ISO 14649-13:2013

INTERNATIONAL ISO
STANDARD 14649-13
First edition
2013-03-01
Automation systems and
integration — Physical device
control — Data model for
computerized numerical
controllers —
Part 13:
Process data for wire electrical
discharge machining (wire-EDM)
Systèmes d’automatisation et intégration — Commande des
dispositifs physiques — Modèle de données pour les contrôleurs
numériques informatisés —
Partie 13: Données de procédé pour l’usinage de fils électriques (fils
EDM)
Reference number
ISO 14649-13:2013(E)
©
ISO 2013

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ISO 14649-13:2013(E)

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© ISO 2013
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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Published in Switzerland
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ISO 14649-13:2013(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Process data for wire-EDM . 2
4.1 Header and references . 2
4.2 Manufacturing features for wire-EDM . 2
4.3 Additional types and entities . 7
4.4 Machining operation for wire-EDM . 8
Annex A (informative) EXPRESS listing .15
Annex B (informative) EXPRESS-G .18
Annex C (informative) Simple wire-EDM example 1 .27
Annex D (informative) Simple wire-EDM example 2 .30
Bibliography .33
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ISO 14649-13:2013(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
The committee responsible for this document is Technical Committee ISO/TC 184, Automation systems
and integration, Subcommittee SC 1, Physical device control.
ISO 14649 consists of the following parts, under the general title Automation systems and integration —
Physical device control — Data model for computerized numerical controllers:
— Part 1: Overview and fundamental principles
— Part 10: General process data
— Part 11: Process data for milling
— Part 12: Process data for turning
— Part 13: Process data for wire electrical discharge machining (wire-EDM)
— Part 14: Process data for sink electrical discharge machining (sink-EDM)
— Part 111: Tools for milling machines
— Part 121: Tools for turning machines
— Part 201: Machine tool data for cutting processes [Technical Specification]
Gaps in numbering were intentionally left in order to allow further additions. ISO 14649-10 is the
ISO 10303 Application Reference Model (ARM) for process-independent data. ISO 10303 ARMs for
specific technologies are added after ISO 14649-10. ISO 14649 is harmonized with ISO 10303 in the
common field of Product Data over the whole life cycle. ISO 14649-1 describes the different fields of
standardization between ISO 14649, ISO 10303 and CNC manufacturers with respect to implementation
and software development.
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ISO 14649-13:2013(E)

Introduction
ISO 14649-10 describes the general process data for numerical controlled machining and includes its
schema. The subject of this schema (called machining_schema) is the definition of data types, which
are generally relevant for different technologies (e.g. milling, turning, wire-EDM). It includes the
definition of the workpiece, a feature catalogue containing features, which might be referenced by
several technologies, the general executables and the basis for an operation definition. Not included in
this schema are geometric items and presentations, which are referenced from the generic resources
of ISO 10303, and the technology-specific definitions, which are defined in separate parts of ISO 14649.
ISO 14649-10 is not a stand-alone standard. Its implementation needs at least one additional technology-
specific part (e.g. ISO 14649-11 for milling). This part of ISO 14649 describes wire Electrical Discharging
Machining (wire-EDM) and it defines technology-specific data types representing the machining process
for wire-EDM.
The main text of this part of ISO 14649 provides definitions and explanations of the data entities needed
to provide control data information to an EDM controller.
The EXPRESS forms of the entities are given again in Annex A without the explanatory text for information.
Annex B provides an alternative view of these entities, with the different figures showing graphical
representations of different elements. These figures are purely informative: a detailed explanation of
the entities in the figures is given in the corresponding text definitions in Clause 4.
Two examples of ISO 14649 files, providing illustrations of possible uses, are given in Annex C and Annex D.
In addition, the schema uses machining features similar to ISO 10303-224. The description of process
data is carried out using EXPRESS language as defined in ISO 10303-11. The encoding of the data is
carried out using ISO 10303-21.
