Pump testing techniques

The experimental development procedure for pumps includes the following kinds of tests models test in water and air tests of individual items on special rigs pilot tests in water and, finally, pilot tests in sodium. 

From model tests (at scales fi om 1 2.2 for the BOR-60 pumps to 1 6.6 for BN-600) the following data were determined  

The most important stage in pump development was the testing of prototype pumps in water and sodium. Hydraulic and cavitation characteristics of the pumps, mechanical and power parameters of the motors, hydraulic axial and radid forces, and vibration intensity were determined. Operability under start-up, transient and anticipated emergency conditions was tested. 

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In my talk I surveyed recent advances in the methodology and selected 2D-IR spectra of secondary structures. The results promise to provide structurally based kinetic probes for conformational dynamics, sharp tests of anharmonic potential surfaces and novel information regarding the transient and equilibrium vibrational dynamics of peptides. The heterodyned 2D-IR approach has proven useful in determining structures of peptides in solution and the anharmonic nature of the potential surfaces of peptides and secondary structures [1-10], as have polarized photon echo [2,6,10-12] or pump-probe techniques [4,13-16]. 

By exploiting the microdialysis technique, the miniaturization of the whole instrumentation was achieved, also through the use of a peristaltic pump which turned out to be the only type of pump suitable for coupling to an electrochemical cell. The high sensitiviiy of the latter, in fact, revealed that all the syringe pumps tested were not really pulse-free . 

Determination of the permeability in the field can be done by measuring the time it takes for a tracer to move between two test holes. As with pumping tests, this tracer technique is based on the assumption that the aquifer is homogeneous and that observations taken radially at the same distance from the well are comparable. This method of assessing permeability requires that injection and observation wells be close together (to avoid excessive travel time) and that the direction of flow be known so that observation holes are correctly sited. 

Range 1 of the mud pump performance characteristic is defined by the performance of the smallest liner, and range 2 is defined by the remaining liners. The pressure loss in a circulating system, except for bit (p ), can be estimated from numerous theoretical formulas or from a flowrate test. Data obtained from a flowrate test can be approximated using a curve-fitting technique by the following function ... 

Other methods of adjusting the output while keeping the speed constant consist of modifying the profiles of the blades at the maximum diameter of the impeller. This technique has been used for a long time and is often used to obtain a small energy rise when the pump is down on performance when tested. The reader is referred to reference 2. 

Factory tests establish the pressure head, power, efficiency and NPSH over the complete flow range the pump can deliver running at design speed. British Standard, DIN standard or ANSI standard codes or national variations from such main codes lay down the manner of test procedure, and a minimum requirement is quite often defined by industry codes such as API 610. This is not the place to discuss instrument accuracy, as the codes lay down the limits possible from conventional instruments. There are two main classes of test the commercial requirements normally possible in the maker s test plant and high-accuracy tests that are only possible by using substandard instruments and very sophisticated techniques. 

Backflushing of injected wastes can also be a good way to observe waste/reservoir geochemical interactions. Injected wastes are allowed to backflow (if formation pressure is above the elevation of the wellhead) or are pumped to the surface. Backflowed wastes are sampled periodically (and reinjected when the test is completed) the last sample taken will have had the longest residence time in the injection zone. Keely165 and Keely and Wolf166 describe this technique for characterizing... 

Conventional pump-and-treat techniques are not very effective in restoring aquifers impacted by DNAPLs. This ineffectiveness is a result of the relatively low solubility of the DNAPL and the large capillary forces that immobilize the nonaqueous phase. Over the past decade, several innovative and experimental strategies have been tested for more effective recovery of DNAPLs. These strategies include the more conventional use of surfactants, and thermally enhanced extraction or steam injection. Other more experimental approaches include cosolvent flooding and density manipulations. Each of these approaches is discussed below. 

The rotational relaxation of DNA from 1 to 150 ns is due mainly to Brownian torsional (twisting) deformations of the elastic filament. Partial relaxation of the FPA on a 30-ns time scale was observed and qualitatively attributed to torsional deformations already in 1970.(15) However, our quantitative understanding of DNA motions in the 0- to 150-ns time range has come from more accurate time-resolved measurements of the FPA in conjunction with new theory and has developed entirely since 1979. In that year, the first theoretical treatments of FPA relaxation by spontaneous torsional deformations appeared. 16 171 and the first commercial synch-pump dye laser systems were delivered. Experimental confirmation of the predicted FPA decay function and determination of the torsional rigidity of DNA were first reported in 1980.(18) Other labs 19 21" subsequently reported similar results, although their anisotropy formulas were not entirely correct, and they did not so rigorously test the predicted decay function or attempt to fit likely alternatives. The development of new instrumentation, new data analysis techniques, and new theory and their application to different DNAs in various circumstances have continued to advance this field up to the present time. 

With this procedure, as with the double-resonance methods in atomic physics, Zeeman and Stark splittings, hyperfine structures and A doublings in molecules can be measured with high precision, even if the observed level splittings are far less than the optical dopp-ler width. From the width of the rf resonance and from the time response of the pumped systems, orientation relaxation rates can be evaluated for individual v J") levels. Other possible applications of this promising technique have been outlined by Zare 30) Experiments to test some of these proposals are currently under investigation and their results will be reported elsewhere. 

Where a vacuum is present inside the test specimen (p < 1 mbar), atmospheric pressure outside, and helium is used at the test gas, one refers to standard helium conditions. Standard helium conditions are always present during helium leak detection for a high vacuum system when the system is connected to a leak detector and is sprayed with helium (spray technique). If the specimen is evacuated solely by the leak detector, then one would say that the leak detector is operating in the direct-flow mode. If the specimen is itself a complete vacuum system with its own vacuum pump and if the leak detector is operated in parallel to the system s pumps, then one refers to partial-flow mode. One also refers to partial stream mode when a separate auxiliary pump is used parallel to the leak detector. 

The use of laser-induced fluorescence (LIF) for tropospheric HO and H02 measurements was reported by Hard and co-workers (108-110), who developed a fluorescence technique based on pumping the air sample into a low-pressure cell (FAGE) and exciting it with a copper vapor laser-pumped dye laser with a high repetition rate. Their H02 measurements were not made in conjunction with enough other supporting measurements to allow an accurate test of photochemical models from the results. 

Infrared thermographic techniques can be used to identify hot spots on process equipment The camera works on the theory that the hotter the object, the higher the frequency of radiation. For off-line corrosion monitoring, horoscopes for inspecting tubes, pumps, compressors, and other equipment may be used. Spot chemical testing can indicate the... 

A tube (length 1.5 m and volume 4 ml) was inserted in front of the injector and placed in a thermostat in order to ensure good temperature control of the mobile phase. 25 ml of an aqueous perchlorate solution was present as a separate layer in the solvent reservoir in order to keep the mobile phase saturated. The column coating was achieved by the pumping technique. Columns were first tested in the adsorption mode with n-hexane + 1-butanol (199 + 1)... 

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