Side wall

Sampling of checkpoints during the review exercise confirmed some predictable features, notably that radiography would miss planar defects such as lack of side wall fusion, and that ultrasonic operators tended not to report undercut, porosity or the smaller slag inclusions. 

Eor drilling, the discharge action occurs at the leading edge of the tool, whereas ECM takes place on the side walls between the tool and the workpiece. The combined spark erosion and ECM action yields fast rates of metal removal. Because ECM is stiU possible, any metallurgical damage to the components caused by the sparking action can be removed by a short period (eg, 15 s) of ECM after the main ECAM action. Currents of 250 A at 30 V are typically used in the process. 

Larger-si2ed heaters are usually hori2ontal box heaters. The radiant coils can be located either on the side walls so that the units are fired from underneath, or in a center row of tubes in which the heater is fired from both sides to provide a higher heat flux for reducing the radiant surface. An access area at one end of the box is required in order to remove the tubes. Sometimes multiple coils are included in the same box, which may require access to both ends of the box. 

Fig. 3. Examples of mass flow bins (a) transition hopper, where 0 is the conical end-wall angle, 0 is the side-wall angle, and BP is the oudet width (b)...

Fig. 4. Examples of expanded dow bins showing where funnel dow becomes mass dow (a) funnel dow cone modified with mass dow transition hopper, where BP = outlet width, DF = diameter, 0 = end-wall angle, and 0 = side-wall angle (b) long funnel dow slot modified with mass dow cones, where...

Furnace Design. Modem carbide furnaces have capacities ranging from 45,000 t/yr (20 MW) to 180,000 t/yr (70 MW). A cross-section of a 40 MW furnace, constmcted in 1981, having a 300 t/d capacity is shown in Figure 2. The shell consists of reinforced steel side walls and bottom. Shell diameter is about 9 m and the height to diameter ratio is shallow at 0.25 1.0. The walls have a refractory lining of 0.7 m and the bottom has a 1-m layer of brick topped by a 1.5-m layer of prebaked carbon blocks. The steel shell is supported on concrete piers and cooling air is blown across the shell bottom. A taphole to withdraw the Hquid carbide is located at the top of the carbon blocks. 

Cracking reactions are endothermic, 1.6—2.8 MJ/kg (700—1200 BTU/lb) of hydrocarbon converted, with heat supplied by firing fuel gas and/or fuel oil in side-wall or floor burners. Side-wall burners usually give uniform heat distribution, but the capacity of each burner is limited (0.1—1 MW) and hence 40 to 200 burners are required in a single furnace. With modem floor burners, also called hearth burners, uniform heat flux distribution can be obtained for coils as high as 10 m, and these are extensively used in newer designs. The capacity of these burners vary considerably (1—10 MW), and hence only a few burners are required. The selection of burners depends on the type of fuel (gas and/or liquid), source of combustion air (ambient, preheated, or gas turbine exhaust), and required NO levels. 

Honzontal-tube cabin heaters position the tubes of the radiant-section-coil horizontally along the walls and the slanting roof for the length of the cabin-shaped enclosure. The convection tube bank is placed horizontally above the combustion chamber. It may be fired From the floor, the side walls, or the end walls. As in the case of its vertical cylindrical counterpart, its economical design and high efficiency make it the most popular horizontal-tube heater. Duties are 11 to 105 GJ/h (10 to 100 10 Btu). 

Identification. Incomplete fusion generally results in discontinuities along the side walls of a joint. When these discontinuities emerge at surfaces, they can be observed visually if accessible (Figs. 15.10 and 15.11). Defects of this type may also be detected by ultrasonics, radiography, magnetic particle inspection, and eddy-current testing. 

Although rod anodes screwed into the side walls of containers are preferred, plate anodes and basket anodes are mostly necessary on the base. They are particularly suitable for large containers without being built in. Plate anodes are supplied with a flat plastic holder to which the cable conductor is attached and... 

The surfaces to be protected should be the total surface, including inserts, spars and pipes. The upper 1.5 m of the side walls and the covers should be provided with a coating of recognized quality [10] to protect against corrosion. 

A tank with a fixed cover of plain carbon steel for storing 60°C warm, softened boiler feed water that had a tar-pitch epoxy resin coating showed pits up to 2.5 mm deep after 10 years of service without cathodic protection. Two separate protection systems were built into the tank because the water level varied as a result of service conditions. A ring anode attached to plastic supports was installed near the bottom of the tank and was connected to a potential-controlled protection rectifier. The side walls were protected by three vertical anodes with fixed adjustable protection current equipment. 

Figure 6. Orifice trough distributor with side-wall orifice, Model 137. (Courtesy of Norton Chemical Process Products Corporation.)...

Not much performance data available, but in general slightly better than Raschig ring, pressure drop slightly higher. High side wall thrust. 

Usually used stacked, and as first layers on support grids for smaller packing above. Pressure drop relatively low, channeling reduced for comparative stacked packings. No side wall thrust. 

Parameters measured Surface topography (rms roughness, rms slope, and power spectrum of structure) scattered light line shape of periodic structure (width, side wall angle, height, and period)... 

Another class of anifacts occurs when scanning vertical or undercut features. As the tip approaches a vertical surface, the side wall may encounter the feature before the end of the tip does. The resulting imj e will appear to contain a discontinuous shift. Changing the angle of the tip with respect to the sample s surface can minimize the problem. Side wall imj ing also occurs in STM, but less frequently since an STM tip has a higher aspect ratio than that of an SFM tip. 

Because of the drag effect of the side-walls of the trough on the expanding and cross-linking foam the process as described above gives a domed block. Hence... 

Much effort has been expended to try and produce flat-top foams. In one process polyethylene sheets placed along the side-walls of the trough rise with the foam. In another technique the reactants are metered from the mixing head into a fixed trough in which partial expansion takes place. The foaming material is then drawn over a weir by a moving band of paper and then drawn down a slope so that the top surface maintains a constant level as the material expands. 

Drying Rooms For drydng materials that cannot be agitated, the drying room, and tray drier (which there are many varieties) can be used. In the former, the material may be spread on pans and these stacked in a rack, which leaves a space between the trays for air circulation. The room has loosely fitted side walls of plaster board, or similar material, or even canvas, and contains a steam radiator. The natural circulation of the warm air removes the moisture the drying period is generally long, for example, one or two days. 

Figure 12. Variation of velocity distribution in a mixing tank on insertion of full side wall baffles.

Remove Free Liquids and Highly Mobile Wastes Stabilize/Repair Side Walls. Dikes or Liner(s)... 

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