Topic 21 RAIL TESTING USFD Testing of Rail

Topic – 21 RAIL TESTING

USFD Testing of Rail 18: 43 § Rail testing by ultrasonic method shall be carried out by RDSO approved Single Rail Testing Trolley (SRT) or Double Rail Testing (DRT) Trolley and Test rig with 45° probes. § Water is used as couplant while testing with SRT/DRTs. § Soft grease to RDSO Specification no. WD-17 - MISC. -92 or WD -24 Misc. – 2004 / any thick oil of high viscosity grade (having viscosity grade of 150 cst or more) is to be used as couplant while deploying 45° probes with test rig for testing rail.

Details of Probes used 18: 43 Type Frequency Normal 00 No. of probes SRT DRT Rig 4 MHz One for each rail - 700 (centre) 2 MHz Two (F+B) for each rail - 700 (Gauge Face) 2 MHz Two (F+B) for each rail - 700 (Nongauge Face) 2 MHz Two (F+B) for each rail - 450 (Rig Testing) 2 MHz - - Two

Different Steps to be followed 18: 43 § Ultrasonic testing of rails is broadly divided in the following Steps: A. Visual Inspection of equipment & accessories - Daily check B. Calibration of equipment : • The range calibration in SRT/DRT with multiplexure/ multichannel to be done Once in week. • 300/200 mm longitudinal wave for 0° Double crystal Probe. • 165 mm shear wave calibration for 70° (2 MHz) single crystal probe.

Different Steps to be followed 18: 43 C. Sensitivity setting of the equipment and probes : - Check once in every 3 days. D. Checking of equipment characteristics : - Once in a Month. • The characteristics of the equipment shall be checked at least once in a month according to IS : 12666 – 88. E. Testing and Interpretation : • After sensitivity setting , actual testing of rails is to be carried out and interpreted for follow up actions.

Required Accessories 18: 43 1. Digital Rail Tester USFD Equipment with Trolley 2. 0˚ Normal Probe, 4 mhz (Double Crystal) 3. 70˚ Angle Probe (Double Angle Probe) 4. Standard Test Piece with Artificial Flaws 5. Water for Couplant

Standard Test Piece for sensitivity setting of Rail Testing 18: 43 5 mm Ø Flat Bottom Hole 70˚ 25 m m 12 mm Ø Through Hole 15 mm 70˚ 20 mm

Standard Test Piece of Rail 18: 43

Housing to fix the Test Piece 18: 43 Aluminium / Wooden Housing to fix the Standard Test Piece.

Housing to fix the Test Piece 18: 43

Checking the function and sensitivity of probes 18: 43 § Normal Probe : The back wall echo make 100% of full screen height and shall be taken as reference echo. § Angle probe 70° (center forward & backward) : The echo of 12 mm Ø hole in the head portion of the standard rail shall be set 60% of screen height. § While testing on single line and ‘D’ marked rails, addition gain of 10 d. B is to be deployed.

Checking the function and sensitivity of probes 18: 43 § Gauge Face and Non-gauge Face Corner probe 70° (forward and backward) : The echo of 5 mm flat bottom hole make 60% of full height. § 45° probe (for locations having scabs/wheel burns): Machine shall be calibrated for 165 mm for shear wave. The test rig shall be placed at 20 mm below rail table on the side of rail head. The transmitter and receiver probe in the test rig shall be in opposite direction and shall be apart twice the rail head width. Peak obtained in receiver probe make 100% of full screen height.

Testing of Rail 18: 43 § Rail Testing is carried out as per the stipulated frequency for the route. § Along with through Rail testing, special track components like SEJ, Turnout etc. and other locations like wheel burn scabbed rail locations are also to be tested as per the specified frequency and. § After detecting the defect, marking on it and corresponding action to be taken.