Extract DEXPI Files

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Last UpdatedJul 02, 2025
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The Gateway extracts the DEXPI objects from DEXPI files.

To configure extraction of the DEXPI files:

Click Extract from the left panel.
Select the type of Input Source from the drop-down box, that is, File System or S3.

For FileSystem as Input Source:

Define the Input Path for the location of the input files (DEXPI files), either typing directly or use the Browse DEXPI File Path to select a single file or Browse Folder Path to select a folder of files.
Select Save Settings.

For S3 as Input Source:

To configure the extractor for S3 as input source:

Define the elements in S3 Credential Details section. For more information, see Accessing an AWS S3 Bucket.
If you want to test connection to S3, select Test Connection. The result of the test is displayed in the bottom left status bar.
Select Save Settings.

Identifying DEXPI Objects from a DEXPI File

A DEXPI file contains hierarchical data that represents a digital description of a Plant model, consisting of both graphical and engineering-type elements. These engineering elements can have parameters such as Tag names, maximum pressure, and so on and graphical elements form the P&ID diagram of a Plant model. The Gateway extracts both types of elements so that the engineering elements and their attributes can be converted to an EIWM file and the graphical elements can be converted to an SVG file. These files can then be imported into AIM using the Import Controller.

Engineering elements set to become EIWM objects must have a unique identifier (tag). The Gateway uses default DEXPI parameters for these object IDs, but you can change these parameters, if needed, via mapping configuration in the Gateway’s Transformer.

File Object is a mandatory object and contains manifest data about the input file (see Manifest References). These data are derived from the Plant model (parent node) in the DEXPI file. As the Plant model does not contain a unique identifier, the Gateway assigns the input file name, as stored in the #MODEL_NAME# attribute. For example, if the input file is PID4545.xml then the output file will be PID4545_avngate.xml or PID4545_null.xml and the ID of its document object would be PID4545.

The manifest data includes metadata about the input file and attributes of the plant information node.

<PlantModel xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="ProteusPIDSchema_4.0.1.xsd">

<PlantInformation SchemaVersion="4.0.1" OriginatingSystem="AVEVAPID" Date="2019-01-23" Time="09:17:02" Is3D="no" Discipline="PID" Units="mm" >

<UnitsOfMeasure Distance="mm" Pressure="atm"/>

</PlantInformation>

</PlantModel>

This manifest data has a document or file object in the EIWM of:

<Object>
<ID>PID4545</ID>
<Context>
<ID>ContextId</ID>
</Context>
<ClassID>PID</ClassID>
<Characteristic>
<Name>Distance</Name>
<Value>mm</Value>
</Characteristic>
<Characteristic>
<Name>Pressure</Name>
<Value>atm</Value>
</Characteristic>
<Characteristic>
<Name>SchemaVersion</Name>
<Value>4.0.1</Value>
</Characteristic>
<Characteristic>
<Name>OriginatingSystem</Name>
<Value>AVEVAPID</Value>
</Characteristic>
<Characteristic>
<Name>Date</Name>
<Value>01/23/2019 12:00:00 AM</Value>
</Characteristic>
<Characteristic>
<Name>Time</Name>
<Value>01/01/0001 9:17:02 AM</Value>
</Characteristic>
<Characteristic>
<Name>Is3D</Name>
<Value>no</Value>
</Characteristic>
<Characteristic>
<Name>Units</Name>
<Value>mm</Value>
</Characteristic>
<Characteristic>
<Name>Discipline</Name>
<Value>PID</Value>
</Characteristic>
</Object>

As noted above, the ID for the document or File Object in the EIWM is derived from the input file name (without file extension) and not the value of the Drawing object attribute "Name". Although these are often the same, the convention is to use the input file name.

All other objects in the EIWM file are derived from Engineering elements that have a unique ID and are derived from the PlantItem or AnnotationItem objects defined in the DEXPI schema, as defined below by their classifications. These will have associations with the File Object (Plant model) and possibly also between each other.

Note: The Plant model always contains a Drawing object which has a mix of engineering and graphical attributes. Although it is not derived from either a PlantItem or AnnotationItem, it can be converted to an EIWM object, if for example, the "name" attribute is unique.

