This document discusses data exchange standards used for transferring design data between CAD and CAM systems like IGES and DXF. It notes that these standards only transfer geometric information and not other important data. The document then introduces STEP-NC as a new standard that can overcome the limitations of previous standards. STEP-NC uses a feature-based and task-oriented approach to integrate CAD, CAM and CNC data throughout the product lifecycle. It allows bi-directional information flow and more intelligent CNC programming compared to prior G-code standards. The document concludes that STEP-NC can reshape manufacturing by providing a collaborative environment for e-manufacturing.

1. By
Asheem Kumar Palo
Centurion University of Technology and Management,
INDIA
Guided By : Dr. D. Sreeramulu

2. Data Exchange standards
 In order to transfer the data between different
Systems, a neutral file is needed
 Neutral (mostly geometric) data exchange is
needed between CAD and CAM
 Most widely used data exchange formats like
IGES, DXF

3. Problems with above data exchange
standards
 The existing standards will transfer only geometric
information
 Loss of information
 These standards will not support the data
throughout the lifecycle of the product

4. CURRENT METHODOLOGY OF MAKING PARTS
ON CNC CONTROL

5. G-Code -- Machine
Instructions
“When the designed product is produced using CNC
machine tools, the machine tool controller
needs explicit instructions describing the type
and order of individual steps required to
perform a given task. We use an instruction
language called G-Code to deliver these
instructions to the machine.”

6. Current NC programming using ISO 6983
%
N05 G54
N10 G00 Z10.000
N15 G91 G0 Z200
N20 T5 D1 WW
N30 G90 M5
N35 G00 X0.000 Y-150.000
N40 G00 Z5.000
N45 M08
N50 S3183.000
N55 M03
N60 F1477.000
N65 G00 X60.000 Y-150.000
N70 G00 Z5.000
N75 G00 X60.000 Y-150.000
N80 G01 Z-0.500
...
machine-specific part
program with axis
data generated by a
postprocessor
vendor-specific
extensions of the
original standard
only primitive motion
and switch
commands
no standardized data
format for spline
processing and
sophisticated NC
technology
Courtesy WZL RWTH Aachen
STEP-NC replaces this with a
rich, integrated data format

7. Difficulties with Current
NC Programming (ISO 6983)
 The existing CNC machines work using Standard
controller
 CAD description has to go through a post-processor
 Loss of geometric information
 Programs are not interchangeable
 Changes are not possible
 No support of complex geometry (e.g. spline) i.e.
incapable of controlling five or more axis milling
 Creates large programs, difficult to handle
 One way : from CAD to shop-floor. No feedback

8. The above difficulties can
be overcome by the new
standard called
STEP - NC

9. STEP (Standard for Exchange of Product Data)
- Formally known as ISO10303
 Improving CAD data exchange
 Replacing IGES, SET and VDAFS
 More then one million CAD stations use STEP
 All major CAD systems have STEP interfaces
What Is STEP?

10. STEP APPLICATION PROTOCOLS
Important APs for integration of CAD, CAM and CNC
 AP203-Geometry
 AP214-Geometry with GD&T
 AP224-Manufacturing Features
 AP240-process planning
 AP238-STEP-NC

11. New Method Of Making Parts on
STEP-NC Controls

12. Introduction to STEP-NC
STEP-NC is the new international data input
standard for CNC systems. It is the extension of
STEP that annotates the Design information with
Manufacturing information.
It includes,
- information about the stock,
- Its manufacturing features,
- the tool requirements and
- manufacturing process sequence

13. Features of STEP-NC
It is Feature-based and Task-oriented
It is fully compliant with STEP
It supports bi-directional information flow
Provide an effective link between CAD/CAM and CNC
Enable interoperability of programs
High-level description of machining process -instead of
tool movement G01 x y
Object oriented and structured

14. A New Data Interface for NC
Programming

15. End user Benefits
GOAL: Reduce manufacturing costs
 50% of total process plan effort is reduced
 STEP-based system used to produce process plan visuals
 Projected 75% reduction in man hours spent

16. CONCLUSIONS
 With STEP-NC, all CAD, CAM and NC data
can be stored in a single database.
 Re-shaping of manufacturing is possible
with the implementation of STEP-NC .
 STEP-NC will allow CNC systems to
become more intelligent.
 Thus STEP-NC will emerge as a
collaborative agent in the present era of
e-manufacturing.

17. THANK YOU
An ASHEEM KUMAR PALO presentation
asheemkumarpl3@gmail.com