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INTERNATIONAL STANDARD ISO 14649-13:2013(E)
Automation systems and integration — Physical device
control — Data model for computerized numerical
controllers —
Part 13:
Process data for wire electrical discharge machining (wire-
EDM)
1 Scope
This part of ISO 14649 specifies the technology-specific data element needed as process data for wire-
EDM. Together with the general process data described in ISO 14649-10, it describes the interface
between computerized numerical controller and the programming system (i.e. CAM system or shop-floor
programming system) for wire-EDM. It can be used for wire-EDM operations on this kind of machine.
The scope of this part of ISO 14649 does not include tools for any other technologies (e.g. turning,
grinding). Tools for these technologies are described in other parts of ISO 14649.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 14649-10, Industrial automation systems and integration — Physical device control — Data model for
computerized numerical controllers — Part 10: General process data
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14649-10 and the following apply.
3.1
roughing
machining operation used to cut a part
Note 1 to entry: While the aim of roughing is to remove large quantities of material in a short time, the surface
quality is usually not important.
Note 2 to entry: The roughing operation is usually followed by the finishing (3.2) operation.
3.2
finishing
machining operation whose aim is to reach the tolerance of the feature required
Note 1 to entry: The finishing operation is usually preceded by the roughing (3.1) operation and followed by the
surface finishing (3.3) operation.
3.3
surface finishing
machining operation whose aim is to reach the required surface quality
Note 1 to entry: The surface finishing operation is usually preceded by the finishing (3.3) operation.
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4 Process data for wire-EDM
4.1 Header and references
The following listing gives the header and the list of entities that are referenced within this schema.
SCHEMA wire_edm_schema;
(*
Version 5 of Feb 28, 2003
Author: Gabor Erdos
Modified by: Willy Maeder
Jacques Richard
*)
REFERENCE FROM machining_schema (*ISO 14649-10*)
(
bounded_curve,
cartesian_point,
direction,
identifier,
label,
length_measure,
machine_functions,
machining_operation,
machining_feature,
machining_tool,
material,
pressure_measure,
property_parameter,
speed_measure,
plane_angle_measure,
technology,
machining_strategy,
toolpath_list
);
4.2 Manufacturing features for wire-EDM
4.2.1 General
The wire-EDM features defined in this subclause are the features that are specific for wire-EDM
technology, and are not defined in ISO 14649-10. The base class for all wire-EDM features is the
machining_feature, defined in ISO 14649-10.
4.2.2 General_path
The most general 4-axis wire-EDM operation is a manufacturing feature described by a ruled surface, but
in many cases a curve based feature description is sufficient. The general_path feature is characterized
by the fact that the tool movements are curve driven.
The general_path feature can be specified in two ways:
a) by one curve, an optional side angle and an optional transition type;
b) defined by two synchronized curves.
ENTITY general_path
SUPERTYPE OF (ONEOF(general_single_path, general_twin_path))
SUBTYPE OF (machining_feature);
END_ENTITY;
4.2.3 General_single_path
The general_single_path (see Figure 1) is defined by a general 2D or 3D curve with a slope angle
specification and some specific parameters. The 2-axis wire-EDM operation, which is very usual, is a
particular case of general_single_path where the slope angle is equal to 0 degrees.
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ENTITY general_single_path
SUBTYPE OF (general_path);
feature_principal_boundary: bounded_curve;
slope: OPTIONAL plane_angle_measure;
transition_types: OPTIONAL EDM_transition;
END_ENTITY;
feature_principal_boundary: The outline or shape that forms the principal edge of the general_path.
When travelling along the curve base as defined by its sense, the mate-
rial lies on the left side of the curve according to the axis2_placement_3d
orientation (i.e. when projecting the curve in the local xy plane). It is the
axis2_placement_3d inherited from the machining_feature that defines
the local z-axis and the local xy plane. IF “x_+3” “” “”
IF “x_-3” “” “”
slope: Optional angle of the border of the general_path measured against the
local z-axis. Default is 0 degree. Implicitly a secondary curve bound-
ary is defined: this is done by extending a line from each point on the
principal boundary curve, at the specified angle, until it intersects the
secondary local plane at the distance depth along the negative local
z-axis. The shape of this implicit secondary boundary is also governed
by the transition_types.
transition_types: The type of transition between non-tangent segments.
a
b
1
Key
1 feature_principal_boundary
a slope
b depth
Figure 1 — General_single_path
4.2.4 General_twin_path
The general_twin_path is defined by two general 2D or 3D curves. The two curves are synchronized by
the curve parameterization. This means that the side wall is defined by connecting the points on the
principal and the secondary boundary curves corresponding to the same parameter value with a line.
