Digital Systems Support Electrical Steel Manufacturing at Hunan Hongwang

Translated from the Chinese article dated 14 February 2024. Production figures and forecasts below refer to the period covered by that report.

On 8 February, the reporter visited Hunan Hongwang New Materials Technology Co., Ltd. in the Louxing Industrial Development Zone in Loudi. Lanterns, red couplets and festive decorations marked the approaching Lunar New Year.

Inside the non-oriented electrical steel workshop, the normalizing and pickling line was operating automatically. Steel coils passed through pickling tanks, rinsing tanks and drying equipment. Live video transmitted over a 5G network showed the same operations to staff in the centralized control centre.

Operators monitored loading, pickling, cold rolling, annealing and coating from a control centre equipped with 168 electronic screens, following the production process through to finished electrical steel.

Automation across the production process

Electrical steel, often described in the Chinese industry as the “jewel in the crown of steel,” requires complex processing and tight process control. The report describes Hongwang's smart manufacturing plant as designed for annual production of 960,000 tonnes of high-magnetic-induction grain-oriented and high-grade non-oriented electrical steel. The company said it was building the plant to lighthouse-factory standards; the article does not establish formal lighthouse-factory recognition.

According to the report, automated equipment follows software instructions for production, transfer, process control and performance testing, from raw materials to finished products. Deputy general manager for production Deng Weiquan said the digital systems had helped reduce production costs while improving efficiency and product quality.

A six-stand tandem rolling line

The reporter saw five workers on a six-stand tandem rolling line more than 300 metres long. Deng said that, apart from manual quality checks at uncoiling, welding and recoiling, operators controlled the other processes remotely from the control room.

The line's reported annual rolling capacity was 700,000 tonnes. Compared with a single rolling mill, the company reported an almost fivefold increase in annual rolling capacity, a reduction in labour requirements of at least 70%, and a 90% reduction in losses at coil heads and tails. These are comparisons reported for this installation.

MES, APS and production traceability

The company also developed and used MES and APS management systems. Production planning, quality management, warehousing, logistics and manufacturing data were integrated into a shared view to support lifecycle tracking and detailed process control.

Previously, each coil travelled with an information card. A lost card could lead to mixed coil numbers, mixed steel grades or weight discrepancies. Deng said the cloud management platform made it possible to track materials from receipt to finished-product dispatch, retain records and trace production history when investigating a problem.

In one example, technician Luo Senyuan noticed a red alert in the decarburization annealing section indicating a strip break at the tail of a coil. He reviewed earlier process records and temperature and speed curves. The investigation identified an abnormal normalizing temperature that had affected local strip properties and caused a problem in a later process. The company then used its data analysis functions to adjust process parameters and prevent further quality abnormalities.

Applications and reported production plans

The plant's products serve new-energy vehicles, household appliances and electrical applications. The article also reports production of Hunan's first grain-oriented electrical steel at the site.

Automated cranes moved coils into the finished-products warehouse while trucks queued for loading. Deng said orders for non-oriented electrical steel alone totalled 30,000 tonnes in February. At the time of the report, the company expected to produce more than 600,000 tonnes of electrical steel during 2024, with annual output value approaching RMB 5 billion. These were forecasts reported in 2024, rather than confirmed current results.