Flow line layout

Often, instead of using the grouped or flow line layout exclusively, a combination that best suits the specific situation is used. 

The factory has a flow line layout. Subassemblies are manufactured in workstations located on either side of the factory and transported to the centrally located main assembly line using a computer-controlled overhead conveyor system. Subassembly workstations Include ... 

The/low line layout uses the train or line system, which locates all the equipment in the order in which it occurs on the flow sheet. This minimizes the length of transfer lines and, therefore, reduces the energy needed to transport materials. This system is used extensively in the pharmaceutical industry, where each batch of a drug that is produced must be kept separate from all other batches. In other industries it is used mainly for small-volume products.3... 

Fig. 4.4 Schematic layout of gas and liquid flow lines. A, B and C are electropneumatic valves.

Piping Layout Main Process Flow Lines... 

Figure 7-6 shows a plan of the feed gas compressor area for a 200,000 tons per year ethylene unit. Main pipe runs are also shown. It is an In-Line-Layout with equipment in process flow sequence. The large diameter gas lines directly interconnect process equipment. On the complete plot plan, equipment (including compressors) is arranged on both sides of a central yard in process flow sequence. Pumps are located at their point of suction and are lined up under the yard. A parallel road is arranged to every line of equipment for convenient construction and maintenance access. 

Having decided on the basic arrangement of the system components, the next step is the detailed layout of the system. For this purpose, the second type of flow diagram is used, the process flow sheet, which describes the process using defined design marks for apparatus, armatures, and flow lines. This type of diagram contains the following basic information ... 

Schematic of the bipolar plate with serpentine flow channel (a) flow field layout and (b) the cross-sectional view of the bipolar plate and the porous electrode along the line A-A illustrating the cross-leakage flow between the two adjacent flow channels through the porous electrode structure as presented by the thick arrow. (From Kanezaki, T. et ak, 2006. Journal of Power Sources, 162 415-425. With permission.)...

Figure 8. Quickborner Team diagram of communication flow (lines) between work groups (represented by boxes) from which they purportedly planned the layout of an open plan office.

Unit layout as installed is the next step of preparation. This may take some effort if analysts have not been involvea with the unit prior to the plant-performance analysis. The equipment in the plant should correspond to that shown on the PFDs and P IDs. Wmere differences are found, analysts must seek explanations. While a hne-by-line trace is not required, details of the equipment installation and condition must be understood. It is particularly useful to correlate the sample and measurement locations and the bypasses shown on the P IDs to those ac tuaUy piped in the unit. Gas vents and liquid (particularly water-phase) discharges may have been added to the unit based on operating experience out not shown on the P IDs. While these flows may ultimately be small within the context of plant-performance an ysis, they may have sufficient impact to alter conclusions regarding trace component flows, particularly those that have a tendency to build in a process. 

Piping to Burners - First and second stage piping and headers, as well as the burner lines themselves, are sized to minimize pressure drop and velocity effects. Thus, maldistribution of flow to the burners will be minimized. The burner lines are fabricated from standard 1(X) mm pipe, and are arranged in a split grid layout with distribution headers and split feed lines on opposite sides, for both first and second stage burners. First and second stage headers must be sloped so that any condensate will drain back to the seal drums. However, the burner lines must be accurately installed in a horizontal plane. 

Number of cavities, layout and size of cavities/runners/gates/cooling lines/side actions/knockout pins/etc. Relate layout to maximize proper performance of melt and cooling flow patterns to meet part performance requirements preengineer design to minimize wear and deformation of mold (use proper steels) lay out cooling lines to meet temperature to time cooling rate of plastics (particularly crystalline types). 

A better method for the presentation of data on flow-sheets is shown in Figure 4.2. In this method each stream line is numbered and the data tabulated at the bottom of the sheet. Alterations and additions can be easily made. This is the method generally used by professional design offices. A typical commercial flow-sheet is shown in Figure 4.3. Guide rules for the layout of this type of flow-sheet presentation are given in Section 4.2.5. 

The stream line numbers should follow consecutively from left to right of the layout, as far as is practicable so that when reading the flow-sheet it is easy to locate a particular line and the associated column containing the data. 

The basic construction consists of a rectangular or cylindrical steel chamber, lined with refractory bricks. Tubes are arranged around the wall, in either horizontal or vertical banks. The fluid to be heated flows through the tubes. Typical layouts are shown in Figure 12.69a, b and c. A more detailed diagram of a pyrolysis furnace is given in Figure 12.70. 

To minimize contamination or mix-up, a third layout could be basic straight-line flow moving the materials along a critical path. The main advantage over the above-mentioned layouts is minimal crossover of materials, thus minimizing the potential... 

Figure 5.8 Schematic representation of a chip-based solid phase extraction-MEKC device, (a) Layout of the entire device and (b) expanded view of the extraction region of the device. The dotted lines represent the direction of fluid flow during extraction the solid lines signify flow during elution/injection (Narrow channels are 55 pm wide, column chamber is 210 pm wide, with all channels 15 pm deep.) [87].

On-Line Systems Flowing MMLLE systems have been established in different layouts with automation and on-line hyphenation to GC and HPLC analysis. An automated on-line FS-MMLLE-GC system with a loop-type interface compatible with LVI was used for the extraction of pesticides and PAHs in surface waters.86 In another study, pressurized hot water extraction (PH WE) was coupled on-line to a FS-MMLLE-GC-FID system and applied to the analysis of PAHs in soil, where MMLLE was used as a cleanup and concentration step of the PH WE extract prior to final GC analysis.87 In addition, an HF-MMLLE setup was incorporated in PHWE and GC, resulting in an online PHWE-HF-MMLLE-GC system, where the HF membrane module contained 10-100 HFs. The system served for the extraction and analysis of PAHs in soil and sediments ... 

The overall combustor/optical layout is shown in Fig. 3, which illustrates temperature measurement by the Stokes/anti-Stokes method. Typical results for temperature pdf s at four radial positions (2, 7) near the centerline to near the flame boundary - and at an axial distance 50 fuel-tip diameters downstream of the fuel line tip are shown in Fig. 4. The shaded parts of the pdf contours (from 300 to 800°K), which increase in area near the flame boundary, correspond substantially to scattering from ambient temperature air, and therefore provide a measure of flow intermittency. The upper limit of these bins was chosen to be 800°K because the accuracy possible for the Stokes/anti-Stokes temperature measurement method degrades rapidly at temperatures below roughly that value (2,2) Thus, treating the fluctuation temperature data for T < 800 K in any greater detail was unwarranted. 

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