Instrument inspection

The same instrument inspects both steel and non-ferromagnetic tubing... 

All measurement and control instrumentation inspected, calibrated, and installed... 

When Hazard Studies are performed on new plants and modifications, certain inspection and test frequencies are defined. There should be a review process for changes. If equipment and instrumentation inspections reveal a pattern of failing to meet expectations, the testing or inspection should be increased and alternate equipment must be considered. 

FIG. 21-51b An X-ray system for detecting foreign matter in pack es. Courtesy ofEG G Instruments, Inspection System Division, Oak Ridge, TN 37830.)... 

The percentage of past-due equipment and instrumentation inspection and testing and... 

Depending on the requirements and costs, one method may be chosen over another provided it registers sufficient reliability. For example, whereas visual inspection is unreliable for small defects compared to an instrument inspection, in some aerospace in-service applications, it can be more cost-effective or practical to use visual inspection on a frequent basis than to conduct a more sensitive and costly instrument inspection less frequently to achieve the same service reliability of a component. It is common to specify that inspections require a signal-to-noise ratio (SNR) of >2.5 for the system sensitivity to the detection criteria of designated features in a calibration standard. Under a normal curve distribution, this would provide better than 98.7% detectability. 

Elements of a mechanical integrity program include identifying and categorizing equipment and instrumentation, inspections and tests and their frequency maintenance procedures traiifing of maintenance personnel criteria for acceptable test results documentation of test and inspection results and documentation of manufacturer recommendations for equipment and instrumentation. 

The suggested method is appropriately implemented at the practice. The cost and working hours of unit measurement of it is less than of any alternative method of destructive test and with respect to the authenticity inspection of Stress-Deformation the given method is inferior only to destructive testing. The method was successfully implemented while evaluation of service life of main pipe-lines sections and pressure vessels as well. Data of method and instrument are used as official data equally with ultrasonic, radiation, magnetic particles methods, adding them by the previously non available information about " fatigue " metalwork structure. 

Recently ultrasonic spectroscopy has become a more common NDE technique and specialized instruments are commercially available now for inspection of aerospace structures, ball bearings, and even concrete [2],[3]. 

The spectram acquired in this way can he used for characterization of the inspected object or detection of flaws in it. Since the spectram gathered by the modem instrument can consist... 

The performance of the classifier has been verified using a number of practical applications, such as civil engineering [3], inspection of aerospace composite structures, ball bearings and aircraft multi-layer structures. Here we present shortly some results, focusing on detection of disbonds in adhesively joint multi-layer aerospace structures using Fokker Bond Tester resonance instrument, details can be found in [1]. 

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. 

During the inspection of an unknown object its surface is scanned by the probe and ultrasonic spectra are acquired for many discrete points. Disbond detection is performed by the operator looking at some simple features of the acquired spectra, such as center frequency and amplitude of the highest peak in a pre-selected frequency range. This means that the operator has to perform spectrum classification based on primitive features extracted by the instrument. 

The war itself also drove the development of improved and miniaturised electronic components for creating oscillators and amplifiers and, ultimately, semiconductors, which made practical the electronic systems needed in portable eddy current test instruments. The refinement of those systems continues to the present day and advances continue to be triggered by performance improvements of components and systems. In the same way that today s pocket calculator outperforms the large, hot room full of intercormected thermionic valves that I first saw in the 50 s, so it is with eddy current instrumentation. Today s handheld eddy current inspection instrument is a powerful tool which has the capability needed in a crack detector, corrosion detector, metal sorter, conductivity meter, coating thickness meter and so on. 

Advances in Instrumentation for Remote Field Eddy Current Inspection. 

A visual method is considered by the most of regulations in force as a base for rope inspection. Instrumental methods using rope flaw detectors are considered as additional ones. But the visual methods have the number of shortcomings ... 

The research [5] showed the inspection records fulfilled by different instruments are very close each other. Nevertheless some of the instruments are able to put an information out to a computer, main inspection records usually are performed as chart diagrams of the LMA and LF channels. 

This is a double-channel flaw detector having their own microcomputer with 1 Mbyte memory to store data of the LMA and the LF channels for 800...2000 m of a rope under inspection. The instrument can be used in two modes as a tester for operative inspection or as a device for the inspection data storage. 

The INTROS Flaw Detector is certified by the Russian State Standard Service (GOSSTANDART) as well as approved by the Russian State Mining and Technology Safety Inspection (GOSGORTECHNADZOR). It is used to inspect mining hoist and crane ropes. Fig. 5 illustrates the INTROS use at the mining hoist of an Ural ore mine. The previous model of the instrument, MDK-11 was used to inspect ropes of the air rope ways in Caucasus and Kazakhstan in 1996. Fig. 6 shows the INTROS MDK-11 inspection of 45 mm skyline rope in Almaty, Kazakhstan. 

Many inspection problems cannot simply be solved by means of standard NDT equipment Also in the ultrasonic field many applications require a special adaptation of instruments and especially the probes to the requirements of the inspection problem. 

Our solution for this inspection problem is a special ultrasonic system consisting of a special probe and a modified pulse-echo ultrasonic instrument. 

The new instrument introduced for inspection of multi-layer structures from polymeric and composite metals and materials in air-space industry and this is acoustic flaw detector AD-64M. The principle of its operation based on impedance and free vibration methods with further spectral processing of the obtained signal. 

The "Plant Life Assessment Network" (PLAN), was started on the 1/12/1997, established around EU funded research projects working in the area of inspection, instrumentation, monitoring, structural mechanics and maintenance. 

Edcfy-cufrent NDT inspections using spatial data (sampled scans) ha >e many benefits. They separate the two conflicting aspects of an inspection scanning and signal interpretation. An instrument/display (client/server) based NDT inspection based on sampled scan data aides in the training and certification of inspectors. It can be used over the Internet or in-house Intranet networks to train or examine inspectors at multiple or remote sites. This saves travel time and resources as defects, instrumentation and teaching can all be consolidated Samples can be maintained and distributed from a central certification body providing more control andflexibility. 

The review should emphasize developing an understanding of the processing sequence, the equipment, the equipment plot, the operating conditions, instrument and sample locations, the control decisions, and the operators perspectives. Wmle the preparation effort may be less for those who have been responsible for the unit for a long period of time, the purpose of the test requires that the types and locations of the measurements be different from those typically recorded and typically used. The condition of these locations must be inspected. Operating specifications may be different. Therefore, refreshment is always necessaiy... 

---