Testing and Inspection
Rigorous testing and inspection ensures that all United States Steel products meet or exceed performance expectations.
United States Steel’s commitment to customer satisfaction includes thorough testing, inspection and certification of all of our products. Our qualified and highly skilled technicians employ a broad array of standard and advanced testing technology to monitor our tubular products every step of the way, from the mill to the well bore. Tests range from laboratory analysis of chemical and mechanical properties, metallurgy, and dimensional measurements, to surface integrity nondestructive tests (NDT) and final product performance testing.
Destructive and Nondestructive Testing
The high standards of the American Petroleum Institute (API) are among the many important industry standards that U. S. Steel Tubular Products must meet. Our tubular products are frequently used in harsh environments where corrosion is an ongoing issue. By using API testing standards as a design requirement, we formulate steel chemistry and metallurgy to handle the most demanding field conditions. Tests of steel samples fall into two categories: destructive (DT) and nondestructive (NDT).
Nondestructive Testing uses noninvasive techniques such as visual observation, electromagnetic tests and ultrasonic inspection to ensure the integrity and reliability of our tubular products. Destructive testing pushes specimens to the point of failure by subjecting them to the forces of axial load, collapse, impact, and environmental corrosion and cracking. The tests reveal the maximum limits of strength and endurance of a particular steel grade and establish safe minimum performance levels.
Testing for Quality
U. S. Steel Tubular Products tests our steel for many reasons: to confirm dimensional conformance, sort materials, locate imperfections, and evaluate any imperfections in light of specifications. Factors that affect yield strength include steel grade, the thermal and mechanical history of the steel, test conditions, and specimen preparation.
U. S. Steel Tubular Products regularly tests:
Tensile strength - the maximum stress or load the material can withstand before fracturing.
Hardness - the material’s resistance to deformation, particularly penetration by a harder surface.
Hardenability - the ability of the steel to harden during rapid cooling (quenching).
Ductility - the measure of the ability of the steel to deform plastically without fracturing.
Fracture Toughness - the ability of a material containing a crack to resist fracture.