DEXPI Schema 4.0.1

Plant Item: ActuatingFunction, ActuatingSystem, ActuatingSystemComponent, Component, Equipment, InformationFlow, InstrumentationLoopFunction, InstrumentComponent, InstrumentConnection, InstrumentLoop, MetaData, Nozzle, PipingComponent, PipingNetworkSegment, PipingNetworkSystem, PlantArea, PlantStructureItem, ProcessInstrument, ProcessInstrumentationFunction, ProcessSignalGeneratingFunction, ProcessSignalGeneratingSystem and ProcessSignalGeneratingSystemComponent.
AnnotationItem: Symbol, SignalConnectorSymbol, ScopeBubble, PropertyBreak, PipeSlopeSymbol, PipeFlowArrow, PipeConnectorSymbol, Label and InsulationSymbol.

DEXPI Schema 3.3.3

Plant Item: Equipment, InstrumentComponent, InstrumentConnection, InstrumentLoop, JunctionBox, Nozzle, PipingComponent, PipingNetworkSegment, PipingNetworkSystem, PlantArea, ProcessInstrument, SignalLine, Terminal and TerminalStrip.
AnnotationItem: InsulationSymbol, Label, PipeConnectorSymbol, PipeFlowArrow, PropertyBreak, ScopeBubble and SignalConnectorSymbol.

The following is an example of a DEXPI Equipment Graphical Element:

</Nozzle>

</Equipment>

and the representation of the above Equipment Element in the EIWM transformed as an object is as shown below:

<Object>
<ID>XMP_58</ID>
<Context>
<ID>ContextId</ID>
</Context>
<ClassID>Column</ClassID>
<Association type="Contains">
<Object>
<ID>XMP_59</ID>
<Context>
<ID>Avngate</ID>
</Context>
<ClassID>Nozzle</ClassID>
</Object>
</Association>
<Characteristic>
<Name>ID</Name>
<Value>XMP_58</Value>
</Characteristic>
<Characteristic>
<Name>TagName</Name>
<Value>B-9004</Value>
</Characteristic>
<Characteristic>
<Name>StockNumber</Name>
<Value>VCL</Value>
</Characteristic>
<Characteristic>
<Name>ComponentClass</Name>
<Value>Column</Value>
</Characteristic>

<Characteristic>
<Name>ComponentClassURI</Name>
<Value>http://Test.org/rdl/1234</Value>
</Characteristic>
<Characteristic>
<Name>ComponentName</Name>
<Value>VCL</Value>
</Characteristic>
<Characteristic>
<Name>ComponentType</Name>
<Value>Normal</Value>
</Characteristic>
<Characteristic>
<Name>ComponentTypeSpecified</Name>
<Value>False</Value>
</Characteristic>
<Characteristic>
<Name>Status</Name>
<Value>Current</Value>
</Characteristic>
</Object>

Note: The DEXPI node names or classes are not part of the attribute information. There is no attribute that can be used to identify the node name or class in the transformation. The extractor creates one custom attribute called "ElementName" and the type of this custom attribute is "system attribute". This system attribute can be used in the transformation to identify the type of the object and derive certain behaviour for each object type. But the ElementName attribute is not included in the attributes of the EIWM Object.

Example:

From the above example, an Equipment object will be extracted with a system attribute called "ElementName" and its value is "Equipment". Transformation configuration can use this element name to assign this value to the object’s class, or the you may prefer to use another attribute value, such as ComponentClass. The Elementname can also be used to identify the type of the object and derive Object ID or remove/create associations.

Identifying Characteristics and Properties

Any node in the DEXPI file has parameters defined by "name" and "value" pairs are converted to characteristics in the EIWM. Any parameters which also have a unit will be converted to properties in the EIWM.

Characteristics in the EIWM:

<Characteristic>
<Name>TagName</Name>
<Value>B-9004</Value>
</Characteristic>

Properties in the EIWM:

<Property>
<Name>MinimumDesignPressure</Name>
<Value>4</Value>
<Units>barg</Units>
</Property>
<Property>
<Name>MaximumDesignPressure</Name>
<Value>32</Value>
<Units>barg</Units>
</Property>

Identifying Associations

The DEXPI schema defines "Association" classes that contain attributes "type" and a referenced "ItemID". These are converted to associations in the EIWM file. Any pair of parent/child nodes will also have an association created between them in the EIWM.

