analyst nd system

Horizon Testing Inc. is pleased to offer the Analyst ND (Near Drum) inspection system to our clients. A computer controlled, automated ultrasonic inspection system, Analyst ND was developed and manufactured specifically for the purpose of providing thickness measurements of tubes on the mud and steam drums of boiler generating banks.


The operating principle of the system is based upon the ultrasonic pulse-echo technique for measuring wall thickness commonly measured by hand-held thickness instruments. A transducer converts a pulse of electrical energy into ultrasonic sound vibration. The pulse is a longitudinal wave, known as a straight beam, which travels perpendicularly through the water to the tube wall. A small part of the energy is transmitted through the tube wall and is reflected off of the back wall, and then back to the transducer.

General Description

The Analyst ND system uses a pulse echo focused transducer that transmits sound waves through the tube wall to determine the wall thickness. The transducer collects measurements as it continuously rotates and advances inside the tube. The thickness measurements collected, as the tube is scanned, are used to generate a high-resolution color plot. The length of the tube scanned can be adjusted, and a color scale indicates the range of wall thickness. The head has a permanent magnet attachment that reduces operator fatigue and increases positional accuracy for damage locations.

The system is capable of high speed scanning and a high rate of data return with high resolution. The scanning head has a high-performance Servo motor that moves the scanning head in and out and around the internal circumference of the tube, providing an image of the external corrosion.


The software allows the technician to continually view the ‘A’, ‘B’ and ‘C’ scans during the acquisition process. An integrated report compiler produces a tube sheet map which shows the minimum thickness of each tube scanned, as well as a clock position of the minimum thickness map. The software reporting feature allows the user to export a bitmap file of screen capture, as well a CVS file that can be converted into an Excel format, which can be included as part of a report. 

The system has a built-in calibration feature, in which the calibration standard thicknesses are permanently entered in the software, making the calibration process much easier and more accurate.

For additional information please contact us.