On April 19, 2017, Transneft Diascan upgraded 20-DKK combined magnetic ultrasonic in-line defectoscope. The work was done in the scope of the company’s Technical Upgrading Programme from 2014 to 2020. The upgraded device passed acceptance testing and was released for operation by a committee of Transneft.
   20-DKK combined magnetic ultrasonic in-line defectoscope is intended for inspection of 20.87 inches pipes using the ultrasonic (WM, CDL and CDS) and magnetic (MFL) measuring system. The following performance parameters were improved in upgrading the inspection device:

   * resolution of the measuring system was improved by more than twofold increase in the number of WM ultrasonic sensors;
   * minimum dimensions of the detectable pipe wall defects (scratch marks) were reduced by 2.5 times in terms of the width and 1.5 times by the depth (from 0.98 to 0.39 inches and from 0.059 to 0.039 inches, respectively);
   * power consumption of the electronic equipment was halved.

   The combined magnetic ultrasonic in-line defectoscope is regarded as the flagship device in the range of in-line inspection tools independently developed and manufactured by the company. Transneft Diascan was the first in the world to propose merging two major in-line inspection methods – the ultrasonic (WM and CD) and magnetic (MFL) – in the same device. Such a combination enables to effectively unite the benefits of both methods, since defects that are barely noticeable in the use of one physical principle (for instance, the ultrasonic one), are generally easily recognized in the application of the other (magnetic method), and vice versa. Combining the two methods enables maximum sensitivity of the in-line inspection device to discover defects in a single run.