CONSOLIDATION, COMMUNICATION, CONTROL

On A Roll: To melt and roll 90 tons of steel an hour, this mini-mill uses an advanced manufacturing execution system that effectively manages the myriad of diverse PLCs distributed throughout its rolling and melting mills.

Gerdau Ameristeel Corporation (Tampa, FL) is the second largest mini-mill steel producer and steel recycler in North America, with an annual manufacturing capacity of more than 10 million metric tons of mill finished steel products. The company currently has 11 mini-mills running a manufacturing execution system (MES) called QMOS and Kepware that interfaces to the company ERP system (Oracle).

While QMOS oversees the management of information to the ERP system, it relies heavily on KepServerEX from Kepware Technologies (Portland, ME) to manage the myriad of diverse PLCs distributed throughout the mills. Currently there are three more mills are scheduled to come online almost immediately and the remainder in the near future. “We have a ton of different PLCs, just about every platform out there . . . Seimens, Allen Bradley, GE, etc. We’re trying to become more standardized, but each mini-mill has its own set of PLCs. The great advantage of using KepServerEX is that its drivers are able to connect to all the PLCs, regardless of their individual specifications,” said Jason McGill, an application architect at Gerdau Ameristeel.

In the company’s Jacksonville, FL, mill there are two major operations, the rolling mill and the melting mill. There is also a shredder that takes large objects such as cars and other large pieces of metal and shreds them down so they will melt faster. To determine the output of the mill, the rule of thumb is that there this about one ton of steel in an average car. The plant melts and rolls about 90 tons of steel an hour. So basically the Jacksonville operation is melting and rolling about 90 cars per hour.

According to Jarrod Parrotta, an improvement facilitator at the Jacksonville plant, Gerdau Ameristeel was utilizing KepServerEX to tie into GE PLCs with another automation system and was pleased when they switched to QMOS that they could still use Kepware because of its interoperability with their MES, SCADA and PLCs. “When QMOS came into play,” explains Parrotta, “we replaced everything with Kepware. This rolling mill operation is monitoring approximately 13,000 I/O points and the melt shop has another 10,000 points for a total of 23,000 I/Os being acquired from the PLCs via KepServerEX. And we’re only about half of where we want to be. Our target is somewhere between 40,000 to 50,000 I/O points.”

Currently the Jacksonville plant uses four Wonderware Servers, two in the rolling mill and two in the melting mill. They are set up in a redundant configuration and running a thin client. The plant will eventually use Factory Focus, Wonderware’s read-only version of InTouch. The thin clients are installed at the corporate side on the desktops of certain executives who have a need for a more granular view of specific operational information.

Process data is collected by KepServerEX via LinkMaster, which allows Gerdau staff to easily link data from multiple data sources and provides a simple means of integrating systems from multiple vendors into a single operational solution. In this case the KepServerEX communicates the data to QMOS and to Factory Focus. “With the current system configuration, I will never have to let anything through the Firewall. Using the two Kepware servers across the Firewall allows me to provide a security control feature and limit the amount of traffic on the process network,” notes Parrotta.