Inspections ultrasonic

Main steamline section and weld of the same Unit 4 f600 MW3 as above the weld connects 2 steamline sections of different materials (stainless steel and low-alloy steel) through a transition material section, ahead of the Y-piece where branching of the turbine inlet lines takes place (255 mm internal diameter, 44.5 mm thickness). Ultrasonic inspection pointed out potential integrity problems in the weld. The requirement was again that AE could support safe operation of the weld until the next incoming planned maintenance shutdown. 

This header has undergone repair after through-thickness cracking of an assembly weld after 108.000 hours of service, it is presently in operation and periodically submitted to ultrasonic inspection during planned maintenance shutdown. Continuous on-line AE monitoring of the integrity of critical welds is expected to contribute supporting continued and safe operation of the header until its replacement, platmed to take place in 1999. 

No firm conclusion should be drawn from the above data, through the observed pattern deserves attention. The AE activity observed on the SH header can originate from the weld, but could be due to other causes, namely to the settlement of the hanger. Ultrasonic inspection of the weld at regular intervals checks whether any sizeable change in NDT response from the weld has taken place. 

Fokker Bond Tester. An ultrasonic inspection technique commonly used for aircraft structures is based on ultrasonic spectroscopy [2]. Commercially available instruments (bond testers) used for this test operate on the principle of mechanical resonance in a multi-layer structure. A piezoelectric probe shown in Figure 3b, excited by a variable frequency sine signal is placed on the surface of the inspected structure. A frequency spectrum in the range of some tens of kHz to several MHz is acquired by the instrument, see Figure 3a. 

Vagnhammar B., L.Ericsson, T. Stepinski and B. Grelsson, Improved defect detection in ultrasonic inspection of bonded structures. Report UPTEC 97 105R, Uppsala University, June, 1997... 

Chapman, R.K., "A system model for the ultrasonic inspection of smooth planar cracks", J. Nondestruct. Eval., 1990,9, 197-211. 

Lakestani, F., Validation of mathematical models of the ultrasonic inspection of steel components, PISC III report 6, IRC Inst. Adv. Mater., Petten, 1992. 

The main purpose of AUGUR4.2 expert ISI is the application to zones where some flaws (indications) had been revealed by scheduled manual ultrasonic inspections. Information provided by AUGUR 4.2 is used for decision-making further surveillance of these zones or corrective measures. The procedure of AUGUR 4.2 examination is included into the approved general scheme of ISI [1]... 

Representative set of weldments was examined site welds (with pearlitic type weld metal) and two types of site weld repair zones with different welding technologies using Cr-Ni filler metals and Ni-based alloy. Results of AUGUR 4.2 inspection were compared with manual ultrasonic inspection ones in terms of defect detection, characterization, positioning and sizing in order to estimate correlation between these data. 

Some of the problems often encountered during ultrasonic inspection of plane specimens are also found on cylindrical specimens. For example, problems associated with the directional characteristic of the ultrasonic transducer. Furthermore, the discontinuity influences the shape and propagation direction of a reflected pulse, causing wave mode transformation. In addition, the specimen influences the shape and amplitude of the reflected pulse by sound absorption. 

The procedure generation, data acquisition and data visualisation modules of the CamuS system described in this paper provide assistance with manual ultrasonic inspection by ... 

With reference to obtained results the high-teeh manual ultrasonic inspection performed by ISONIC system becames competitable with radiography, providing highest sensitivity, low inspection cost, obvious and objective documentation. 

Figure 6 AIR-1 articulated robot arm with six degrees of freedom Robot performs ultrasonic inspection of a large nozzle weld on a BWR main circulation pipe.

Ultrasonic Inspection of a CFRP- Sandwich Specimen with an Air-coupled Transducer... 

We decided already in 1994 to develop PC boards for ultrasonic inspections [1,2]. 

The HILL-SCAN 30XX boards enable ultrasonic inspections from 50 kHz (concrete inspections) to 35 MHz (inspection of thin layers) with a signal to noise ratio up to 60 dB. The gain setting range of the receiver is 106 dB. High- and low pass filters in the receiver can be combined to band-passes, so that optimal A-scans are displayed. 

Hillger, W. Friederiehs, B. Ultrasonic Inspection of the Helicopter EFI 101 Tail Unit, Brite Euram Project No. BE-5781, Document No. DAMTOS-WP-503-1.1/DLR, 1995... 

With the development and introduction of a new complete 3D ultrasonic inspection system FORCE Institute enlarges the inspection possibilities and increases the overall quality of UT inspection of complex geometry components. 

Gundtoft, H. E., Agerup, C. C. and Nielsen, T. A New Ultrasonic Inspection System for Non-destructive Examination of Precision Tubes", NDT International August 1977,... 

Application of Surface SH Wave s Detection Standard for the Ultrasonic Inspection of Weld Defects in Steel Structures, 3rd Revision, Architectural Institute of Japan, P27, (1996)... 

Studying modem approaches for such schemes, one can see that knowledge of operational conditions and potential degradation mechanisms play a prominent role. Surprisingly, the role of NDT is often limited to tlie use of conventional methods such as ultrasonic wall thickness measurements, ultrasonic inspection, radiography, and last but not least visual inspection. 

Automated Ultrasonic Inspection of Large Rotorblades for Windmills. 

Many of the inspection problems posed by composites can be dealt with effectively by ultrasonic. Delaminations, bonding defects, impact damage, cavities and porosities are among the typical defects which can de detected by ultrasonic inspection. 

In co-operation with LM Glasfiber, a complete section of a rotor blade was produced with a number of well defined defects in order to perform an initial sensitivity test by means of ultrasound, vibrations techniques and real-time radiography. Based on the results of this initial test it was found that automated ultrasonic inspection was the best suited teclmique. In co-... 

Automated ultrasonic inspection of bonded joints and laminates of rotor blades. 

Automated ultrasonic inspection of filament winded beams... 

The coin-tap test is a widely used teclinique on thin filament winded beams for detection of disbonded and delaminated areas. However, since the sensitivity of this teclinique depends not only on the operator but also on the thickness of the inspected component, the coin-tap testing technique is most sensitive to defects positioned near the surface of the laminate. Therefore, it was decided to constructed a new scaimer for automated ultrasonic inspection of filament winded beams. A complete test rig illustrated in figure 6 was constructed in order to reduce the scanning time. While the beam rotates the probe is moved from one end to the other of the beam. When the scarming is complete it is saved on diskette and can then be evaluated on a PC. The scanner is controlled by the P-scan system, which enables the results to be presented in three dimensions (Top, Side and End view). 

Lalumandier, S. and Cowling, T., Integrated Laser Profilometry/Ultrasonic Inspection System for Furnace Tubes ASNT Fall Conference, Pittsburg PA, 1997. 

Ultrasonics. The most widely used nondestmctive test method for explosion-welded composites is ultrasonic inspection. Pulse-echo procedures (ASTM A435) are appHcable for inspection of explosion-welded composites used in pressure appHcations. 

For pipelines in service in chemical plants, it is not usually convenient to place a radiation source inside the pipe and position it to irradiate each welded joint. The radioisotope source container maybe placed on the outer surface of the pipe. The radiation beams then pass through two pipe wall thicknesses to expose films placed diametrically opposite the radiation source, also on the outside of the pipe wall. Other methods, such as magnetic particle inspection of welds in steel pipe, or ultrasonic inspection of welds in pipes of all materials, supplement x-rays in many critical appHcations. The ultrasonic tests can often detect the thin, laminar discontinuities parallel to the pipe surface or the incomplete fusion discontinuities along the weld... 

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