The depth attribute defined in the machining_feature is not useful for this definition and is ignored.
ENTITY general_twin_path
SUBTYPE OF (general_path);
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feature_principal_boundary: bounded_curve;
feature_secondary_boundary: bounded_curve;
END_ENTITY;
feature_principal_boundary: The outline or shape that forms the principal edge of the gen-
eral_path. When travelling along the curve base as defined by its
sense, the material lies on the left side of the curve according to the
axis2_placement_3d defined in the machining_feature (see Figure 2).
IF “x_+3” “” “” IF “x_-3” “ borders>” “”
feature_secondary_boundary: The outline or shape that forms the secondary edge of the general_
path.
2
a
1
Key
1 feature_principal_boundary
2 feature_secondary_boundary
a depth
Figure 2 — General_twin_path
4.2.5 General_path_pocket
This is the abstract base class for wire-EDM pockets. Derived from this base class are closed pockets
and open pockets. The geometry of the pocket is defined with a general path. The pocket may possess
one or more bosses.
ENTITY general_path_pocket
ABSTRACT SUPERTYPE OF (ONEOF(general_path_closed_pocket, general_path_open_pocket))
SUBTYPE OF (machining_feature);
its_hole: SET [0:?] OF general_path;
END_ENTITY;
its_hole: Optional list of general_path entities which define the outline of the holes. This defines
one or more parts of the pocket which are not cut during manufacturing of the pocket.
When cutting the pocket the hole(s) is(are) cut simultaneously. IF “x_+3” “ ders>” “” IF “x_-3” “” “”
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4.2.6 General_path_closed_pocket
Derived from the class general_path_pocket, a general_path_closed_pocket (see Figure 3) is a general_
path_pocket that is surrounded by material everywhere along its circumference.
ENTITY general_path_closed_pocket
SUBTYPE OF (general_path_pocket);
feature_boundary: general_path;
END_ENTITY;
feature_boundary: The shape that describes the principal and secondary edges of the pocket. It is an
enclosed area that has completely closed profile curves. The general_path entity
specifies the volume required by a closed pocket. IF “x_+3” “” “”
IF “x_-3” “” “”
a
a depth
Figure 3 — General_path_closed_pocket
4.2.7 General_path_open_pocket
Derived from the class general_path_pocket class, a general_path_open_pocket is a general_path_
pocket which is not a general_path_closed_pocket. The wall_boundary specifies the limit of the pocket
from the open side.
ENTITY general_path_open_pocket
SUBTYPE OF (general_path_pocket);
open_boundary: general_path;
wall_boundary: OPTIONAL general_path;
END_ENTITY;
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open_boundary: The shape that describes the principal and secondary edges of the pocket. The
general_path entity specifies the volume required by the pocket. When travelling
along the curve base as defined by its sense, the material lies on the left side of the
curve according to the axis2_placement_3d defined in the machining_feature. IF
“x_+3” “” “” IF “x_-3” “” “” Tbl_no_borders>
wall_boundary: Optional general_path entity which describes the shape of the pocket from the open
side. Note that it is necessary to define this contour only if it differs from the side
wall obtained by connecting the start and end points of the open_boundary with
straight lines (see Figure 4).
1
2
Key
1 open_boundary
2 wall_boundary
Figure 4 — General_path_open_pocket
4.2.8 Ruled surfaces
The description of the shape by ruled surfaces (see Figure 5) is used when normal vectors of the surfaces
are necessary for the calculation of the wire offset, e.g. when the calculation of the offset in the two
horizontal planes is not accurate enough.
The final shape of the cut is described by a list of ruled surface. The entity region_surface_list, which
is a subtype of the entity manufacturing_feature, is used to describe the ordered and oriented list of
surfaces. The normal vector of the surface defines the direction away from the material.
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ISO 14649-13:2013(E)

1
Key
1 region_surface_list
Figure 5 — Ruled surfaces
4.3 Additional types and entities
4.3.1 General
This subclause includes some further types and entities that are used in the declaration of the machining
features described above.