For example:

Association in EIWM:

<ID> PBS0D9331D91F4D4144B93903B01D5C7F4A </ID>
<Context>
<ID>ContextId</ID>
</Context>
<ClassID> PlantStructureItem </ClassID>
<Association type="is a collection including">
<Object>
<ID> PBS945900F29F424D32A292F07BB90792E2</ID>
<Context>
<ID>ContextId</ID>
</Context>
<ClassID>PlantStructureItem</ClassID>
</Object>
</Association>
</Object>

Identifying the Datasets

The DEXPI schema defines a "Genericattributes" class. Objects of this Genericattributes class contain a group of attributes, which are converted to dataset objects in the EIWM. An association to its parent (containing generic attributes) is also created. These dataset objects have a system attribute named "DataSetName" with the value of the "Set" parameter, present as an attribute at the Genericattributes node level. The dataset Object ID can be derived from any one of the attributes or "DataSetName" with the combination of parent Object ID. This can be used in the transformation to derive the dataset’s Object ID.

The equivalent Dataset Object in EIWM might be:

<Object>
<ID> DexpiAttributes </ID>
<Context>
<ID> contextId </ID>
</Context>
<ClassID>DataSet</ClassID>
<Characteristic>
<Name> FluidCodeAssignmentClass </Name>
<Value> QSb </Value>
</Characteristic>
<Characteristic>
<Name PipingClassCodeAssignmentClass </Name>
<Value> 75HB13</Value>
</Characteristic>
</Object>

Any attribute value that includes a unit of measure will be converted to property in the EIWM, using the unit type defined with the attribute value, for example,

If the Units value is not present, then the default value defined in the DEXPI input file's header will be used, if relevant. If the Units value is not present or is not a correct value, then the relevant default values for the unit types, as part of the unitOfMeasure class defined in the schema, will be used. If a suitable value is not present then a warning will be logged and the attribute will be converted to a characteristic in the EIWM, instead of a property.

Note: Deriving characteristic values or units from ValueURI or UnitsURI is not supported.

The Gateway extracts the data from the DEXPI files in the form of Engineering and Graphics data, as listed below:

Engineering Objects	Graphics 2D Objects
ID (Required)	ID (with reference to Engineering Object)
TagName (Optional)	Presentation - RGB, color, Layer, Line Type, Line Weight information - (Required)
Persistent ID (Optional)	Extent - Bounding Box Information for the object (Required)
	Position/Orientation - Position of the object with respect to provided coordinate system (Required)
	Line, Circle, Trimmed Curve
	Font, Width, Height, String, Justification, Text Angle, Slant Angle
	NumPoints, FlowIn, FlowOut
	Coordinate - Lines / Polylines with minimum two numeric points
	Connection Points: To Indicate flow and connection information for the nodes between nozzle and equipment or any connection object (Required)
	Any graphics object which are defined to represent the graphics into XML

DEXPI File Structure

DEXPI file normally contains the following elements (nodes):

Plant Model
Process Instruments
Drawing Object
Piping Network System
Shape Catalogue
Drawing Graphics

All the above nodes of the DEXPI XML file get exported, by following DEXPI Schema.

The subsequent sections describe about those DEXPI File elements.

Plant Model

This node is a parent node in the DEXPI XML file and it holds the complete plant data with respect to the drawing:

Plant Information: Plant information node contains information related to schema and drawing units. If this file is exported from any source system then, this node contains information about the originating system, module name, created or exported data time, discipline used while exporting /creating this file and so on.
PlantArea: In the P&ID content of an XMpLant file, this is just an object that may be used to represent the name and attributes of named part(area) of a plant. A Plant Area is not permitted to contain model elements but may be referenced to associated segments, Equipment and so on with a named PlantArea. A PlantArea element inherits elements and attributes from the base type PlantItem.

Child Elements:

Element Name	Cardinality
Component	0.*

Attributes:

Attribute Name	Required	Description
Name	N	A string representing the name of the area. See Character encoding.

Example:

Process Instruments

Process Instruments represent the physical instruments that are common to piping systems. These instruments inherit elements and attributes from the base type ‘Plant Item’ (see schema 3.3.3 or 4.0.1). They contain information relating to components, diameter, operator type, wall thickness and process instrument elements. The Process Instrument from the DEXPI file usually contains two kinds of data:
Engineering data - Includes name, ID, component class and possibly generic attributes.
Graphics data - Defines the position, extents, presentation information and primitives such as line, circle and so on that represent the physical process instrumentation in the P&ID diagram.
You can modify the engineering and graphics data by using mapping files. Using the transformation mappings, you can modify the engineering object data, attribute name and value, presentation, font types family and related graphics data as per requirement. For more information, refer to the mapping file from the configuration folder.
The following is an example of a Process Instrument in a DEXPI file with respect to engineering and graphics data.

