Real time

Figure 5.37 depicts the basic set up of a wireline logging operation. A sonde is lowered downhole after the drill string has been removed. The sonde is connected via an insulated and reinforced electrical cable to a winch unit at the surface. At a speed of about 600m per hour the cable Is spooled upward and the sonde continuously records formation properties like natural gamma ray radiation, formation resistivity or formation density. The measured data is sent through the cable and is recorded and processed in a sophisticated logging unita the surface. Offshore, this unit will be located in a cabin, while on land it is truck mounted. In either situation data can be transmitted in real time via satellite to company headquarters if required. 

Data transmission rate per foot is a function of both pulse frequency and rate of penetration. Sensors acquire and transmit data samples at fixed time intervals and therefore the sampling per foot is a function of rate of penetration. Current tools allow a real time sampling and transmission rate similar to wireline tools as long as the penetration rate does not exceed about 100 ft/h. If drilling progresses faster or if there are significant variations in penetration rate, resampling by depth as opposed to time intervals may be required. 

Stegemann, D, Reimche, W. Schmidtbauer, J. Investigations of Light Metal Casting Processes by Real Time Microfocus Radioscopy. The European Journal of Nondestructive Testing, Vol. l,No. 3, S. 107117, Jan. 1992... 

The particularity of acoustic emission tests is that, during pressurization and in real time, they reveal any defects which are evolving and which may lead to premature cracking of the vessel during the test or in serviee. 

The aim is to develop a real-time surveillance method to ensure the safety of tests such as resistance tests and re-testing of pressure vessels, based on measurement carried out using acoustic emission technology. 

This monitoring method should make it possible to decide wether to continue with the pressurization of the vessel or to stop it, based on real-time and reliable detection and location of any potentially hazardous defect which is evolving. 

Digital Signal Processor board fPSP) it is hosted into the PC and processes in real time the binary sequences stored into the acquisition board FIFO memories. The board processes arrival times and extracts the correlated AT generated by AE events. The PC picks up the data stored into the DSP memories and calculates the position of the AE sources. 

The AEBBL SW ains on the PC. The software uses a menu structure, easy to use by a non expert operator. AEBIL has been designed to operate in DOS environjnent in order to enhance its real-time operation capabilities. The user-interface has been developed so as to permit a window-driven operation. 

DRAI (R.), BENTALEB (N.), ABDAT (F.), SELLIDJ (F), Application of real time ultrasonic imaging method for control of materials, Atmales de Chimie - Sciences des materiaux. Vol.22, 143, 1997. 

Technology has converged and seems likely to continue to do so, particularly with the parallel developments in the personal computer. The P.C. today has the power needed to analyse and interpret the often confusing responses obtained in eddy current tests, in real time as the tests are being made. The responses we get from a testpiece come, as we all know, equally from features we are not interested in as they do from significant features. 

CPU. A standard Motorola CPU was selected, which works under a powerful real-time, multi-task operating system (VxWorks), and has embedded Ethernet interface. This CPU also features 4 IP slots to which can be plugged ... 

Additional assistance is provided by secondary modification options that allow among others for a depiction of the original signal, the reconstruction of the depiction of the impedance plane of the eddy-current signals or for modifications of phase, amplification or zero point virtually in real time. That way, once C-scan images have been recorded, they can now be evaluated as needed without having to repeat the test. 

It would be tlierefore thus easy to obtain in real time, on computer, tlie image of a long standard defect that is to even to produce the impedance variation observed. It would be thus possible to realize the control by absolute measures and to avoid the recourse to standard defects. 

The inspection class SA is based on the requirements of real-time serial inspection that are covered by standard minifocus X-ray tubes. 

Suitability of Gadolinium Based Systems for X-Ray Real Time Radiography. 

Real Time Radiography (RTR) is an advanced method of radiography in which the image is formed while the job is exposed to ionising radiation. RTR is often applied to objects on assembly lines for rapid inspection. Accept-or-reject decisions may be made immediately without the delay or expense of film development. The main advantages of RTR are thus, reduction in inspection cost and processing time. 

Of all NTD methods for quality control of materials, products, welded and soldered joints the most informative and perspective are radioscopic ones that enable to obtain a visual image of an inner structure of a tested objects in real time under any projection. 

A Real Time X-Ray Inspection System is introduced to replace Film X-Ray. The main objective is to reduce the consumption of film and to reduce the environmental pollution due to lead intensifying screens and chemicals. Other benefits are the reduction of space to storage X-ray data and the shorter inspection time, which gives a faster feed back to production. 

The efficiency of gas turbines is limited by the maximum allowable turbine inlet temperature (TIT). The TIT may be increased by cooling of the blades and vanes of the high pressure turbine. Cooling channels can be casted into the components or may be drilled afterwards. Non-conventional processes like EDM, ECD or Laser are used for drilling. Radiographic examination of the drilled components is part of the inspection procedure. Traditional X-Ray film technique has been used. The consumable costs, the waste disposal and the limited capacity of the two film units lead to the decision to investigate the alternative of Real-Time X-Ray. 

In this paper the technical specifications of a Real Time X-Ray system are given. The procedure for inspection is explained briefly. The resolution of film and of Real Time X-Ray inspection are compared. The basic equipment needed to inspect Real Time X-Ray data is defined. 

The lead time for making a image by film X-Ray is 10 to 15 minutes. Where about 2 minute are needed in inspection by Real-Time X-Ray. Another advantage of Real-Time X-Ray is the feature that the effect of manipulating the part or changing the setting of the X-Ray tube can be observed directly. This is often used in investigating quality problems. 

Real Time X-Ray images are stored on CD ROM/XA. Compared to film the volume for a storage is reduced by a factor 50. Retrieving is easy since information of the location is given in the directory of the diskette. Normally the directory name is the shop order and the file name is the serial number of the part. The directory and file names can be customised. 

The resolution of images of the Real Time X-Ray system depend on the material thickness and on the settings of the system. While setting up the Real Time X-Ray inspection of parts the resolution is compared with the resolution aehieved in film bases X-Ray as used over the last years. It is demonstrated that the sensitivity of Real Time X-Ray meets the specification of DIN 54109 Bildgtitteklasse II. 

An advantage of Real Time X-Ray is that since only one section of the part is inspected at the time the X-Ray parameter settings can be optimised per section. At the same time each section is irradiated almost perpendicular which gives less distortion in the image of the top and the bottom section of blades. 

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