CAD Drafting PID Schematics

Module Title

Description

Introduction

How our learning system works. About CAD (Computer Aided Design) and P&ID drawings. CAD software - AutoCAD and IntelliCAD. Some rules governing the use of symbols and arrangement of P&IDs. Guidance for the creation of P&IDs. Downloading some sample files. Reviewing what we will cover in the course.

The CAD Process

A detailed look at some P&ID drawings. Drafting on paper vs. drafting using CAD software? Some advice on how to learn CAD software. The importance of 'Real World Units'. How to handle scale in CAD drawings. An example of the use of the AutoLISP programming language to speed the drafting process - automating CAD. Some comments on data extraction and creating bills of materials from CAD drawings. The importance of the command area and recognizing that unlike the Microsoft Office suite of applications, AutoCAD and IntelliCAD are command driven programs. The advantages of a 'command driven' CAD program? Setting up AutoCAD and IntelliCAD and adjusting the preferences. Creating an 'intelligent' desktop shortcut to start the program.

The drawing interface

A detailed look at the CAD interface, including the contents of the title bar, the tools on the standard and formatting toolbars, the importance of the command area, the status line - SNAP, ORTHO, tracking coordinate entry etc. Learning to float and dock toolbars. Using the ZOOM command; the value of the central mouse wheel in controlling your view of a design. Introducing the concept of layers in CAD drawings; we look at a survey drawing and an architects plan for a laboratory. The status bar. The importance of the text screen window using the DISTANCE command as an example. Saving CAD files. Different CAD file formats. The importance of understanding the underlying sequence in all IntelliCAD/AutoCAD commands. Creating CAD logos. Placing some text using different methods. An introduction to 3D visualization techniques.

Working to a Drafting Standard

Does your P&ID drawing meet the company standard. AutoCAD drawing standard tool. Using an AutoLISP program to automate checking. What blocks are used in a drawing? Counting blocks using AutoLISP.

Preliminaries

Setting up your CAD workstation. Operating systems and CAD workstations - Windows 95, 98, 2000, XP and XP Pro. Setting screen resolution. The value of using setting up and using dual monitors in your CAD workstation. Selecting the correct pointing device mice and digitizers. Creating the correct environment for CAD by configuring your CAD software. Setting the time interval for automatic backup. Installing CAD software. Protecting the unlock codes for your CAD software. Tuning and maintaining your CAD workstation. Making a suitable folder structure & filing system for CAD drawings. Starting a dialogue with your on-line CAD tutor.

Viewing Drawings

Controlling your view of a CAD drawing. The use of ZOOM, PAN, HIDE, VPOINT, REGEN and REDRAW commands. Capitalization of command options. How to get help when using an unfamiliar command - context sensitive help. Using the LIST command to measure the length of a wall (in feet and inches). Picking commands from toolbar icons - the ZOOM Extents sequence. Getting help in IntelliCAD and AutoCAD. The importance of recognizing the underlying sequence in all AutoCAD/IntelliCAD commands. The value of a proper printed manual. Using the REDRAW command. Moving between Paper Space and Model Space using the TILEMODE command. Switching spaces using tabs. The importance of the UCSICON command. Embedding raster images such as those taken with a digital camera in CAD drawings. Building a list of shortcuts for individual commands.

Precise Geometry

Experimenting with some of the more esoteric drawing commands in AutoCAD and IntelliCAD. Compound lines with the POLYLINE command, the SPLINE command, the RAY command, the ELLIPSE command, the POLYGON command, the POINT command. The ERASE command. Setting up a 400mm GRID. Building a design for a courtyard by snapping to grid points to demonstrated that drawing with precision can be a simple process. The COPY command - using the multiple option. Using some simple editing commands - ERASE, TRIM, EXTEND. Using CAD to create a very simple design - we will take a design for a rose garden as a simple example. The CIRCLE and OFFSET commands. Using the entity snap functions - calling the Endpoint, Centre, PERpendicular, Quadrant options from the command line. The value of setting up and using a template drawing. Using the DISTANCE command. The RECTANGLE command. The ROTATE command. The DTEXT command with a hand lettered font.

Creating a title block sheet drawing using Cartesian coordinates. We emphasize the importance of working to a defined drafting standard using AS1100 - Australian Standard 1100 for technical drafting - as an example. Setting LIMITS, using the SNAP and GRID commands. Creating a block library and saving drawings sheets to it.

Using Blocks

An understanding of the importance of blocks in the CAD environment is essential. Here we show creating and inserting a logo and schedule in a drawing. Using block library symbols, inserting blocks into a drawing sheet. P&ID symbols. Using object/entity snaps.

A new P&ID drawing

Creating a P&ID drawing from scratch, presenting the drawing in paper space.

Using layers & controlling colour

Using the LAYER command. Creating new layers, assigning layer colours and linetypes. Accurate geometry by length, angle, OFFSET, FILLET and TRIM. Placing entities on layers, inserting a north indicator, controlling colour BYLAYER and by colour entity. Blocks, layers and colour.

Text

Placing text in CAD drawings. Using various drawing aids to align text. Using the STYLE command to create new text styles. Style naming conventions and the use of fonts. Applying the DTEXT, TEXT and MTEXT commands. Controlling text justification, text height, inserting text in title blocks, single line text, paragraph text, using grid and snap.

Plotting

The PLOT and PRINT commands are used to get your drawings out to paper. We show how to inserting a drawing sheet and scale it up around your design by a known scale factor. The control of pen weights in the plotted drawings is discussed and a system which mimics using the Rotring system is proposed. We set screen colours and match to pen thickness, adjusting pens and line weights. The value of reviewing plots, plot configuration parameter files and the value of using paper space vs. model space is discussed.

Plotting 2

Another more detailed look at plotting.

Copy Across Drawings

Great gains in productivity if you understand the principles involved here.

Attributes

Storing non graphic information insides block symbols. How to create, edit and use attributes.

Housekeeping - qualty check drawings

A small module on the steps to take towards keeping your drawings 'clean' and robust. We check out a drawing of an automated gate assembly which had been causing a user some difficulties.

Extracting Attribute Information

Extracting attribute information from blocks contained within drawings. Passing information to Excel spreadsheets and MS Access databases.

Downloads

A link to the downloads page for sample files this course (should you need it).

Custom menus

Creating, editing and using custom menus to speed the placement of P&ID symbols.

AutoLISP

Understanding the programming language which is available in the AutoCAD and IntelliCAD environment.

IntelliCAD

Background information on IntelliCAD.