<ProcessInstrument ID="ID_33" TagName="TM-804" ComponentClass="LevelTransmitter">

<Extent>

<Min X="710" Y="258" Z="0" />

<Max X="726" Y="274" Z="0" />

</Extent>

<Position>

<Location X="718" Y="266" Z="0" />

<Axis X="0" Y="0" Z="1" />

<Reference X="1" Y="0" Z="0" />

</Position>

<Circle Radius="8" … />

<Text … />

<Text … />

<NominalDiameter … />

</ProcessInstrument>

This node will process in the SVG output as Process Instrument with tag TM-804 and with a nominal diameter 40, as shown below:

Drawing Object

Drawing Object node defines the drawing border and drawing border related text entities. This node may contain another drawing border node as well.

By default, a drawing object and its properties along with the text entities are exported into SVG format. The Engineering data is included as part of the Document object in the EIWM file. The following table lists the node elements under Drawing:

Node Element	Description
Drawing Border	(Graphics data) This element stores the drawing border/outline but this is at the discretion of the export tool.
Drawing Object Information	(Graphics data) This node contains metadata about the drawing and graphical annotation for the drawing object that the file contains, such as border related text entities and geometry. It might contain multiple drawing border nodes. The Red (R), Green (G) and Blue (B) values of this element define the background color for the drawing. This is in contrast to the normal use of the Presentation element that defines foreground style information. Their values can be changed in the presentation mapping configuration.
Extent	(Graphics data) Extents define the drawing area that contains all the graphics objects. Drawing extents cannot be used as an engineering object. It defines the minimum and maximum viewbox to the DEXPI geometry contents.
GenericAttributes	(Engineering data) Defines any application specific properties relating to the Drawing.
Name	(Engineering data) Defines the identity for the drawing, this must be unique in the project.
Type	(Engineering data) Defines the fixed value of PID.
Title	(Engineering data) Defines the drawing title.

Using the Color Mapping Method:

You can modify the colors of the output SVG drawing using presentation mapping, described in Presentation Mapping.

Piping Network System

A Piping Network System contains the information for a physical piping network system in the plant. Each piping network system contains many piping network segments.

Each piping network segment specifies a collection of components with common engineering properties that define a single process flow.

The following is the representation of connection for the piping components with connectors:

</PipingNetworkSegment>

</Position>

</Node>

</Position>

</Node><Node ID="XMP_2719" Type="process">

</Position>

</Node>

</ConnectionPoints>

</PipingNetworkSystem>

Note: There is one Connection object which connects two Pipingnetworksegment objects PID_17 and PID_15, represented as an association in the EIWM between the two objects.

FromID and ToID are the piping connector / component / piping segment information and nodes are the potential flow connections between the parent object and the connection objects.

If necessary, attributes and "connected to" associations can be modified using standard transformation mapping configuration.

The following are the Piping classes in the DEXPI schema:

PipingNetworkSystem
PipingNetworkSegment
PipingComponent
PipeConnectorSymbol
PipeFlowArrow
PipeSlopeSymbol
PropertyBreak
ScopeBubble
Symbol
SignalConnectorSymbol
CrossPageConnection
Text

For more information, see the schema 3.3.3 and 4.0.1.

The following table describes some properties of Piping Network Systems and Piping Components.

Properties	Description
Piping Network System
PipingNetworkSystem ID="XMP_3"	Unique ID for each object
TagName="A-20"	Actual Tag for each object
ComponentClass="PipingSystem"	Class for each object
ComponentName	This field is not mandatory or missing for network system
Specification="A1A"	Extra attribute to fill the object details
PipingComponent
ID="XMP_2035"	Unique ID for each object
ComponentName="SPCBLNOP"	Unique name between Shape Catalogue and individual object from xml file
ComponentClass="SpectacleBlindOpen"	Component class information for the Piping Component
Specification="A3B"	Specification for the Piping Component

Extract "ConnectionPoints"

This represents connection between two objects. Connection node attributes "FromID" and "ToID" are the piping connector / component / piping segment information. In the following example, FromID(PID_17) and ToID(PID_15) are two Pipingnetworksegment objects, they are being added as association called "is connected to" to the object where the connection node is present. If necessary, attributes and "connected to" associations can be modified using the standard transformation mapping configuration.

Extract ConnectionPoints Node:

ConnectionPoints are a collection of connection nodes and each node can have a flow direction as defined by the parameters of the ConnectionPoints.

Node objects may be created as EIWM objects with an association to the ConnectionPoint's parent (for example, a Piping Component).

