FEATURES TANDEM

TANDEM

High-speed railroad switches are railway critical objects, subjected to enormous mechanical stresses at aggressive weather conditions. One of the factors ensuring the railroad switches safety is the periodic monitoring of their frogs which includes visual and ultrasonic inspection for absence of internal and surface flaws according to TI 07.47-2005 PA Krestovina 2750 and STO RZD 1.11.007-2009.

Ultrasonic testing is used to detect internal and surface flaws, welding joints for cracks, lack of fusion, blowholes and nonmetallic inclusions, as well as defects such as transverse fissures in a rail head, a web and a base. Tandem is a special tandem carriage for monitoring transverse weld joint chromium-nickel insert from the running surface of rail at the end web using two at 45 ° angle-beam probes according a tandem testing scheme.

Using a Tomographic UD4-TM with a Tandem scanner enables rail scanning with a required increment and record flaw coordinates detected in real time (B-scan visualization of a transverse welding joint in rail web area and its projection into a rail base), that simplifies the data decoding and reduces testing time.

Precision positioning is provided by using high-accurate encoders built in a scanner rotation axises. Application of the Tandem-scanner allows scanning with the required increment and in real time data record and save defect location coordinates, tomographic image display and a defect risk assessment, which significantly increases testing speed while increasing its objectivity and reliability.

Application of Tomographic UD4-TM dual-channel flaw detector with specialized programs and a coordinate scanner makes it possible to increase objectivity and reliability by reducing the human factor influence on the testing results.