Design values

The beam index was measured by SORXlOOmm semicircular specimen for SH Wave angle probes. Surface SH Wave probes were considered to be the design value. 

The angle of refraction for SH Wave angle prohes was measured by the peak echo of side drilled holes. But surface SH Wave probes could not be measured, and therefore were assumed to be the same as the design value. 

By attempting to maintain process conditions at or near their design values, the process controls so attempt to prevent abnormal conditions from developing within the process. Although process controls can be viewed as a protective layer, this is really a by-product and not the primaiy func tion. Where the objective of a function is specifically to reduce risk, the implementation is normally not within the process controls. Instead, the implementation is within a separate system specifically provided to reduce risk. This system is generally referred to as the safety interlock system. 

Motor running backward or impeller of double suction design is mounted backward. Discharge pressure developed in both cases is about one-half design value. 

Overhaul pump. Renew wear rings if clearance is about twice design value for energy and performance reasons. 

Change process to adjust specific gravity to design value, or throttle pump to reduce horsepower requirements. This will not correct problem with some vertical turbine pumps that have a flat horsepower-required curve. 

For design, the slip velocity is derated to 70-80 percent of the calculated value to give some margin of safety this sets the design value of the continuous phase velocity (V ). The column cross sectional area (and therefore diameter) is set by QJVc- With the diameter set, the other dimensions can be set using the ratios given above. 

SOURCE Plant data and calculated design values from Rase, Chemical Reac-... 

Nonattainment area classification One-hour ozone concentration design value, ppm Attainment date Major source threshold level, tons VOGs/yr Offset ratio for new/modified sources... 

The measured grounding resistances of the anodes were 6.5 Q for the 24-m-long ring anode and 8 Q for the three 7-m-long vertical anodes and were within the range of the calculated design values. By gradual adjustment of values, the protection potential of the initial protection current density amounted to about 450 /tA m. ... 

An aeeurate determination of rotor thrust balanee losses eould be made by measuring the flow, pressure, and temperature. However, in keeping with the aeeuraey of item 2, Elliott reeommends the use of a ealeulated design value of the horsepower loss. 

Sensitivity to process gas inlet flow. Figure 7-12c shows that TTE is more sensitive to increases in mass flow tlian to decreases. For instance, a 20% increase in mass flow reduces TTE to 94% of the design efficiency, while a 20% decrease reduces TTE to 97% of design value. 

Turboexpander sensitivity to process gas inlet pressure. As previously mentioned, variable speed turboexpanders are more sensitive to changes in normal operating conditions. Tlie pattern of TTE degradation, however, is the same as for constant speed turboexpanders (Figure 7-13a). In other words, TTE is more sensitive to pressure drop than to pressure rise. For instance, a 20% drop in gas inlet pressure will reduce TTE to 90% of the design value, whereas a 20% increase in gas inlet pressure reduces TTE to 99% of the design value. 

From the Finite Differenee method results above, the eontribution of the varianee of eaeh variable to the temperature varianee ean be estimated to foeus in on the key variables bounding the problem. This is an attempt to reduee the thermostat speeifieation toleranee to around half its eurrent design value. 

Title I allows the EPA to define the boundaries of "nonattainment" areas for ozone, CO, and PMjg. Emission standards for these areas will be based on a new set of "nonattainment categories." EPA has established a classification system for ozone design values (goals) and attainment deadlines. Table 24-2 lists these parameters. 

Classification Ozone design values Attainment deadline (from enactment)... 

To determine the deterioration in component performance and efficiency, the values must be corrected to a reference plane. These corrected measurements will be referenced to different reference planes depending upon the point, which is being investigated. Corrected values can further be adjusted to a transposed design value to properly evaluate the deterioration of any given component. Transposed data points are very dependent on the characteristics of the components performance curves. To determine the characteristics of these curves, raw data points must be corrected and then plotted against representative nondimensional parameters. It is for this reason that we must evaluate the turbine train while its characteristics have not been altered due to component deterioration. If component data were available from the manufacturer, the task would be greatly reduced. 

Problem A structured packing vacuum tower had too much heavy key in a vapor side-draw between the feed and the column bottom. The side-draw heavy key concentration was several times the design value. 

While the axial position of multistage impellers to their diffusers is not critical, they should line up reasonably well. Impellers are not extremely sensitive to leading-edge dings and minor damage, but anything, such as erosion on the exit tips, that tends to decrease the effective diameter of the impeller is more serious. Front shroud clearance on open impellers should be maintained close to the design values to minimize capacity loss. 

This represents a shaking force at a frequency equal to rotor speed. For foundation design, a value of 5 to 10 times the residual unbalance or A to 1 times rotor weight at operating speed would be a reasonable design value. The direction of the force is perpendicular to the shaft, and operates as a rotating vector which can be centered between the bearings. 

Range of Test Values Limits—% of Design Value Symbol Min Max... 

Machine Reynolds number where the design value is Re ... 

A common type of distillation contacting device used in refinery applications is the sieve tray. In the early 50 s and for many years before, the bubble cap tray was the mainstay of the distillation field. A sieve tray consists of a flat plate with regularly spaced holes, normally 1/2 to 1 inch in diameter. Liquid flows horizontally across the tray and into a channel, called a downcomer, which leads to the tray below. The sieve tray exhibits good capacity, excellent efficiency, low pressure drop, and good flexibility i.e., it will operate quite efficiently at tower loadings which are 1/2 to 1/3 of design values. 

This equation is based on a negligible wall effect. The design values of P, and Pj must be determined from a scale drawing, which is made to allow the required number of jets to be installed in the available area. This area is restricted by the limitation that no jet should be placed closer than 300 mm from the inside wall of the stack. The spacing is also affected by air flow considerations, which may require the layout to be modified. 

If the space temperature is above its design value, cooling is required. If the space temperature is below the design value, the supply air must be heated. Hence,... 

Environmental temperature A design value used by the CIBSE in heating and cooling calculations, equal to 0.33 6, + 6. ... 

Assume the inlet temperature of regeneration gas is 400°F. In the beginning the initial outlet temperature of the bed will be the bed temperature of 110°F at the end of the heating cycle, the outlet temperature will be the design value of 350°F. So the average outlet temperature is (350 -i-110)/- or 230°F Then the volume of gas required for heating will be... 

V (separator) = Separator vapor velocity evaluated for the gas or vapor at flotving conditions, ft/sec V = Vapor velocity entering unit, lbs, per minute per square foot of inlet pipe cross section Va = Maximum allowable vapor velocity across inlet face of mesh calculated by relation, ft/sec Van Actual operating superficial gas velocity, ft/sec or ft/min, for tvire mesh pad Vu = Design vapor velocity (or selected design value), ft/sec... 

For a given ejector, an increase in steam pressure over the design value will increase the steam flow through the nozzle in direct proportion to the increase in absolute... 

Design values for radiation levels usually used [62] ... 

Select a median value of Fj = 17, because freedom to operate above and below the design value is preferred in this case. 

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