Section 2 — Documentation Requirements

Requirements for CAD Drawings

IPE Engineering Practice IPE-EP-2-3-1

Document number: IPE-EP-2-3-1 · Section: 2 — Documentation Requirements

1.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

2.0

SCOPE

This Practice covers general drafting requirements for new drawings created by Computer Aided Design (CAD). However, when drawings are drafted manually, this Practice shall be used as the general guideline.

This Practice covers 2D deliverables (drawings) a contractor produces for a given project. The decision of a plastic model versus a 3D computer model for interference checking will be made by the Owner’s Engineer. If a 3D computer model is generated, it becomes part of the project documentation and shall be delivered to the client at the end of the project.

This Practice covers general requirements for the different types of drawings used by IPE.

This Practice shall be used for all projects and drawing revisions.

Any Practice of a general nature may contain conflicts and/or omissions. The contractor shall not attempt to interpret Owner requirements for any item that is not clear or appears to conflict with other Practices. The contractor shall request an interpretation from the Owner’s Engineer before proceeding.

Any deviation to this Practice must be approved by the procedure described in EP 1–1–3. An asterisk (*) indicates that a decision by the Owner or Owner’s Engineer is required.

REFERENCES

The latest edition of the following publications are referred to herein.

STANDARDS AND PUBLICATIONS

DEFINITIONS

• ANSI - American National Standards Institute
• API - American Petroleum Institute
• CAD - Computer aided design.
• CAD Supervisor - IPE employee responsible for all CAD services and drawings at each

plant.

• Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
• Dwg - Drawing.
• Electrical One–Line Diagram - Graphical representation of a power system.
• Instrument Loop Drawings - A drawing that shows all the hardwire and softwire, instruments junction boxes, and console or panel connections necessary for a control loop.
• ISA - Instrument Society of America
• NTS - Not to scale.
• Owner - IPE.
• Owner’s Engineer - A IPE appointed engineer.
• P&ID - Piping and Instrumentation Drawing. A drawing that shows ALL equipment, piping, and instrumentation necessary for a given process.
• PFD - Process Flow Drawing. A drawing that shows only the major equipment, piping, and instrumentation necessary to describe the process.
• PR# - Plant record number.
• Piping Isometric Drawings - A drawing that shows all piping details necessary for construction.
• Plans (Plot Plans, Maps) - Drawings that show an aerial view. The drawings are usually to scale and show placement of all equipment, buildings, roads, and vessels.
• Schematics (Junction Box Layout, Electrical Elementary/Schematic) - A drawing that shows how components are wired together in instrument and electrical applications.
• Seed File - AutoCAD parameters set up for default conditions for various drawing types.

GENERAL REQUIREMENTS

• The Owner has standardized on the computer aided design (CAD) system known as AutoCAD, developed by Auto Desk. The use of any other CAD system shall be subject to approval by the Owner’s Engineer. The data transfer between AutoCAD and the contractor’s CAD systems shall be 100% on all 2D deliverables produced. If a 3D model is generated for interference checking, proper documentation should be delivered in its native software for future use by the client. Intergraph is preferred for 3D models. Any other 3D system requires Owner’s approval.
• (*)The Owner will specify the form in which electronic records shall be supplied by the contractor, and the number of copies required.
• All files shall be transferred to the Owner at project completion.
• The contractor shall supply an electronic drawing directory in a file(s) formatted in ASCII. Hard copy directory is at the discretion of Owner’s Engineer. The drawing directory shall include the following:
• Plant name
• File name
• Drawing number
• Title
• Contractor job number
• Owner job number
• Drawing type
• Project area
• Latest approval date
• Tape or diskette number
• The drawing file name shall be site–specific. In general, the file name shall be the drawing number.
• When recording data, no file shall be split between the two tapes or diskettes.
• To conserve computer storage, cross-hatching shall be minimized.
• Table 1 shall be used as a reference to determine EP requirements for standard text, line type, and symbols.

NUMBERING SYSTEMS

• (*)The drawing numbering system is site–specific. The CAD Supervisor shall specify the numbering system to be used on each project.
• Line numbering systems are site–specific and explained in EP 5–1–5.

PRESENTATION

• (*)All drawings and final plots shall be of suitable quality and legibility when reduced from 24 X 36 to 11 X 17 drawings for inclusion in a bound document or manual. The Owner’s Engineer may request reduced size drawings for review.

• The scale shall be stated on all drawings, in the title block. Where more than one scale is used on the same drawing, the scales shall be indicated against the view to which they apply, and the words “as shown” shall appear in the title block. A drawing that is not to scale, “NTS” shall appear in the title block. All scaled drawings shall be drawn full size, when practical, and scaled when plotted.
• Line weights vary according to the type of drawing and the information contained. Text shall have a line weight of AutoCAD “0”. Lines shall have a line weight of AutoCAD “0.02”.
• The AutoCAD font “ROMAN.SHX” and style name “ROMAN” shall be used.
• For standard text, see Table 2.
• The minimum size for text is 1/8 inch high with a .75 width factor when plotted.
• The minimum size for test on piping isometric drawings shall be 3/32 inch high with a .75 width factor.
• The use of colors and layers will aid in drafting, editing, and viewing.
• Typically colored plots are not mandatory; however if color plotters are available, a colored plot can be made as specified by the Owner’s Engineer.
• Generally, color is used to show different process types and not used to depict line widths.
• The use of layers is unlimited in AutoCAD. The number layers shall be kept practical and the layer name shall be so that it is obvious what is on that layer.

REVISIONS TO DRAWINGS

• In all revamps, the revised part of the drawing shall have a cloud around the revised work.
• All CAD drawings shall be revised on CAD. Hand drawn revisions in lieu of CAD drawings are not permitted.

DRAWING TYPES

• Piping and Instrument Drawing (P&ID)

Supplemental Requirements for P&IDs are in EP 2–3–3.

• Process Flow Diagram (PFD)

Supplemental Requirements for PFDs are in EP 2–3–3.

• Instrument Loop Drawings

Supplemental Requirements for Instrument Loop Drawings are in EP 2–3–3.

• Schematic, Electrical One–Line, and Electrical Elementary/Schematic

Supplemental Requirements for electrical drawings are in EP 2–3–4.

• Plans, Plotplans, and Maps

Supplemental Requirements for Plans, Plot Plans and Maps are in EP 2–3–5.

• Piping Isometric Drawings

Supplemental Requirements for Piping Isometric Drawings are in EP 2–3–6.

• Vendor Equipment Drawings

All vendor drawings shall be supplied in AutoCAD when available.

1.0 TABLES

TABLE 1

REFERENCE TABLE FOR STANDARD TEST WIDTH FACTORS, LINE TYPE, AND SYMBOLS

TABLE 2 STANDARD TEXT

© 2026 Inflection Point Engineering, LLC. All rights reserved.