TPT March 2007

I nspection, M easuring, T esting & M arking

Ultrasonic full-body inspection system for ERW and seamless tube

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A total of 60 probes are utilised, covering longitudinal, transverse defects and wall thickness measurement

NDT Systems & Services AG, Germany, have designed an inspection system for the fully automated ultrasonic inspection of ERW and seamless tubes with diameters from 140-400mm and wall thicknesses from 3-25mm. For full-body

inspection, the tube is spirally guided through several inspection basins where probes are installed at different angles of incidence.

Coupling is achieved by utilising the partial immersion technique

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fi Inspection basins for the detection of longitudinal defects

(PIT). In order to obtain a high inspection speed, a total of 60 probes are utilised, covering longitudinal, transverse defects and wall thickness measurement. Inspection is carried out on a helical track width of 150mm. To ensure 100 per cent inspection coverage, a 10 per cent overlap of the neighbouring scanning tracks has been implemented for the effective tube feed of >135mm/revolution.

Depending on the tube diameter, inspection velocities of a maximum of 0.35m/s are achieved. Angularly adjustable pairs of the helical rolls driven by motors are used for the helical transport of the tubes. The angle setting depends on the tube diameter and ranges from 7-30°. The inspection basins, two for each inspection mechanics, are lifted towards the tube and lowered by a sensor- controlled pneumatic system, ensuring that the inspection basins are lifted only when the leading edge of the tube has reached a defined position. The vertical and horizontal transverse movement of the helically transported tube is transmitted to the inspection basins by means of guiding rolls. Due to the small immersion depth and the helical movement, coupling water is prevented from entering the tube. When the trailing edge has reached the corresponding probe, the ultrasonic electronics are automatically switched off in order to avoid false indications. The tubes pass the inspection line at a distance of 1.5-2m from each other. True- to-location in axial direction, spraying guns mark the location of detected flaws on the tube. For each tube, the inspection results are stored in the form of a strip chart recording of the ultrasonic signal (A-scan). In addition, they are provided as a C-scan with coloured marking of the type and location of the detected flaws, together with a summarizing tube protocol. Depending on the inspection results, the kick-out unit sorts the inspected tubes according to accepted or rejected.

Scanners for wall thickness measurement Swiss manufacturers of in-line measuring, monitoring and control systems, Zumbach Electronic has launched a new range of ultrasonic wall thickness scanners, branded UMAC ® Z50 and Z100.

The transducers of the scanners can be synchronously adjusted to the best possible measuring position within seconds, and can be motorised on request. The scanners cover an outside diameter range from 5mm to 100mm (0.2" to 4") depending on the model, and provide a simple solution for fully non-contact, in-line wall thickness measurement of cable jackets, tube and hose. The scanners are compact, allowing installation into the cooling trough directly after the extruder. They are manufactured using non-corrosive materials for maintenance-free long-life operation

› UMAC Z50 scanner with 6 measuring points

underwater. Available for four and six point measurement, the scanners feature a quickly removable segment to enable easy product change within a few seconds. In combination with the Wallmaster data acquisition, processing and display system from Zumbach, a full process control can be achieved.

Zumbach Electronic AG – Switzerland Fax : +41 32 356 0430

NDT Systems & Services AG – Germany Email : Alexander.schmid@ndt-ag.de

Email : sales@zumbach.ch Website : www.zumbach.com

Fax : +49 7244 7415 97 Website : www.ndt-ag.de

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