4.3.2 EDM_transition
The entity EDM_transition is used in the context of the general_path class declaration. In the case when
the general_path class is defined by one curve (feature_principal_boundary) and a wall angle (slope) the
transition has to be specified in order that the shapes of the angles are correctly defined.
TYPE EDM_transition = ENUMERATION OF (constant_radius, conical, sharp);
END_TYPE;
The conical transition signifies that the secondary boundary curve is defined as the offset curve of the
principal boundary curve. The constant radius transition defines the secondary curve by keeping the
corner radius constant on the principal and secondary boundary curves (see Figure 6).
a) Feature_principal_boundary conical
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b) Feature_principal_boundary constant radius
c) Feature_principal_boundary sharp
Figure 6 — EDM_transition types
4.4 Machining operation for wire-EDM
4.4.1 General
In this subclause, all machining operations and technology-specific data needed for wire-EDM are introduced.
4.4.2 Wire_edm_machining_operation
The wire_edm_machining_operation classes define the machining process for a limited area of the
workpiece, i.e. the contents of a machining workingstep. This entity is inherited by the machining_
workingstep class defined in ISO 14649-10. This class defines additional information needed by the
wire-EDM machining. It is a subtype of entity machining_operation defined in ISO 14649-10.
ENTITY wire_edm_machining_operation
SUBTYPE OF (machining_operation);
offset_length: OPTIONAL length_measure;
approach: OPTIONAL wire_edm_approach_retract_strategy;
retract: OPTIONAL wire_edm_approach_retract_strategy;
thread_point: LIST OF [1:2] OF cartesian_point;
cut_end_point: OPTIONAL cartesian_point;
END_ENTITY;
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offset_length: Optional offset value defining the distance of the wire centre from the boundary
curve of the feature. The controller based on the required tolerance and surface
quality can determine this value. When travelling along the boundary curve of the
feature based as defined by its sense, the offset curve lies on the left side of the
curve (see Figure 7). IF “x_+3” “” “” IF “x_-3” “ Tbl_no_borders>” “”
approach: Defines the wire movement from the thread_point to the cut_start_point. If this is
not defined the wire will start from the end point of the previous machining_work-
ingstep.
retract: Defines the wire movement from the cut_end_point to the thread_point. If this is not
defined the wire will stop at the cut_end_point.
thread_point: Defines the starting point of the cutting process. This point defines the threading
hole’s position where the wire can be threaded. In the case of the four axis wire-
EDM operation the inclined threading hole can be defined by two points. The first
point is defined in the xy plane (z = 0) while the second point is defined in the xy
plane (z = -depth) of the feature coordinate system (see Figure 7).
cut_end_point: Optional point defined on the principal boundary curve that specifies the end point
of the cutting operation. If it is not defined the cut_start_point is considered as the
end point
(see Figure 6).
Figure 7 — Wire_edm_machining_operation
4.4.3 Wire_edm_machining_strategy
4.4.3.1 General
The wire_edm_machining_strategy class specifies the strategy to be used when executing the operation.
When it is specified it will modify the final offset toolpath generation method or gives a hint for an
auxiliary operation like fixation or slug removal. It is a subtype of entity machining_strategy, defined in
ISO 14649-10.
ENTITY wire_edm_machining_strategy
ABSTRACT SUPERTYPE OF (ONEOF (backmotion,cut_through,slug_removal))
SUBTYPE OF(machining_strategy);
END_ENTITY;
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4.4.3.2 Backmotion
If the backmotion strategy is specified it defines that the wire tool should move backwards on the feature
contour curve, starting from the cut_end_point towards the cut_start_point along the negative sense of
parametrization. This strategy can be applied on features having closed contour curves (see Figure 8).
ENTITY backmotion
SUBTYPE OF(wire_edm_machining_strategy);
END_ENTITY;
Figure 8 — Backmotion strategy
4.4.3.3 Cut_through
The cut_through strategy specifies that the operation will cut a slug. This strategy signifies that the slug
might have to be fixed before this operation starts in order to avoid the fall out of the slug causing a short
circuit. The wire tool should start moving from the cut_end_point towards the cut_start_point along the
positive sense of parametrization. This strategy can be applied to features having closed contour curves
(see Figure 9).
