Mounting

Hunter et al. have mounted their sensors by gluing the SiC sensor chip onto a thin membrane realized by spin-on glass, with a heater and temperature detector underneath. This mounting technique enabled operation of the sensor at 600°C with a heater power of close to IW [4]. 

Micromachining in SiC is developed by several groups, for a review see [129]. Solzbacher et al. have constructed a microhotplate based on a SiC-membrane and a HfB thin-film heater, where the active part of the membrane is separated from the surroundings by six SiC microbridges. The heater is designed for operation temperatures up to 700°C and can be operated at 400°C with a power of 35mW [130, 131]. Boston Microsystems also offers a monolithic microhotplate in SiC [132]. 

AT-Ray Sources.—Rosenbaum et al have described some preliminary results using synchrotron radiation as a source particularly for AT-ray diffraction of fibres. They have used the 7.5 GeV electron synchrotron Deutsches Hektro-nen-Ssmchroten in Hamburg. Calculations show that the spectral luminance 

Blundell and L. N. Johnson, Bienniai Reviews of Chemistry, 1972, in the press. 

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Liquid injection incinerators. This t3q)e of incinerator has a cylindrical refractory-lined combustion chamber mounted verti-... 

X-ray spectrometer An apparatus used in the X-ray study of crystals in which a fine beam of monochromatic X-rays impinges at a measured angle on the face of a crystal mounted in its path, and in which the intensity of the X-rays diffracted in various directions by the crystal is measured with an ionization chamber mounted on an arm of the spectrometer table, or is recorded photographically. 

For onshore operations various types of landrigs are available, ranging from truck mounted light rigs to heavy landrigs weighing several hundred tons. 

Swamp Barges operate in very shallow water (less than 20 ft). They can be towed onto location and are then ballasted so that they sit on bottom . The drilling unit is mounted onto the barge. This type of unit is popular in the swamp areas of Nigeria. 

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. 

For direct measurement from core samples, the samples are mounted in a holder and gas is flowed through the core. The pressure drop across the core and the flowrate are measured. Providing the gas viscosity (ji) and sample dimensions are known the permeability can be calculated using the Darcy equation shown below. 

The progressive cavity pump consists of a rotating cork-screw like sub-surface assembly which is driven by a surface mounted motor. Beam pump rods are used to connect the two. The flowrate achieved is mainly a function of the rotational speed of the subsurface assembly. There Is in principle very little that can go wrong with progressive cavity pumps. Progressive cavity pumps excel in low productivity shallow wells with viscous crude oils and can also handle significant quantities of produced solids. 

The manifold is typically a tubular steel structure (similar to a template) which is host to a series of remotely operated valves and chokes. It is common for subsea tree control systems to be mounted on the manifold and not on the individual trees. A complex manifold will generally have its own set of dedicated subsea control modules (for controlling manifold valves and monitoring flowline sensors). 

Modern subsea trees, manifolds, (EH), etc., are commonly controlled via a complex Electro-Hydraulic System. Electricity is used to power the control system and to allow for communication or command signalling between surface and subsea. Signals sent back to surface will include, for example, subsea valve status and pressure/ temperature sensor outputs. Hydraulics are used to operate valves on the subsea facilities (e.g. subsea tree and manifold valves). The majority of the subsea valves are operated by hydraulically powered actuator units mounted on the valve bodies. 

Thus they have been replaced with elements with a martensite structure mixture fully transformed by the zero processing and mounted in openings with insens of austenite steel (Fig.3). Thus prepared elements for caUbration. will be stable with time and will not cause any indication changes during exploitation. 

The first 3 items of the above list (waveguides, transducers and preamplifiers) are located at or near to the component(s) to be monitored. The other items must be installed in the control room area, mounted into a single instrumentation rack (fig. 4). 

Cracks detection in welds, mounting hardwares, rivets, on blades and vanes, turbine disks, rotors blades, etc. 

Inspection of load - carrying structures and mounting hardwares, the defects detection under side platings and dielectric shells in their attaching points to the load - carrying structures. 

The air is streaming through the supply pipes directly into the blade which is mounted on a turntable. The blade is measured in different positions, so that all important surface areas can be examined. The time for a complete blade examination is approximatly 5 minutes. The blades or vanes are mounted manuell, otherwise the process is running fully automatically. 

