Inspection tasks

The whole knowledge acquisition process is also a burden for the inspection company, especially a smaller one, as it prevents the expert from taking part in routine inspection tasks. 

A major advantage of radioscopy is the flexible inspection perspective that allows an optimum adjustment of beam direction and geometrical magnification to the inspection task at hand it also permits in-motion testing. 

The three-part draft of the radioscopy standard pr EN 13068 is ready for the necessary european inquiries. This standard covers the requirements placed on the imaging system, the checking procedures as to the performance of the entire system and also the specifications of user guidelines for certain inspection tasks. The standard remains open to the definition of new inspection classes for future application cases. 

For this purpose a specially bended probe holder was designed for this inspection task on the actual engine, as it is demonstrated in figure 6 ... 

However, this probe design is dedicated to a special turbine blade type and a special inspection task on this blade. But similar probe types and probe holders can be provided also for other engine types and for other inspection tasks like wall thickness measurement and crack detection in other zones of a blade. 

The 3D-inspection system can be applied to many complex inspection tasks where ordinary XY scanners can not perform the job, e.g. nozzle welding inspections and nozzle inner radius inspection in nuclear and petrochemical environments. 

Some companies make piping service evaluations. These evaluations are used to categorize piping systems and determine the initial piping inspection intervals and degree of inspections for critical piping systems. A team determines which inspection tasks are needed to lower the likelihood of failure occurrence. A matrix is established to determine the type of inspection and the interval between inspections. This service evaluation is beyond the scope of this chapter. 

Additional Large Scale Process Qualification Studies Product Transfer Document Issued Product Acceptance by Manufacturing Validation Protocols Written Pre-approval Inspection Task Force Initiated Manufacturing Site Preparation Pre-approval Inspection by FDA... 

Use preventive maintenance if it is apparent that predictive maintenance tools do not adequately apply. Inspection tasks must be developed that reveal the defects not adequately covered by preventive maintenance. 

After you have decided the combination of inspection methods, determine the frequency at which the particular inspection tasks must be applied. 

Clearly, knowledge-based functioning in decision depends upon accurate knowledge of costs, probabilities, and the process of optimization. Misperception of costs and values and misperception of prior defect probabihties can lead to incorrect decisions on criterion placement. Decision support for cost and value perceptions is simple in principle, although it is almost never formalized in an inspection task. Support for estimation of the true defective rate for each type of defect is much more difficult because it is based upon the output of the inspector, or of another inspector who is likely to be equally error prone. It is possible to provide such data to the inspector using another inspector who is allowed more time and/or resources for the decision. When these data are provided as feedforward of likely defect types and probabilities (Sheehan and Drury 1971) or as performance feedback (Drury and Addison 1973), dramatic reductions in error are found. 

The inspection task combines two goals detection of expected medfunctions and detection of unexpected malfunctions. Neither detection is particularly easy or particularly rapid, so inspection can be a difficult and time-consuming task. In some ways inspection can be classified as an ill-structured task (Wenner 1999) because there is no simple step-by-step procedure that will ensure success and usually no knowledge of task success available during the task. Finding (n) malfunctions in a structure still leaves an unknown number (hopefully zero) potentirilly undetected. 

The inspection task itself is classified in aviation as either visual inspection or nondestructive inspection. Regulatory bodies have issued formal descriptions of both of these tasks (e.g., Bobo 1989, for the FAA), and both have somewhat different characteristics in aviation... 

Nondestructive inspection (NDI) includes a set of techniques to enhance the ability to detect small and/or hidden malfunctions. One set of NDI techniques is those that enhance what is essentially still a visual inspection task, such as X ray, fluorescent particle, magnetic particle, or D Sight. They show cracks that are very small (fluorescent particle) or hidden within other structures (X ray). Apart from the steps necessary to ensure a good image, they have many of the human interface characteristics of visual inspection. The other set of NDI techniques is focused on specific malfunctions in specific locations, such as eddy current and ultrasound. For this reason, they are useful only for detection of malfunctions already predicted to exist. In practice, such NDI techniques are much more procedur-alized than visual inspection or NDI techiriques, which contain a human visual inspection component. 

Such a task description invites task analysis, which would lead naturally to human reliability analysis (HRA). Indeed, perhaps the earliest work in this field applied HRA techniques to construct fault trees for aircraft structural inspection (Lock and Strutt 1985). The HRA tradition lists task steps, such as expanded versions of the generic functions above, lists possible errors for each step, then compiles performance shaping factors for each error. Such an approach was tried early in the FAA s human factors initiative (Drury et al. 1990) but was ultimately seen as difficult to use because of the sheer number of possible errors and PSFs. It is occasionally revised, such as in the current FRANCIE project (Haney 1999), using a much expanded framework that incorporates inspection as one of a number of possible maintenance tasks. Other attempts have been made to apply some of the richer human error models (e.g.. Reason 1990 Hollnagel 1997 Rouse 1985) to inspection activities (La-toreUa and Drury 1992 Prabhu and Drury 1992 Latorella and Prabhu 2000) to inspection tasks. These have given a broader understanding of the possible errors but have not helped better define the PoD curve needed to ensure continuing airworthiness of the civil air fleet. 

Wang, M-J., Drury, C. G., and Sharit, J. (1986), An Application of Fuzzy Set Theory for Evaluation of Human Performance on an Inspection Task, in Applications of Fuzzy Set Theory in Human Factors, W. Karwowski and A. Mital, Eds., Elsevier, Amsterdam, pp. 257-268. 

Model (7.1) is e.g. used for inspection tasks (as deformation measurements) or target tracking to support the navigation of moving vessels. In the case of deformation measurement tasks the actual position vector Xa, measured by the robot system, is compared with the desired position vector ... 

Typical inspection tasks of important work-piece characteristics for the functionality of a product are ... 

Once out of the vertical attitude the chain can be extended as a stiff cantilever to carry out various inspection tasks within the reactor internals. In addition to link extension and serving angle, additional movements are provided for mast raise/lower and rotation, as well as two articulators plus rotation at the end of the link chain. 

Quality assurance zone The system directs workers to pick and put the received materials into the quality assurance zone. As soon as the materials are put into the quality assurance zone, the system generates inspection tasks. Quality inspectors can inquire about the unfinished inspection tasks using personal computers. Quality inspectors inspect the materials and input inspection results through system clients installed on personal computers. Then the system auto-prints inspection result labels, and inspectors stick those labels onto associated packages of materials. 

I understand the brake service or inspection task to be accomplished and can perform that task and... 

C) Experience performing brake maintenance or inspection similar to the assigned brake service or inspection task at a commercial garage, fleet leasing company, or similar facility ... 

Consider vision systems for repetitive complex inspection tasks. 

Inspection tasks. It is often necessary to inspect inner cavities of machines or pipe systems without disassembly or destruction. Endoscopes are available for this task, but these (albeit flexible devices) are insufficient if the object under inspection has a very complex geometry or exact positioning is required. Here, SM actuators promise more degrees of freedom and more controllability, and are formed into smaller devices. 

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