ENTITY cut_through
SUBTYPE OF(wire_edm_machining_strategy);
END_ENTITY;
Figure 9 — Cut_through strategy
4.4.3.4 Slug_removal
The slug_removal strategy defines that the operator should remove the slug. The machining_operation
having slug_removal strategy usually follows an operation having cut_through strategy. The wire should
not move during this operation. This strategy can be applied to features having closed contour curves.
It might signify to the controller that the wire should be cut before this operation and re-threaded after.
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ENTITY slug_removal
SUBTYPE OF(wire_edm_machining_strategy);
END_ENTITY;
4.4.3.5 Wire_edm_machine_functions
The entity describes the state of various functions of the machine (e.g. coolant) to be applied during the
time span of an operation. It is a subtype of entity machine_functions, defined in ISO 14649-10.
ENTITY wire_edm_machine_functions
SUBTYPE OF (machine_functions);
coolant: BOOLEAN;
coolant_pressure: OPTIONAL pressure_measure;
lower_nozzle: BOOLEAN;
upper_nozzle: BOOLEAN;
other_functions: SET [0:?] OF property_parameter;
END_ENTITY;
coolant: If true, the coolant is activated. IF “x_+3” “” “”
IF “x_-3” “” “”
coolant_pressure: Optional specification of the pressure of the coolant system. Only valid if coolant is
true.
lower_nozzle: If true, lower nozzle is activated. Only valid if coolant is true.
upper_nozzle: If true, the upper nozzle is activated. Only valid if coolant is true.
other_functions: Optional list of other functions of generic type.
4.4.3.6 Wire_edm_technology
This entity defines the technological parameters of the wire-EDM operation. It is a subtype of entity
technology defined in ISO 14649-10. Since the number of technology parameters are machine dependent
the technology will be derived from independent parameters. Most of the wire-EDM machines use an
expert system or technology tables to define the spark generator parameters from the following data:
— material of the wire (its_wire_material of wire_tool entity)
— diameter of the wire (its_diameter of wire_tool entity)
— material of the workpiece (its_material of workpiece entity)
— cutting height (its_geometry of workpiece entity)
— final surface quality (roughness)
ENTITY wire_edm_technology
SUBTYPE OF (technology);
small_corner_strategy: OPTIONAL BOOLEAN;
other_generator_parameters: OPTIONAL SET [0:?] OF property_parameter;
END_ENTITY;
small_corner_strategy : If true, the special strategy to handle the small radius corners is acti-
vated. IF “x_+3” “” “” IF “x_-3” “ Tbl_no_borders>” “”
other_generator_parameters: Set of other property parameters of the generator of generic type.
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4.4.4 Wire_edm_approach_retract_strategy
4.4.4.1 General
Base class for the approach and retract strategy. All approach and retract strategies are defined relative
to the start or end point of the cutting operation. The start point of the approach or end point of the
retract movement are defined to be the thread point of the operation.
ENTITY wire_edm_approach_retract_strategy
ABSTRACT SUPERTYPE OF (ONEOF (along_path_strategy, linear_strategy, arc_strategy));
its_technology: OPTIONAL wire_edm_technology;
technology_switch_point: OPTIONAL LIST [1:2] OF cartesian_point;
END_ENTITY;
its_technology: Optional technology setting for the approach/retract path. If it is not set
the technology specified for the main cutting is used. IF “x_+3” “ borders>” “” IF “x_-3” “” “” borders>
technology_switch_point: Specifies the point where the technology specified for the approach/retract
movement should switch to the technology of the main cut. Only valid if
its_technology is specified.
4.4.4.2 Along_path_strategy
The along path strategy (see Figure 10) specifies the movement of the wire from the thread_point (to
the thread_point) to the start point (from the end point) of the cutting operation with a list of tool paths.
This class can describe an arbitrary approach or retract strategy.
ENTITY along_path_strategy
SUBTYPE OF (wire_edm_approach_retract_strategy);
path: toolpath_list;
END_ENTITY;
path: Specifies the path of the wire IF “x_+3” “” “” ...