Layout piping

Paton [15] reports total model costs of 0.4 to 1.0 percent of erected plant costs for a 1 million plant. These are actual costs and do not reflect profits. Material costs are less than 10 percent of total model costs, and usually less than 5 percent. For a. 30 million plant model costs run as low as 0.1 percent. These are for models which include plant layout, piping layout, and piping details. If simpler models are used the costs should be less. 

Evaluate operation and maintenance costs as well as potential impact on layouts, piping, and spare parts inventories. 

Fio. 9-6. Scale layout piping. ( . E. French and C. J. Vierck by permission from A Afanttal of Engineering Drawing, 8th ed., AfcGrato-Hill Book Company, Inc., New York.)... 

Design and layout of the separation unit (foundation plan, arrangement layout, piping... 

Considering the difficulties of co-ordination faced by a multidisciplinary design team, and the need to minimize design iterations by foreseeing the whole eventual plant when preparing initial layouts, pipe support systems should be substantially set out for batches of lines from the outset for example, pipes should be run on racks whenever possible. 

Flexibility Through Layout Piping is rarely run in a straight line from one fixed connection point to another. Each time piping changes direction and is left free to move at the point of change, the system becomes more flexible. By making bends in more than one plane the flexibility is further enhanced. 

Plant flow diagram Document for operating conditions Plant layout Piping diagram (if any)... 

Preliminary plant layout, pipe sizes, and holding tanks... 

The layout, piping and pipeline route plans can be generated together or separately, depending on which components or systems are hidden or displayed in the CAD system. As already mentioned, any views and sections can be selected and plotted. 

There are several other batch processes. Vacuum bag and resin injection techniques have been used for specialist application but these are not used extensively in commercial practice. Centrifugal casting has been used for the manufacture of pipe sections but this is again a specialised area. Filament winding (Fig. 3) is essentially a batch process but by good engineering and well planned layout, pipes and tanks made by the filament winding process can be produced... 

Although equipment types and the flow of process streams between the equipment types are the main drivers in plant layout, piping is also important—not least because it constitutes a major part of the overall cost of the complete facility. 

A cost-effective layout that provides for easy operabiUty and quick turnarounds is often designed by someone with a background in the piping discipline. This is most likely because of their abiUty to think in three dimensions and their familiarity with visualizing three-dimensional piping (see Piping systems). 

The layout can only be started after a process flow diagram is available. The process flow diagram includes information such as the principal equipment items and order of the process flow. A sized equipment Hst is also useful from the standpoint of knowing what spaces are required to fit the equipment. Availabihty of a preliminary piping and instmmentation drawing (P ID) provides more information to aid in spacing equipment and thinking about piperack requirements. 

Fig. 3. Rough layout sketch (/) the two fined heaters F-1 and F-2 are located together but are separated from the other equipment with a subpipeway connecting the process area to the heater area (2) the reboiler E-2 is located adjacent to its column, T-1. The preheat exchanger E-4 is located adjacent to tower T-3 (J) the elevated overhead condenser E-3 is located next to the overhead accumulator V-1. Also, the ain condenser EE-3 is located adjacent to its overhead accumulator V-2 (4) the rest of the ain coolers (EE-1—3, -5) are grouped together ia a common fan stmcture (5) all equipment and related piping is routed to and from the existing piperack saving the addition of a new piperack (6) all pumps (P-1—P-6) are located ia a row under the piperack, and each...

Space needs to be provided for the auxiliaries, including the lube oil and seal systems, lube oil cooler, intercoolers, and pulsation dampeners. A control panel or console is usually provided as part of the local console. This panel contains instmments that provide the necessary information for start-up and shutdown, and should also include warning and trouble lights. Access must be provided for motor repair and ultimate replacement needs to be considered. If a steam turbine is used, a surface condenser is probably required with a vacuum system to increase the efficiency. AH these additional systems need to be considered in the layout and spacing. In addition, room for pulsation dampeners required between stages has to be included. Aftercoolers may also be required with knockout dmms. Reference 8 describes the requirements of compressor layouts and provides many useful piping hints. 

The first five methods are apphcable only after rigorous circuit analysis and when piping layouts and isometric drawings or scale models are available for quantity takeoff (e.g., pipe size, length, and specification, flanges and valve count, etc.). 

Poor suction piping layout, too many elbows in too many planes, a tee branch almost directly feeding the suction of the other pump, or not enough straight run before the suction flange of the pump. 

Redesign piping layout, using fewer elbows and laterals for tees, and have five or more straight pipe diameters before suction flange. 

In general, 50.8- ana 63.4-mm (2- and 2V 2.- n) coils are the most economical for shop fabrication and 38.1- and 50.8-mm Wi- and 2-in) for field fabrication. The tube-side heat-transfer coefficient, high-pressure, or layout problems may lead to the use of smaller-size pipe. 

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