Almost nine thousand tests have been completed there on an annual basis.
The researchers´ performance also means hundreds of hours spent in laboratories every year. At U. S. Steel Košice we have several such specialist workplaces and each of them specializes in something different. One of them is called the Laboratory for Refractories. The name suggests that this refers to a workplace in which physical properties of materials are tested as they are intended for environments with extremely high temperatures. This mainly concerns various types of refractory bricks, mortars, stemming and filling material.
The laboratory is located in the basement of the AB Building of Refrako Division, near the gasholder for blast furnace gas. “We started building the laboratory in 2002 at the request of the former Refrako,” says Vincent Zajac, Researcher and Developer, speaking about the facility's history. “It took us two years to have it finished and fully equipped with the necessary devices. In 2004 a change in the organization structure resulted in our department transfer to the General Manager Research and Development USSE unit,” he adds.
The laboratory consists of several rooms where various specific apparatus and equipment is placed. For example, in the first one the researchers carry out measurement of geometric dimensions, and they detect weight, volume or porosity of materials. The second one is used for preparation of refractory material which is then fired in kilns located in the third room. In the fourth room tensile strength and compression tests are carried out using a testing press, and in the next room samples of bricks are prepared by sawing or grinding.
According to Vincent Zajac, almost nine thousand tests are completed in the Laboratory for Refractories every year, all of them in compliance with the applicable standards of STN, EN, ISO and DIM. The staff consists of three employees. Vincent Zajac is also responsible for appropriate documentation preparation in accordance with the applicable Safe Job Procedures. The laboratory equipment consists of old as well as new devices. “The latest acquired device enables testing of resistance to read heat, creep strength and thermal expansion of materials. We purchased it last year,” Mr. Zajac clarifies and adds that they are planning expansion of the laboratory. “We have already submitted a request for some new instrumentation to be placed on the first floor of the building.”
The instrumentation should also be enhanced with two new devices in the near future. Such equipment will involve a tube furnace for determining thermogravimetric figures intended for monitoring of weight decrease in refractory materials depending on temperature change, as well as a large-scale furnace for heat treating samples of non-standard size up to the temperature of 1300°C.
The laboratory is used not only for the work of our researchers; however the staff also deal with requirements from other operations of our Company. In some cases, clients of the laboratory are also external companies that carry out contracted activities for U. S. Steel Košice.