Charts correction

SCALE/CHART CORRECT POWER SUPPLY CORRECT ... 

Without an accurate birth time, you can never know what your Ascendant is (see Chapter 11 for more about Ascendants). You won t have trustworthy house placements for your planets. You may not even know your Moon sign because it changes signs every two or three days. Without an accurate birth time, interpreting your chart correctly will be challenging. And predicting the future will be close to impossible. 

An accurate method would use available heat charts corrected for dissociation such as from reference 52, figure 9.7 and 13.4a, or figures 5.1 and 5.2 in this book, which give the following answers for a natural gas analysis of 90% methane (CH4), 5% ethane (CaHe), 1% propane (CsHg), and 4% nitrogen (N2), with 1800 F exit gas ... 

The Coulter data was read from the chart, corrected for the offset of 3 and plotted. A spline curve is shown fitted to these points in the figure. The HIAC data was transformed to the same scale for comparison and is shown in the figure as individual data points. Agreement of the distributions around the maximum are excellent The HIAC data shows a significant number of particles in the <18pm region where data is not given for the Coulter. This is above the noise level of the system and is believed to be due to smaller contaminant particles in the calibration standard as used after extensive dilution. 

Scale/chart correct Powo supply correct 1... 

In preparation for a field wide quick look correlation, all well logs need to be corrected for borehole inclination. This is done routinely with software which uses the measured depth below the derrick floor ( alonghole depth below derrick floor AHBDFor measured depth , MD) and the acquired directional surveys to calculate the true vertical depth subsea (TVSS). This is the vertical distance of a point below a common reference level, for instance chart datum (CD) or mean sea level (MSL). Figure 5.41 shows the relationship between the different depth measurements. 

After the melting point has been determined, the thermometer reading is corrected by reference to the calibration chart of the thermometer. Methods for calibrating a thermometer are described in Section 11,9. 

These charts have the parameter curves superimposed on the standard M I L) correction factor curves. Thus the four pertinent groups, P, R, T, and -N, are displayed together on the same chart. The design calculation is thus reduced to finding F and A/, given P and R the performance calculation is reduced to finding F and P, given R and N. ... 

Pareto charts often illustrate the principle that 80% of the effect is the result of 20% of the causes (49). Thus these charts are valuable in prioritizing improvement activities. Identifying and correcting the 20% often results in an 80% improvement in the measured effect. 

Another property which can be represented by generalized charts is fugacity, ( ). The fugacity of a substance can be regarded as a corrected vapor pressure. At low pressures (below atmospheric) the use of pressure in the place of fugacity leads to tittle error in calculations. The fugacity coefficient is defined by... 

Actual progress made with construction work can be indicated on the bar chart by filhng in the open bars according to the percentage toward completion. Comparison of the actual progress bar for the whole project with the cumulative labor-hour curve indicates whether the job is ahead of schedule or not. If corrective action is required, effort should be concentrated on the key or critical items. 

The chart shown in Fig. 10-25 is for pure liqmds. Extrapolation of data beyond the ranges indicated in the graph may not produce accurate results. Figure 10-25 shows the variation of vapor pressure and NPSH reductions for various hydrocarbons and hot water as a function of temperature. Certain rules apply while using this chart. When using the chart for hot water, if the NPSH reduction is greater than one-half of the NPSH reqmred for cold water, deduct one-half of cold water NPSH to obtain the corrected NPSH required. On the other hand, if the value read on the chart is less than one-half of cold water NPSH, deduct this chart value from the cold water NPSH to obtain the corrected NPSH. 

Example 1 NPSH Calculation Suppose a selected pump requires a minimum NPSH of 16 ft (4.9 m) when pumping cold water What will he the NPSH limitation to pump propane at 55 F (12.8 C) with a vapor pressure of 100 psi Using the chart in Fig. 10-25, NPSH reduction for propane gives 9.5 ft (2.9 m). This is greater than one-half of cold water NPSH of 16 ft (4.9 m). The corrected NPSH is therefore 8 ft (2.2 m) or one-half of cold water NPSH. 

