an efficiency level of IE2. So far, these new motors have been used in new projects at mills that include the APP Dagang mill, Lee Man Paper, and Huatai Paper.
“It has higher voltage than the 400V motor, so there is less heat loss due to smaller current, contributing to energy-saving,” said Linfeng. The efficiency of ABB’s standard motor is 3.8% higher than that of a normal motor. On Huatai’s PM8 production line with total installed power estimated to be 390,000 kW, this motor can annually save nearly 5 million yuan in electricity costs and almost 3700 tons of coal, a very outstanding amount.
Problem-solving with the world’s best combined service resources
In terms of technology, PM8 is the most complex paper machine in China - or even the world. So ABB selected its best global service team to ensure the project’s smooth implementation. During project execution, ABB Finland sent its principal engineers to meticulously oversee the software and equipment design work, key technology, project progress, etc. They worked with a Chinese team consisting of highly-skilled engineers who are experts in different aspects of the automation. These Chinese specialists could fully utilize local service and equipment manufacturing systems to provide Huatai with the most efficient and high-quality service possible.
Said Linfeng: “Engineers from ABB Finland and China cooperated by contributing their strengths and advantages, which overcame many technical difficulties, accomplished the project meeting its schedule, quality and quantity requirements, and achieved customer satisfaction.” In the past, projects at APP Dagang were usually accomplished by ABB’s European engineers. Now a Chinese local service team dominates the PM8 project.
Linfeng added: “Currently, the most challenging and state of the art paper equipment and projects in the world can be seen in China. The transition from participation roles to leadership roles indicates that ABB China’s local team is gradually growing up. Such localized customized service leads to the formation of long-term strategic cooperation and partnerships between ABB and its China customers. ABB has many customers similar to Huatai, such as, Sun Paper, Lee Man Paper, APP, HengAn, Nine Dragons Paper and Shan Ying Paper. ABB finds the best cooperation points with these customers, and establishes long-term partnerships. HengAn Paper has 15 paper machines, and ABB provided drive control systems and integrated automation control systems for 14 of them. The automation and electrification equipment of 16 paper machines and 3 pulp mills of Lee Man Paper all come from ABB. This is due to the tailor-made service, which provides a very cost-competitive plan.”
Shuming said: “The paper industry is a high energy consumption industry. ABB’s automation technology could significantly help customers improve energy efficiency, and realize green environmental production and sustainable development. Shandong Huatai Corporation is a world-leading paper enterprise. The long-lasting cooperation between ABB and Huatai demonstrates the mutual trust between the two partners, raising excellent cooperation model and energy-saving example for the industry.”