Ongoing Research Page 2

Providing Advanced Instrumentation for Process/Product Improvements

Research implemented a new hot mill gauging technology on the Sparrows Point 68” Hot Strip Mill that uses both X-ray and infrared sensors to provide full-width thickness, width and temperature profiles of strip as it exits the finishing mill. The gauge output data supported mill start-up and continue to support process/product improvement on the mill.

High-Strength, Hot-Rolled Sheet for Wheels and Door Impact Beams

Special grades and processing practices have been developed for these demanding segments of the automotive market.

For wheel rim and disc applications, we have developed high-strength, hot-rolled steels with superior forming and welding characteristics combined with excellent surface quality.

Door impact beams (DIB's) are steel components used to reinforce doors to meet DOT side impact protection standards. In many cars, these DIB's are heat-treated tubes made from a Cr-B hot-rolled steel. Compositions were designed to achieve a tensile strength level of 215 ksi after heat treatment, while still meeting special drop weight and bend tests.

Installation of On-Line Setup System at Lackawanna

Research and Lackawanna personnel installed a mill speed set-up display system on the 75” Cold Tandem Mill (CTM) to establish consistent rolling practices, while maximizing a quality product throughout. Operators can preset the mill using the recommended set-ups. Lackawanna plans to use the system to facilitate training of new operators. The system provides the operator with two screens: the first one displays the product and the recommended set-up information for the current coil and the second one displays side-by-side bar-plots of key set-up information and actual

real-time rolling information. Comparison bar-graphs of the stand speeds, strip thicknesses, mill motor loads, and strip tensions are shown. Feedback is provided to the operator on the actual mill set-points used as compared with the recommended mill set-points. Potential problems such as motor current overloading are highlighted to the operator.

Improving the Scheduling of Burns Harbor's Hot-Dip Coating Line

An improved sequencing logic for the scheduling system of Burns Harbor's Hot-Dip Coating Line has significantly improved productivity by reducing gaps in the schedule.

A gap is caused by changes in coil width, cross-section or furnace cycle temperature that the line cannot handle. Gaps are filled by inserting “dummy coils” in the production schedule between bona fide coil orders. The improved sequencing logic resulted in a reduction of 15% in the number of gaps.

Qualification Testing for Burns Harbor's Hot-Dip Coating Line

The hot-dip galvanizing/galvannealing line at Burns Harbor is a key part of Bethlehem's strategy to be a premier supplier of coated sheet to the automotive industry.

Automotive customers require significant testing of new products or products from a new facility before they will begin to purchase them. Tests typically include base metal properties, metallic coating properties, corrosion performance, weldability and formability testing. Customers also require stamping trials at their plant to further demonstrate satisfactory performance of the material. Research was assigned the task of conducting the extensive qualification testing for all products from the new Burns Harbor galvanizing line for supplier approval.

Qualification testing has paved the way for the Burns Harbor hot-dip galvanize/galvanneal facility to serve the needs of General Motors, Ford and Chrysler.

Reducing blistering of Electrogalvanized Sheet

Electrogalvanized (EG) Sheet produced at our Walbridge facility has been a key product component of Bethlehem's strategic response to the automotive demand for exposed-quality coated steel. The product was exhibiting blistering of the zinc coating in customers' assembly plants and in paint bake simulation in Walbridge's Quality Control laboratory. A Research/Burns Harbor task force was formed and, through extensive experimentation, it was discovered that rolling fluids trapped in microscopic flaps on the steel surface, created during the cold-rolling process, caused the zinc blistering. The team identified several opportunities to fine-tune operating practices at the tandem mill and box anneal to eliminate blistering. As a result, internal rejections at Walbridge dropped dramatically and the blistering problem in customer plants has been virtually eliminated.

Creating a New Temperature Measuring System for Galvanneal Processing

A study of the galvannealing process showed that carefully controlling the strip temperature profile through the galvanneal furnace is essential for providing a consistent, high-quality product.Research developed and built a new type of radiation pyrometer that can measure the temperature of products having variable thermal emissivity during the alloying process. The devices have helped Lackawanna to significantly improve sheet temperature control thereby improving product quality.

Eliminating Surface Scratching of Tin Mill Products

Two-piece Drawn & Iron (D&I) food cans represent an important and growing market segment for Sparrows Point's tin mill products. A D&I can maker was experiencing excessive die wear and surface scratches due to metal buildup from Sparrows Point's tin plate product. Working with the Tin Mill, Research identified the cause of the problem and new surface finishing practices were developed to enhance the manufacturing performance. The metal buildup problem was eliminated — paving the way for Sparrows Point to double its shipments of D&I material to this important customer the following year.

Advanced In-Line Head Hardening of Rail

To meet railroad demands for high hardness “premium” rail, Pennsylvania Steel Technologies recently commissioned a new in-line head hardening process. Research provided extensive technical support in achieving the desired metallurgical characteristics in the new product.