When flanges are attached to one or both ends, the values of k and shall be corrected by the factors Ci, which can be read directly from Chart B, entering with the computed h. 

Acceptable comprehensive methods of analysis are analytical, model-test, and chart methods, which evaluate for the entire piping system under consideration the forces, moments, and stresses caused by bending and torsion from a simultaneous consideration of terminal and intermediate restraints to thermal expansion and include all external movements transmitted under thermal change to the piping by its terminal and intermediate attachments. Correction factors, as provided by the details of these rules, must be applied for the stress intensification of curved pipe and branch connections and may be applied for the increased flexibihty of such component parts. 

Correction-factor charts are also available for exchangers with more... 

Many other MTD correction-fac tor charts have been prepared for various configurations. The Ff charts are often employed to make approximate corrections for configurations even in cases for which they are not completely vahd. 

FIG. 11-4 (Continued) LMTD correction factors for heat exchangers. In all charts, fi = (Ti — T<>y(U — t ) and S = (to — ti)/(Ti — ti). ( ) Cross-flow (drip type), two horizontal passes with U-hend connections (trombone type). (/) Cross-flow (drip type), helical coils with two turns. 

Use of Psychrometric Charts at Pressures Other Than Atmospheric The psychrometric charts shown as Figs. 12-1 through 12-4 and the data of Table 12-1 are based on a system pressure of 1 atm (29.92 inHg). For other system pressures, these data must be corrected for the effect of pressure. Additive corrections to be apphed to the atmospheric values of absolute humidity and enthalpy are given in Table 12-2. 

A given humidity chart is precise only at the pressure for which it is evaluated. Most air-water-vapor charts are based on a pressure of 1 atm. Humidities read from these charts for given values of wet- and diy-bulb temperature apply only at an atmospheric pressure of 760 mmHg. If the total pressure is different from 760 mmHg, the humidity at a given wet-bulb and dry-bulb temperature must be corrected according to the following relationship. 

Feed analyses in terms of component concentrations are usually not available for complex hydrocarbon mixtures with a final normal boihng point above about 38°C (100°F) (/i-pentane). One method of haudhug such a feed is to break it down into pseudo components (narrow-boihng fractions) and then estimate the mole fraction and value for each such component. Edmister [2nd. Eng. Chem., 47,1685 (1955)] and Maxwell (Data Book on Hydrocarbons, Van Nostrand, Princeton, N.J., 1958) give charts that are useful for this estimation. Once values are available, the calculation proceeds as described above for multicomponent mixtures. Another approach to complex mixtures is to obtain an American Society for Testing and Materials (ASTM) or true-boihng point (TBP) cui ve for the mixture and then use empirical correlations to con-strucl the atmospheric-pressure eqiiihbrium-flash cui ve (EF 0, which can then be corrected to the desired operating pressure. A discussion of this method and the necessary charts are presented in a later subsection entitled Tetroleum and Complex-Mixture Distillation. ... 

The theoretical steam rate (sometimes referred to as the water rate) for stream turbines can be determined from Keenan and Keyes or Mollier charts following a constant entropy path. The theoretical steam rate is given as Ib/hr/kw which is easily converted to Ib/hr/hp. One word of caution—in using Keenan and Keyes, steam pressures are given in PSIG. Sea level is the basis. For low steam pressures at high altitudes appropriate coirections must be made. See the section on Pressure Drop Air-Cooled Air Side Heat Exchangers, in this handbook, for the equation to correct atmospheric pressure for altitude. 

Trouble Chart Readings Apparentiy Not Correct or Not Consistent with Local Gauges. 

Figure 5-29. Methods of piping. To find A, multiply the number of diameters of straight pipe from the chart in Figure 5-28 with the appropriate correction factor. Courtesy of Elliott Company ...

The chart given in Figure 16 can be used in the following manner in order to size a relief valve for liquid service. First, determine the area required, A, without any viscosity correction (i.e., for K = 1). Then select the next larger standard orifice size from manufacturer s literature. Determine the Reynolds number, based on the following definition ... 

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