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As the fundamental documents (apart from the process flow diagrams) of any sound chemical/process engineering designs, piping and instrumentation diagrams (P&IDs) are arguably in terms of effort, the most demanding, current technology allows the use of computer programs and databases to construct an accurate and detailed flowsheet. This may be a process type diagram or a piping and mechanical/instrument diagram, depending on the input, electrical structural, and so on.

Table 14.2 Three programs offer a different mix of features.

	Procede	AutoPLANT	CADPIPE
AutoCAD required	No	Yes	Yes
Automatic line breaks for symbols	Yes	Yes	Yes
Automatic line clash	Yes	Yes	Yes
Rotate command required for symbols	No	No	Yes
Specification checking available	No	Yes	Yes
Dual automatic tagging	No	Yes	Yes
Data form with secondary tag	No	No	Yes
Automatic signal connect	No	Yes	No

Source: J.L. Viola [12].

Figure 14.15 (a) Computer-generated P & ID flowsheet [9] (b) Computer-generated instrumentation detail for P & ID flowsheet [9].

Since the advent of computer aided design (CAD), most notably represented by AutoCAD, several software packages have been more recently introduced for piping, structural, mechanical, and process drawings. These software packages conform to the chemical process industries standard techniques that are common to most process designs. For examples, the use of universally recognizable symbols for pumps, compressors, vessels and tanks, piping, and valves, and the acceptance of Instrument Society of America (ISA) standard symbols to describe instrumentation. These software packages (e.g., VISIO, CADPIPE, AutoPLANT, and PROCEDE) provide users via “pull-down” menus extensive symbol libraries and provide lists and graphics of the components that are required to produce P&IDs, and piping isometrics. Viola [12] has reviewed three of these software packages, and Table 14.2 shows the key features of these packages. See Figures 14.8, 14.9, 14.15a, and 14.15b.

Recently, intelligent P&IDs are being incorporated in plant operations, where in the past P&IDs were hard copy drawings that were computer aided design (CAD) products. The latest generation of intelligent P&IDs uses software that incorporates commercial databases, thus allowing ease of integration to other applications such as calculation packages, inclusion of “smart objects,” data sheet information, ease of use and additional features that surpass CAD deliverables of P&IDs. Novak [13] provides the advantages of incorporating intelligent P&IDs during engineering procurement construction (EPC) phases in terms of reduced capital expense by lowering project costs and improved engineering and design work flow and time to the market. Intelligent P&IDs software enhances database access by separate design teams worldwide for concurrent engineering; its uses during procurement and construction phases include integrating with material management programs, easy creation of subcontractor packages and tracking of as-built changes. Table 14.3 illustrates a number of uses of intelligent P&IDs by operations, resulting in significant return on investment (ROI).

Table 14.3 Uses of intelligent P&IDs by operations.

Provides high integrity of P & ID data—no need to field verify for decision support	Integration with other operations supports software such as reliability solutions. Plant management (PM) or turnaround planning.
Provides fast access to accurate, current data to aid troubleshooting	Aids in planning and executing emergency or maintenance procedures.
Allows change filtering and recording of updates to meet regulatory compliance	HAZOP analysis for safety checks and audit trails for OSHA, EPA and other compliance initiatives.
Shortened commissioning times	Risk-based inspection and critical system documentation.
Data filtration helps evaluate operational costs related to design scenarios	Production adjustments/reanalysis of process for feedstock variances.
Quicker startups	Allows multiple locations to view P & ID data.

Source: Novak [13] By permission from Hydrocarbon Processing.