Lining applications Linings

For-della connected capacitor units In (his case, it will establish a line-to-line fault with a heavy fault current. Protection by HRC fuses would be more appropriate than for a grounded star or using an MCCB. For series-parallel connected units I his is applicable in HT capacitor banks comprising a number of small units arranged in series and parallel combinations. The fault current in such cases for an isolated neutral can be expressed by... 

A period of time over which the input line voltage completely disappears (the specification is typically 8mS for 60Hz ac off-line applications). 

In ae off-line applications the common-mode choke is typically used and its design procedure can be found in Appendix E. The Alters resemble pi Alters, but are actually bi-directional L-C Alters. The important function is to Alter the noise generated by the switcher before it exits via the input power lines. 

A PWM switching power supply that is designed with no extraordinary loss-control methods will exliibit efficiencies as seen in Table 3-3. For switching power supplies that have no problem in getting rid of the heat, such as some off-line applications, the aforementioned efficiencies may be satisfactory. For portable applications and equipment that must be small in size much better efficiencies must be sought. To improve the overall efficiency of a power supply, several techniques can be used. 

A number of gases may decompose (self-react) and propagate flames in the absence of any oxidant provided that they are above minimum conditions of pressure, temperature, and pipe diameter. Common examples are acetylene, ethylene oxide, and ethylene. Some, like acetylene, can decompose in a detonative manner, while ethylene cannot detonate in the absence of an oxidant, whatever the run-up length (CCPS 1993). Thus, detonation arresters must be used for acetylene, but deflagration arresters may be used for ethylene, even for in-line applications. 

The flame propagation direction affects the type of flame arrester selected. An end-of-line or in-line deflagration flame arrester used for the protection of an individual tank may be of a unidirectional design because the flame will only propagate from the atmosphere towards the tank interior. A bidirectional flame arrester design, however, is needed for an in-line application in a vapor recovery (vent manifold) system because the vapors must be able to flow from the tank interior into the manifold, or from the manifold into the tank interior. Consequently, flame may propagate in either direction. 

Type I Flame arresters acceptable for end-of-line applications. Where a Type I arrester is provided with cowls, weather hoods, or deflectors, etc., it shall be tested in each confignration. 

Type II Flame arresters acceptable for in-line applications. Type II arresters shall be specifically tested widi the inclnsion of all pipes, tees, bends, cowls, weather hoods, etc., which may be fitted between die arrester and the atmosphere. Owing to the prohibitive cost of testing deflagration flame arresters for each particular installation, the Type II (in-line) category is generally not enconntered. 

An approved flame arrester should not he misapplied, i.e., an end-of-line arrester should not he installed in an in-line application. 

The production of a rubber lining includes the preparation of the rubber compound followed by processing to form the lining sheet, substrate preparation, lining application, vulcanisation and inspection. All these stages require thorough quality control, especially compound manufacture and sheet preparation, as chemical resistance depends on satisfactory dispersion of the individual ingredients and undetected flaws in the sheet will cause problems in service. 

Three parallel collection lines were located 50 ft apart and perpendicular to the application line. This pattern allowed three replicate measurements to be made at... 

XRF nowadays provides accurate concentration data at major and low trace levels for nearly all the elements in a wide variety of materials. Hardware and software advances enable on-line application of the fundamental approach in either classical or influence coefficient algorithms for the correction of absorption and enhancement effects. Vendors software packages, such as QuantAS (ARL), SSQ (Siemens), X40, IQ+ and SuperQ (Philips), are precalibrated analytical programs, allowing semiquantitative to quantitative analysis for elements in any type of (unknown) material measured on a specific X-ray spectrometer without standards or specific calibrations. The basis is the fundamental parameter method for calculation of correction coefficients for matrix elements (inter-element influences) from fundamental physical values such as absorption and secondary fluorescence. UniQuant (ODS) calibrates instrumental sensitivity factors (k values) for 79 elements with a set of standards of the pure element. In this approach to inter-element effects, it is not necessary to determine a calibration curve for each element in a matrix. Calibration of k values with pure standards may still lead to systematic errors for unknown polymer samples. UniQuant provides semiquantitative XRF analysis [242]. 

Clearly, the potential applications for vibrational spectroscopy techniques in the pharmaceutical sciences are broad, particularly with the advent of Fourier transform instrumentation at competitive prices. Numerous sampling accessories are currently available for IR and Raman analysis of virtually any type of sample. In addition, new sampling devices are rapidly being developed for at-line and on-line applications. In conjunction with the numerous other physical analytical techniques presented within this volume, the physical characterization of a pharmaceutical solid is not complete without vibrational analysis. 

Aluminum wrought alloy 1350, 2 328t overhead transmission line application, 2 341... 

Several case studies will be discussed in this chapter to show the use of and possible implementation methods for the ideas discussed in the previous chapters in a practical environment. The examples of application consist of two industrial cases for which real plant data were available, and an on-line application for the monitoring and control of a distillation column through a distributed control system. 

The SQUID obviously has several potential advantages for on-line applications. It can operate at very low inhomogeneous magnetic fields, avoiding the need for large expensive shimmed magnets. It also does not require tuning and has very low power requirements. However there are also severe technical limitations to be overcome before it can be used in on-line commercial operations. The whole SQUID needs to be immersed in liquid helium and a conventional RF coil is still needed to excite the NMR resonance. It remains to be seen whether such devices will find future on-line application in horticulture. 

Instrnmentation for UV-vis process analysis falls into fonr categories scanning instruments, diode-array instrnments, photometers, and fiber-optic spectrophotometers with photodiode-array (PDA) and charge-conpled device (CCD) detectors. The former two are more typically enconntered in at-line or near-line applications, whereas the latter two are better snited to actnal on-line analyses. 

Of the analytical techniques available for process analytical measmements, IR is one of the most versatile, where all physical forms of a sample may be considered - gases, liquids, solids and even mixed phase materials. A wide range of sample interfaces (sampling accessories) have been developed for infrared spectroscopy over the past 20 to 30 years and many of these can be adapted for either near-lme/at-lme production control or on-line process monitoring applications. For continuous on-line measurements applications may be limited to liquids and gases. However, for applications that have human interaction, such as near-line measurements, then all material types can be considered. For continuous measurements sample condition, as it exists within the process, may be an issue and factors such as temperature, pressure, chemical interfer-ants (such as solvents), and particulate matter may need to be addressed. In off-line applications this may be addressed by the way that the sample is handled, but for continuous on-line process applications this has to be accommodated by a sampling system. 

Vibrational spectroscopy, in the form of mid-IR, NIR and Raman spectroscopy has been featured extensively in industrial analyses, both quality control (QC), process monitoring applications and held-portable applications [1-6]. The latter has been aided by the need for advanced instrumentation for homeland security and related HazMat applications. Next to chromatography, it is the most widely purchased classihcation of instrumentation for these measurements and analyses. Spectroscopic methods in general are favored because they are relatively straightforward to apply and to implement, are rapid in terms of providing results, and are often more economical in terms of service, support and maintenance. Furthermore, a single spectrometer or spectral analyzer, in a near-line application, may serve many functions, whereas chromatographs (gas and liquid) tend to be dedicated to only a few methods at best. 

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