Skirt Design

After the skirt and bearing plate have been designed, the skirt design should be cheeked for the rt action of the bolting chairs or ring. (See sefrtipn 10.1 g.)... 

Because the compressive stress is larger than the tensile stress, it usually controls the skirt design and is kept below the skirt s allowable axial compressive stress as given by Eq. 8.15. 

Integral pipe attachments are welded directly to the pipe and are usually of special design. They are used in high temperature services, with moderate or severe loads, and in conjunction with supports, braces, and restraints where rigidity with the pipe shell is desired. Integral attachments may be grouped into five types ears, lugs, shoes, cylindrical tmnnions, and skirts (see Fig. 8). 

A cylindrical polypropylene bottle is used to store a liquid under pressure. It is designed with a 4 mm skirt around the base so that it will continue to stand upright when the base bulges under pressure. If the diameter of the bottle is 64 mm and it has a uniform wall thickness of 2.5 mm, estimate the maximum internal pressure which can be used if the container must not rock on its base after one year. Calculate also the diameter change which would occur in the bottle after one year under pressure. 

The NAO design uses a perforated (bubbler) plate with a skirt and bypass gap in case the bubble holes (about A-inch in diameter) get plugged. The design includes a minimum of 6 inches of liquid seal above the bubbler plate, and the gas superficial velocity is limited to 1 to 3 ft/s. 

OD. Ht. or Lnth. Gallons Shell Head Soddle Skirt Supp t. Shell a Heads Saddle Skiff Supp t. Oper n Design Test Oper n Design ... 

The FRI cap has a plain skirt however, we also manufacture caps with various cap slot designs. Caps and risers can also be offered to our clients specific requirements. 

If the anode is immersed to 30 cm, the wetted area is 330 cm2. To make things simple, we view the skirt as blocking off enough area to reduce the wetted area to 300 cm2. This design worked satisfactorily at 200 mA cm-2 and fairly well at 300 mA cm"2. A laboratory-scale version of the design worked well at 600 mA cm"2, but cell cooling capacity limited operation to tens of minutes. 

Figure 13.23. Typical skirt-support designs (a) Straight skirt (b) Conical skirt...

The skirt thickness should be such that under the worst combination of wind and dead-weight loading the following design criteria are not exceeded ... 

Design a skirt support for the column specified in Example 13.3. 

Try a straight cylindrical skirt (9S = 90°) of plain carbon steel, design stress 135 N/mm2 and Young s modulus 200,000 N/mm2 at ambient temperature. 

Keep the skirt thickness the same as that calculated for the cylindrical skirt. Highest stresses will occur at the top of the skirt where the values will be close to those calculated for the cylindrical skirt. Sin 80.5° = 0.99, so this term has little effect on the design criteria. 

The main load carried by the brackets will be the weight of the vessel and contents in addition the bracket must be designed to resist the load due to any bending moment due to wind, or other loads. If the bending moment is likely to be significant skirt supports should be considered in preference to bracket supports. 

Very high velocities tend to skim the liquid film off the vessel wall and off the liquid at the bottom. The liquid also tends to creep up the wall and down the exit pipe where it is picked up by the exit gas. The skirt shown on Figure 18.9 is designed to prevent reentrainment of the creeping liquid, and the horizontal plate in Figure 18.10 prevents vortexing of the accumulated liquid and pickup off its surface. 

FIG. 14-82 Fabricated costs and installation time of towers. Costs are for shell with two heads and skirt, but without trays, packing, or connections. (Peters and Timmerhaus, Plant Design and Economics for Chemical Engineers, 4th ed., McGraw-Hill, New York, 1991.)... 

Disc holder Has a dual function First, it holds the disc, and second, its skirt or hood shape determines the opening characteristics of the valve as it forms the huddling chamber. It also determines the flow path and hence can have an influence on the flow coefficient. The design of disc holders is very different from manufacturer to manufacturer. 

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