Each Node object contains two system attributes, that is, "ElementName", "NodeIndex" and one custom attribute called "ConnectionFlow". This will be included in the EIWM Node object attributes.

The NodeIndex will be assigned in the same order as the Node in the input file's ConnectionPoints and the "ConnectionFlow" value is derived from the FlowIn or FlowOut parameters of the ConnectionPoints. The Object ID of the node object can be derived with the combination of the parent ID and "NodeIndex".

For example:

where each value of the FlowIn or FlowOut parameter is the index of the relevant node object.

Cross Page Connector

When a piping object is connected to a component on another drawing, this will be indicated by the use of a Cross Page Connector. For example, the input drawing 905675.xml may contain the following cross page connector with respect to another drawing 905679.xml:

</PipeConnectorSymbol>

where the CrossPageConnection parameters define the name of the other drawing "905679" and a label for that connection "RV-90006", which may be the name of the component in the other drawing that it's connected to. This information can be represented in the output EIWM by a pipeconnectorsymbol object with an "is crosspage to" association to the other drawing 905679.

For example:

<Object>
<ID>XMP_155</ID>
<Context>
<ID>Avngate</ID>
</Context>
<ClassID>FlowOutPipeConnectorSymbol</ClassID>
<Association type="is crosspage to">
<Object>
<ID>905679</ID>
<Context>
<ID>Avngate</ID>
</Context>
<ClassID>P&ID</ClassID>
</Object>
</Association>
<Characteristic>
<Name>ID</Name>
<Value>XMP_155</Value>
</Characteristic>

</Object>

The creation of this "is crosspage to" association is done in the transformation configuration, for example:

</Conditions>

</TargetID>

</Association>

</Associations>

In a PipeConnectorSymbol object, the cross page connector is connected to a CrossPageConnection object and connected drawing object. The is crosspage to parameter is used in the Cross Page Connector, which creates an association between PipeConnectorSymbol and CrossPageConnection.

Shape Catalogue

Shape Catalogue defines the following information in the drawing:

Graphic information used in the drawing, such as the template definition for the graphics. It consists of a list of equipment, nozzle, piping component, and process instrumentation function.
Extent information that can be used anywhere in the drawing along with the position factor and presentation, generic attributes and so on.
The grouping of shapes to import, export and view the custom shapes. You can model complex custom shapes using your modelling software and import the shapes to your models.

Note: Standard symbols are used to represent the components in the diagrams. These symbols are not to scale and are not dimensionally accurate. The referred object consists of the actual positioning and dimensions. They are used to represent a certain type of component. These symbols are also labeled with words, letters, and numbers to further identify and specify the components that they represent. The diagrams do not represent the physical locations and proximity of each component in the Shape Catalogue, as the refereed component defines the physical location. The purpose is not to serve as an illustration of the system process.

ShapeCatalogue Name="Symbols/ Symbol Library /ShapeCatalogue"

All graphical data that is standardized by an ISO norm should be identical in all documents. The goal of the ShapeCatalogue is to outsource this graphical data to a common catalogue, to ensure unambiguous use of symbols and to support their re-usability.

For a correct reference to a symbol in the ShapeCatalogue, both elements are required to have the same ComponentName and to be of the same type (for example, Equipment, PipingComponent).

The graphic representations of symbols in the ShapeCatalogue element are stored exclusively in relative coordinates, meaning that the symbol’s coordinates relate to the position (x = 0, y = 0, z = 0).

In addition, negative values in the Extent usually imply that the symbol’s position, especially in symmetric symbols, is the point zero, and therefore, its coordinates are to be interpreted as relative.

A symbol from the ShapeCatalogue element, can be rotated or scaled by using Reference and Scale. The Reference is defined by the cosine and sine of the rotation angle.

Drawing Graphics

This node contains all the graphics that are present or defined to represent the actual Plant Model. Graphics indicates the Presentation, extent, position, list of text entities to represent the engineering information, list of generic attributes to define the intelligent information to represent the graphics as engineering element and list of other supporting graphics to represent it completely.

Presentation: Specifies the layer name, color information along with R, G and B values, line type and line weight information.
Extent: Defines the drawing extent, the minimum and maximum values of XYZ coordinates.
Position: Defines the exact location of the graphics object in the drawing. This node contains following three child nodes:
- Location: Defines the exact position of the graphics in the drawing.
- Axis: Defines the information of what axis the graphics element is respect to the drawing coordinates.
- Reference: Defines the information of rotation angle with respect to the drawing coordinates.

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