Injection pressure monitoring

Fluid injection, pressure monitoring, and temperature were controlled by an HP85 microcomputer system. Injections were done at constant flow rate with a Constametric III metering pump, from which the filters were removed. 

One area where MWD would be most useful is drilling safety and, particularly, early gas kick detection and monitoring. Conventional kick monitoring is based on pit gain measurements and all other available surface indication such as drilling rate break, injection pressure variation, etc. 

Parenteral (supraventricular tachyarrhythmias) - For IV use only. Give as slow IV injection over at least 2 minutes under continuous EGG and blood pressure monitoring. An IV infusion has been used (5 mg/hour) precede the infusion... 

A solid state Si(Li) detector is used to maximise the flux of helium-like vanadium transitions, to minimise contamination from undesirable charge states and to monitor dielectronic recombination transitions. A small amount of pure nitrogen gas is leaked into the trap (injection pressure 5x 10 7Torr) to increase the proportion of lower charge states via evaporative cooling. 

Implementation of an on-site computer control unit eliminates the need for mechanical systems, and enables real-time computation of bottomhole pressures. Monitoring techniques and pressure calculation methods vary extensively throughout the service industry. However, the measurable parameters such as surface treating pressure, liquid and gas injection rates, proppant concentration, and slurry temperature are the parameters that must be used to determine the bottomhole pressures. 

Numerous hydraulic tests were carried out, during the various project phases, either in an isolated borehole or between boreholes. Hydraulic experiments consisted of pulse tests, constant head injection and/or extraction and constant rate injection/extraction using borehole intervals delimited in FBX 95001, FBX 95002, BOUS 85.001 and BOUS 85.002 (Figure 1). Both water flow and piezometric level measurements for borehole intervals are available. Continuous pressure monitoring has allowed detecting crosshole responses during pulse testing these have then been used to calibrate the hydraulic conductivities of fractures. 

Resin Transfer Molding (RTM) The RTM system gives high quality surface on both the sides. A relatively low pressure (vacuum to 100 psi) process, RTM makes perfect shapes in 30 min to 1 h. The fabricator generally gel coats one or both mold halves, then lays continuous or chopped strand mat and the core, if used, into the bottom half, and closes the mold. The resin transfers into the mold through injection pressure, vacuum pressure, or both. Cure temperature depends on the resin system used. Heater blankets can heat the mold up to 202°C, if the matrix allows sensors to detect resin flow position in the mold and monitor resin and cure data [98]. 

The indwelling central venous catheter should be maintained as an intravenous life-line. That the catheter should be used exclusively for delivery of the intravenous nutrient solution is inherent in this philosophy. The temptation to withdraw blood via the catheter, to use the catheter for frequent central venous pressure monitoring, to inject bolus medication via the catheter, or to use the catheter for blood or blood constituent administration must be repressed. Three-way stopcocks within the delivery system must be condemned, because maintenance of the sterility of any intravenous system containing a three-way stopcock is virtually impossible. 

Reservoir coimectivity is important to sweep efficiency in all phases of production. How efficiently a formation s pore spaces are coimected is determined through tracer analysis, where chemical or radioactive tracers are introduced at injection and monitored at production wells. The idea is simple the more tracers obtained at a producer, the better the connectivity between the injectors and it. In reservoir simulation, the oilfield s permeability and porosity distributions are determined, often by trial and error, and more than likely nonuniquely, by history matching with production and well test data. In singlephase flow reservoirs, steady-state production profiles are completely determined by the pressure equation and Darcy s law, neither of which depends on porosity. In well testing, pressure buildup and drawdown depend on porosity and compressibility, factors that do not directly enter in steady-state production. Empirical tracer tests provide further information porosity, inferred from tracer travel times, enters in steady flows where compressibility is unimportant. These three flow tests therefore provide good independent check points that are essential to good reservoir description. 

The injectivity test was initiated in August, 1983. Well 152 and two adjacent wells were equipped with surface readout pressure sentries. The two adjacent wells were shut in and used for reservoir pressure monitoring. Polymer injection was initiated using 750 ppm Cyanatrol 970 at 1,500 BWIPD. Pressure falloff tests and swab samples were obtained on 8/24/83 (4,447 bbl polymer injected), 9/12/83 (25,580 bbl), and 10/6/83 (67,398 bbl). 

Careful pressure monitoring indicates that injectivity is still excellent, and no impairment has been observed after the high overall volume of polymer injected. 

One of the most surprising ways to affect the dimensions of an injection-molded part is to vary the injection pressure hold time. Generally, the injection pressure is applied and then released after a specified time to allow the injector to recharge for the next shot. Releasing the injection pressure early versus late can have a profound effect on the dimensions of the finished part. This has been observed many times but has not yet been thoroughly studied or quantified. However, on large diameter parts such as O-Rings, this can be the difference between dimension-ally compliant and dimensionally rejected parts. In the initial setup of the injection process, injection pressure hold time should be a variable studied for its effects on the finished parts. If the relationship of injection hold time is established in the initial production approval process, it is more likely to be monitored and controlled in routine production. 

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