Pressure recording

In some cases when drilling fluids invade a very low permeability zone, pressure equalisation in the formation can take a considerable time. The pressure recorded by the tool will then be close to the pressure of the mud and much higher than the true formation pressure. This is known as supercharging. Supercharging pressures indicate tight formation, but are not useful in establishing the true fluid pressure gradient. 

Permanent downhole pressure recording is becoming more common tor critical wells. 

Control of Dyeing Equipment. Over the years, the dyer and machinery manufacturer have appHed any mechanical or electrical equipment that would enable them, day after day, to produce repeatable dyeings of top quaHty. First, thermometers were installed in dye lines these soon evolved into thermocouples with remote recording. Other improvements were soon developed, such as automatic four-way valves with variable-interval controls, flow controls, pressure recorders, hydrauHc and air pressure sets on roUers, pH controls, etc. 

Flow Low mass flow indicated. Mass flow error. Transmitter zero shift. Measurement is high. Measurement error. Liquid droplets in gas. Static pressure change in gas. Free water in fluid. Pulsation in flow. Non-standard pipe runs. Install demister upstream heat gas upstream of sensor. Add pressure recording pen. Mount transmitter above taps. Add process pulsation damper. Estimate limits of error. 

Absolute pressure The pressure recorded relative to the absolute zero value of pressure. 

Manometer pressure The pressure recorded on a manometer, measured in Pa or mm water gauge. 

Total pressure The algebraic sum of the velocity and static pressure, recorded at a set position within the system. 

Pressure recording controller, pneumatic transmission with board niotmted receiver... 

Pressure recording controller (differential), pneumatic transmission with pressure recorder, combined instrument board mounted... 

Flow recorder, meclianical type, with direct connected pressure recording pen, locally mounted. (Note llial in listing such a combination item in speeifications, etc., it would be written as FR-4 and PR-2, thereby treating each element as a separate entity)... 

Flow recorder with pressure recording pen, botli elements pneumatic transmission, Iransmiller local, and receiver board mounted. (Recei er should be written as FR-5 and PR-2, and each transmitter identified by its own element)... 

Assuming no cutting in the annulus, compute the pressure recorded inside the drill collars downhole and the pressure in the standpipe at surface using the formula given hereafter. 

I he flowrate of air at 298 K in a 0.3 m diameter duct is measured widi a pilot tube which is used (o traverse the cross-section. Readings of the differentia) pressure recorded on a water manometer are taken with the pitot tube at ten different positions in the cross-section. These positions are so chosen a to be the midpoints of ten concentric annuli each of the same cross-sectional area. The readings are ... 

The flowrate of air in a 305 mm diameter duct is measured with a pitot tube which is used to traverse the cross-section. Readings of the differential pressure recorded on a water manometer are taken with the pitot... 

The relationship between temperature and pressure holds true only in the presence of pure steam adulteration with air contributes to a partial pressure but not to the temperature of the steam. Thus, in the presence of air the temperature achieved will reflect the contribution made by the steam and will be lower than that normally attributed to the total pressure recorded. Addition of further steam will raise the temperature but residual air surrounding articles may delay heat penetration or, if a large amount of air is present, it may collect at the bottom of the sterilizer, completely altering the temperature profile of the sterilizer chamber. It is for these reasons that efficient air removal is a major aim in the design and operation of a boiler-fed steam sterilizer. 

Static Chemisorption. Measurements were made by two procedures. In the first, the catalyst was evacuated at ca. 250°C for at least 8 hrs and cooled to the measurement temperature under vacuum. Hydrogen was then admitted at progressively higher pressures and the amount of gas adsorbed after 15-30 min at each pressure recorded. The sample was then evacuated for 30 min and the dosing procedure repeated so as to obtain a measure of the reversibly adsorbed gas. In the second (saturation) procedure, after reduction and evacuation, the catalyst was cooled to the... 

Cardiopulmonary support must be instituted and adjusted rapidly. Electrocardiogram (ECG) monitoring, continuous pulse oximetry, urine flow monitoring, and automated blood pressure recording are necessary. Peripheral or femoral arterial catheters may be used for continuous assessment of arterial pressure. 

Figure 11. Typical Pressure Record from an Internal Explosion in a Vented Structure.

Their pressure records at the beginning of the reaction show that no induction period similar to that observed during the pyrolysis of monosilane occurs. This suggests that the overall reaction... 

In all thermoanalytical investigations it is very important how the substance is placed and positioned on the sample holder. This was illustrated in simultaneous TG-DTA measurements in connection with gas analytical investigations by Wiedemann42. The three profiles shown in Fig. 37 correspond to the water vapor pressures recorded with a mass spectrometer during thermal dehydration of fine-grained calcium... 

Fig. 11. Changes In gated NMR spectra during the cardiac cycle. Top panel isovolumic left ventricular pressure In a ferret heart paced at 0.99 Hz in 8 mM [Ca +]. NMR spectra were acquired at the two times indicated on the pressure record (a) 10 ms prior to stimulation (b) 75 ms after stimulation. Middle panel shows gated F NMR spectra (each from 800 acquisitions) recorded at (a) and (b), as indicated. The bound (B) and free (F) peaks of 5F-BAPTA exhibit distinct chemical shifts at approximately 8 and 2 ppm, respectively, downfield from a standard of 1 mM 6-Ftryptophan at 0 ppm. It appears that the free [Ca +] varied during the cardiac cycle. Bottom panel shows gated P spectra (400 scans) acquired at times a and b in the same heart. The major peaks correspond to phosphocreatine (0 ppm), ATP (the three peaks upfield from phosphocreatine), and inorganic phosphate (the small peak at 4-5 ppm) (Reproduced from Marban et al. Circ. Res. 1988 63 673-678 [311] with permission of Lippincott, Williams Wilkins).

Near these limits there was always a "spin in the deton, which appeared on the pressure record as a periodic oscillation of the pressure for some distance behind the wave front] 14) G.B. Kistiakowsky, IEC... 

The course of the pressure during a decomposition occurring in a vessel of 10 m3 volume is presented in Fig. 7.2-1, left [1]. Within 1 s the pressure increases from 18.5 to 30.8 MPa. The peak pressure exceeds the range of the pressure-recording device. Extrapolation of the data... 

To lower the tower pressure, the hot-vapor bypass pressure recorder controller (PRC) valve is closed. This forces more vapor through the condenser, which, in turn, lowers the temperature in the reflux drum. As the liquid in the reflux drum is at its bubble point, reducing the reflux drum temperature will reduce the reflux drum pressure. As the stripper tower pressure floats on the reflux drum pressure, the pressure in the tower will also decline. 

Figure 7. Flow and instrumentation diagram for high temperature, balanced pressure bench-scale unit. LR, level recorder LT, level transmitter TR, temperature recorder FR, pressure recorder FR, flow recording RD, densitometer PC, pressure controller TC, temperature controller GM, gas meter F, filter VSD, variable speed drive PCV, pressure regulator CV, control valve SV, solenoid valve S, gamma ray source.

Figure 4. Blood Pressure Records from Anesthetized Cat before and following Administration of Adrenolytic Agent...

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