In this paper we present Nondestructive Testing (NDT) systems and instruments used in steel industry for the quality control of production processes. We real-time multi-channel ultrasonic inspection systems with advanced array transducers for the inspection of bars and other semi-finished parts. The equipment is designed for fast inspection in the production flow. For the control of heavy parts we discuss mobile high energy Betatron radio-graphy that can be upgraded to tomography. The control of special processes like surface hardening can also be performed nondestructively based on the evaluation of ultrasonic backscattering. Thermoelectric phenomena are applied for sorting of mixed-up metal parts
