Outside diameter

To what we calculated so far, the 65 kV tubes do not necessarily require an outside diameter of 40mm. We want to come down to about 30mm diameter for this voltage, and we plan to extend the voltage range for the existing 65 kV tubes up to 80 or even 100 kV. Higher Stability... 

The surface tension of a liquid is determined by the drop weight method. Using a tip whose outside diameter is 5 x 10 m and whose inside diameter is 2.5 x 10 m, it is found that the weight of 20 drops is 7 x 10 kg. The density of the liquid is 982.4 kg/m, and it wets the tip. Using r/V /, determine the appropriate correction factor and calculate the surface tension of this liquid. 

Wagner and DUlont have described a low-shear viscometer in which the inside diameter of the outer, stationary cylinder is 30 mm and the outside diameter of the inner, rotating cylinder is 28 mm the rotor is driven by an electromagnet. The device operates at 135°C and was found to be free of wobble and turbulence for shear rates between 3 and 8 sec V The conversion of Eq. (2.7) to Eq. (2.9) shows that F/A = (i7)(dv/dr) (instrument constant) for these instruments Evaluate the instrument constant for this viscometer. 

The highly exothermic nature of the butane-to-maleic anhydride reaction and the principal by-product reactions require substantial heat removal from the reactor. Thus the reaction is carried out in what is effectively a large multitubular heat exchanger which circulates a mixture of 53% potassium nitrate [7757-79-1/, KNO 40% sodium nitrite [7632-00-0], NaN02 and 7% sodium nitrate [7631-99-4], NaNO. Reaction tube diameters are kept at a minimum 25—30 mm in outside diameter to faciUtate heat removal. Reactor tube lengths are between 3 and 6 meters. The exothermic heat of reaction is removed from the salt mixture by the production of steam in an external salt cooler. Reactor temperatures are in the range of 390 to 430°C. Despite the rapid circulation of salt on the shell side of the reactor, catalyst temperatures can be 40 to 60°C higher than the salt temperature. The butane to maleic anhydride reaction typically reaches its maximum efficiency (maximum yield) at about 85% butane conversion. Reported molar yields are typically 50 to 60%. 

Commonly used heat-transfer surfaces are internal coils and external jackets. Coils are particularly suitable for low viscosity Hquids in combination with turbine impellers, but are unsuitable with process Hquids that foul. Jackets are more effective when using close-clearance impellers for high viscosity fluids. For jacketed vessels, wall baffles should be used with turbines if the fluid viscosity is less than 5 Pa-s (50 P). For vessels equipped with cods, wall baffles should be used if the clear space between turns is at least twice the outside diameter of the cod tubing and the fluid viscosity is less than 1 Pa-s (10... 

The theoretical value of the coefficient Y ranges from 0 to 1. If V = 0, equation 9 reduces to the Barlow or outside diameter formula. The Barlow formula is always conservative and for large D/1 the error is small. The value Y = 0.4 gives the Boardman approximation of the Lame tangential stress (27)... 

This portion is called springwood (Sp) or eadywood. During the summer or later in the growing season, the cell wall thickness increases to 8—12 pm and the outside diameter decreases from 29—47 pm in short-leaf pine. These cells form summerwood (Sm) orlatewood. The sequential combination of seasonal cell types leads to the characteristic aimual ring (AR) of trees, which is more or less distinct in softwoods, depending on the species. 

A similar relationship guides the change in performance when the impeller outside diameter (OD) is cut ... 

Disk Coupling. Diaphragms are used to transmit torque between the iaside and outside diameters of the flexible element ia disk coupling (Fig. 14b). Up to 0.1-mm (0.004-ia.) parallel misalignment can usually be tolerated. Whereas no oil lubrication is required as compared to gear couplings, disks ate limited to moderate torques. 

Power for each Hquid and the soHd phase must be added to get Pp. P, the soHds process power, = T -AN for scroU decanters, where = conveyor torque and AN = differential speed between bowl and conveyor. Pp is the friction power, ie, loss in bearings, seals, gears, belts, and fluid couplings. P, the windage power, = K and fi = viscosity of surrounding gas p = density of gas D = rotor outside diameter N = rpm and K = shape... 

Pig. 9. Schematic drawiag of a typical stainless steel variable-volume view cell having a movable internal piston. The outside diameter of the cell is 5.08 cm ... 

For practical reasons, the blast furnace hearth is divided into two principal zones the bottom and the sidewalls. Each of these zones exhibits unique problems and wear mechanisms. The largest refractory mass is contained within the hearth bottom. The outside diameters of these bottoms can exceed 16 or 17 m and their depth is dependent on whether underhearth cooling is utilized. When cooling is not employed, this refractory depth usually is determined by mathematical models these predict a stabilization isotherm location which defines the limit of dissolution of the carbon by iron. Often, this depth exceeds 3 m of carbon. However, because the stabilization isotherm location is also a function of furnace diameter, often times thermal equiHbrium caimot be achieved without some form of underhearth cooling. 

Example 5 Radiation in a Furnace Chamber A furnace chamber of rectangular paraUelepipedal form is heated hy the combustion of gas inside vertical radiant tubes hningthe sidewalls. The tubes are of 0.127-m (5-in) outside diameter on 0.305-m (12-in) centers. The stock forms a continuous plane on the hearth. Roof and end walls are refractory. Dimensions are shown in Fig. 5-20. The radiant tubes and stock are gray bodies having emissivities of 0.8 and 0.9 respectively. What is the net rate of heat transmission to the stock by radiation when the mean temperature of the tube surface is SIG C (1500 F) and that of the stock is 649 C (1200 F) ... 

This example will use only SI units, except that pressure will be in atm, not kPa. Flue gas containing 6 percent CO9 and 11 percent H9O vapor, wet basis, flows tbroiigb a bank of tubes of 0.1016 in (4-in) outside diameter on equilateral 0.2032 m (8-in) triangular centers. In a section in wbicb the gas and tube surface temperatures are 691 C (964 K) and 413 C (686 K), what are the emissivity and absorptivity of the gas From Table 5-8, = (2.8)(0.01016) = 0.2845 m (only SI... 

D, Do Outside diameter of pipe mm in Reynolds number Dimensionless Dimensionless... 

With liquids at low velocities, the effect of the Reynolds number upon the coefficient is important. The coefficients are appreciably less than unity for Reynolds numbers less than 500 for pitot tubes and for Reynolds numbers less than 2300 for pitot-static tubes [see Folsom, Trans. Am. Soc. Mech. Eng., 78, 1447-1460 (1956)]. Reynolds numbers here are based on the probe outside diameter. Operation at low Reynolds numbers requires prior calibration of the probe. 

Nominal pipe size, in Outside diameter, in Schedule no. Wall thickness, in Inside diameter, in Cross-sectional area Circumference, ft, or surface, fF/ft of length Capacity at 1-ft/s velocity Weight of plain-end pipe, Ih/ft... 

Nominal pipe size Outside diameter of flange Thickness of flange, minimum Diameter of holt circle Diameter of holts No. of holts Length through huh ... 

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