For the examination of the applied metallic or ceramic layer, the test object is heated up from the outside The heat applying takes place impulse-like (4ms) by xenon-flash lamps, which are mounted on a rack The surface temperature arises to approx 150 °C Due to the high temperature gradient the warmth diffuses quickly into the material An incorrect layer, e g. due to a delamiation (layer removal) obstructs the heat transfer, so that a higher temperature can be detected with an infrared camera. A complete test of a blade lasts approximatly 5 minutes. This is also done automatically by the system. In illustration 9, a typical delamination is to be recognized. 

Inherent unsharpness U of the imaging system An edge of highly absorbent material that is mounted in the middle of the image converter, is used to define the course and width of the "blurred" edge. The unsharpness is defined between 10% and 90% of the amplitude of the output signal. 

Contrast Ratio Cq The contrast ratio is established on the basis of the ratio of the amplitude of the unattenuated radiation to the amplitude after attenuation through a test piece. This test piece is a lead disk which is mounted in the middle of the image converter it masks approximately 10% of the surface of the image converter. 

For testing under field conditions a new mobile version of introscope has been developed, mounted on a lorry with high cross-country capability and self-contained power supply. 

The detector setup consists of four 256 x 256 pixel amorphous silicon technology sensor flat panels with 0.75 x 0.75 mm pixel size, having an active area of 192 x 192 mm [5j. These sensors are radiation sensitive up to 25 MeV and therefor well suited for detecting the LINAC radiation. The four devices are mounted onto a steel Irame each having the distance of one active area size from the other. With two vertical and two horizontal movements of the frame it is possible to scan a total area of about 0.8 x 0.8 m with 1024 x 1024 pixel during four independent measurements. 

The specific advanced properties of the ceramic insulator eliminate the need for oil or resin insulation. The metal vacuum envelope of the tube provides higher beam stability, more robust design, and even X-ray shielding up to certain levels. Furthermore, even difScult mechanical problems (e.g. mounting, coohng, or beam emission) can be solved by an appropriate customised tube design. 

The changes described above also allowed much easier access to the high voltage cable for routine (6-month) owner directed, service operations, and provided better upper and lower x-ray cabinet and control cabinet ventilation. With the exception of the x-ray tubes, all the individual manufactured components, on all four systems are identical. There are very subtle differences in the warm-up/start-up sequence on the x-ray controllers on the newer systems due to model/year and x-ray tube differences. The last three systems were supplied with environmental type key-boards for the image processors and base-mounted , rather than conduit-mounted exterior warning indicators. The first system was subsequently upgraded to include the better keyboard and the external warning appliances/features. 

Fig. 2 shows the CFRP-sandwich specimen and the transducer mounted on the scanner. Fig. 23 presents a C-scan of the specimen as first interesting result. Only the defects visible from the outside are indicated. The distance between transducer and specimen was smaller than the focal length, so that the angle of incidence at the edge of the sound beam converts the longitudinal waves to Rayleigh-waves in the specimen. These waves provide a very sharp image of the surface. This method opens the possibility for a non-contact acoustic microscope. 

Another feature is a repositioning program (Repos.exe) which is used for the purpose of correcting positioning data collected when scanning on a pipe elbow or when scanning is performed with the microphone collar mounted on the elbow itself... 

Figure 2 AIR-1 robot mounted on incbned inspection nozzle...

The method is based on the international standard ISO 4053/IV. A small amount of the radioactive tracer is injected instantaneously into the flare gas flow through e.g. a valve, representing the only physical interference with the process. Radiation detectors are mounted outside the pipe and the variation of tracer concentration with time is recorded as the tracer moves with the gas stream and passes by the detectors. A control, supply and data registration unit including PC is used for on site data treatment... 

For this kind of case, a modification of the dilution method is being developed. Instead of using an external fixed-geometry measurement chamber, a suitable part of the process, e.g. a stretch of pipe, is used. A radiation detector is mounted on the outside of the pipe, and a tracer emitting sufficiently hard gamma radiation is used. As sufficient mixing can be achieved by injecting upstream the separator the radiation level found will be strictly proportional to the concentration and thus inversely proportional to the true flow rate. 

The size of the leakage was determined as follows. Radiation detectors were mounted on the inlet of the first side, and the outlet of the second side of the heat exchanger and at additional locations for control. A short pulse of Kr-85 tracer (<0.1 sec) was injected into the feed stream, which gave rise to detector responses shown in figure 3. 

The uppermost curve shows the response from the detector mounted on the heat exchanger... 

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