ANTI-FREEZING CONTACT LIQUID FOR ULTRASONIC FLAW DETECTION OF RAILWAY RAILS Russian patent published in 2021 - IPC G01N29/28 

FIELD: rail transport.

SUBSTANCE: invention relates to the field of non-destructive testing using a couplant which is used in freezing temperatures for flaw detection of railway rails, elements of turnouts and welded joints in railway transport and provides a sliding friction coefficient of at least 0.15 on the rail after applying the couplant and when it completely dries out. Disclosed is a contact fluid for ultrasonic flaw detection of railway rails, elements of turnouts and welded joints at negative temperatures. The contact fluid contains components at the following ratio, wt%: potassium acetic acid grade "Ch" or potassium acetic acid technical, followed by cleaning the solution from mechanical impurities - 43-45, non-metallic abrasive particles with density of less than 1500 kg/m³ based on caprolon, or caprolite, or carbolite, or nylon (polycaprolactam), or nylon, or neoleucorite, or caprolactam, or their mixtures - 5-25, thickener - 0.01-0.02 and the rest is water.

EFFECT: technical result consists in ensuring reliable acoustic contact with the controlled object in wide ranges of operating temperatures up to minus 50-55 °С, ensuring the values of the sliding friction coefficient on the rail after applying the couplant and with its complete drying above 0.15, the possibility of long-term storage of the couplant in the absence of special requirements for storage conditions, as well as the absence of emission of harmful volatile substances during storage.

1 cl, 1 tbl