The ongoing success of Valor MSS Process Preparation module at Roj is clearly driven by the integrated use of the Valor Part Library (VPL), Auto Generation (AG) of parts data for the machine library, and the Virtual Sticky Tape (VST) application to check and update correct rotation and position of all component placements offline.
“At Roj we are constantly trying to find solutions to improve the quality of our operations, both in engineering and on the shop floor. Valor’s software is helping us become much more productive and generate fewer errors.”
The manufacturing team at Roj is quality driven. This is due to continuous management objectives to improve the quality of each NPI (new product introduction) as well as each continuing production order. Quality does not only mean fewer defects and reduced waste during production, but also achieving their engineering and production schedules. One critical obstacle to quality in this SMT factory was frequent stop times experienced during the NPI cycle, due to missing or inaccurate data.
It was not uncommon for NPI production pilots to experience stop times adding up to 2 full days. These delays were invariably the result of engineers needing to make multiple corrections to part data in multiple machine libraries using SiPlace Pro, as well as edits to the pick & place programs to adjust offsets of asymmetrical components and the rotation values of polarized components.
The time savings forecasted at ROJ, when the introduction of Valor MSS will be completed, place the ROI at 36 months with an average of 20 NPI projects per year.
Before critical process documentation is transferred from Engineering to Production, including the SMT programs, machine set-up sheets and complete machine library data, Valor MSS ensures that everything is prepared to run correctly the first time.
The first use of VPL at Roj is to visualize accurate component shapes based upon the specified vendor and vendor part number as called out in the Manufacturing BOM (Bill of Material) and AVL (Approved Vendor List). Valor MSS retrieves these geometrically accurate shapes via an online service automatically by linking with the BOM.
Even if there are multiple vendors listed for the same part, Valor MSS shows each vendor shape in a graphical overlay to achieve two objectives: 1) determine if there is in fact a variation between shapes from different vendors for the same internal part number, which violates a user defined tolerance, and 2) graphically reveal the “as built” placement of the selected vendor part number onto the specified reference designator location in the CAD design.
Using these tools Roj is verifying their own internal parts database, including part height, and insuring that the correct part shape is being used in production to “fit” properly on the designated pads. (see figure 1)
Roj is also taking advantage of the accurate component shape geometries imported from the VPL by using Valor MSS Auto- Generation module to automatically create SMT part data for their SiPlace machines. A generic high level vShape is created for all components on the board which are missing from the corresponding machines libraries in the line selected for production. This is done for every machine in the line which is capable of placing the component. Using a fine tuned rule set for each machine, the software then auto-generates the complete machine library parts data (mShape) off-line. The AG process makes it possible to run new products very quickly since missing library data is created automatically. This capability also makes it possible for Roj to quickly move a product from one line to another, even if the new line has zero library data for the new board. The production flexibility is an additional way to reduce costs by improving asset utilization. (see figure 2).
Before Valor MSS, Roj would typically spend 15-20 minutes for EVERY new part shape by creating the new shapes with SiPlace Pro. It is very common for each NPI to have at least 15 new shapes. Therefore 3-4 hours of engineering time per NPI is saved using Auto-Generation, based on creating missing shapes alone.
VIRTUAL STICKY TAPE
Roj is also saving time by eliminating the need to run a sticky board as a first article to validate all component locations and rotations. Many SMT factories have adopted the sticky board process as a standard procedure so they do not run the risk of running production volumes with bad component rotations. The problem is the line time that is required to run the sticky board, inspect the results, edit the programs and then repeat to validate the corrections. Roj is achieving higher quality with no stop time by using vPlan’s Virtual Sticky Tape (VST) capability.
With Valor MSS, all component rotations are neutralized at the CAD import level to a known standard value for a zero rotation. Then software applies the correct rotation offset based on the component shape, polarity and pad locations. The resulting SMT machine programs have very few rotation issues. To insure that rotations in new programs are correct, VST virtually mounts each part and gives Roj process engineers a detail graphical view of each part as if it were place on the board. This is done by overlaying the “placed” part shapes, according to programming instructions, onto the CAD design with the silk screen displayed. Now any bad rotations are clearly seen and corrected, BEFORE the board is built on the line. Any needed corrections are performed automatically and new offsets are written to the central part library. The SMT program is also updated automatically so that production can run correctly the first time without stopping. All asymmetrical parts such as D-PAKS, are also displayed and offsets are adjusted in similar routine.
SUMMARY of BENEFITS
Valor MSS Process Preparation module is providing the technology needed for Roj to accomplish their goals to improve quality and to reduce the time investment to complete each NPI.
1. Reduce errors due to inaccurate part data
The VPL helps to flush out errors in CAD shapes and in the master part library and to confirm hard to find data points like component height. The AVL is also improved by eliminating errors or vendors which create unacceptable geometric variations in the component’s shapes. A lot of time is also saved in production by eliminating part-to-pad mismatches before they can occur on the shop floor.
2. Reduce stop time due to missing part data
NPIs always bring in new part shapes which do not exist within the machine libraries. Using the Auto-Generation capability these shapes are created instantly and with greater accuracy. This save large blocks of engineering time, creates fewer placement problems and stops “process tweaking” and the resulting library pollution from temporary “fixes” and bad part shapes.
3. Improve product quality with more accurate placement
Process yields and long term product reliability are both improved when component placement is optimized. The precise component shape geometries in the VPL ensure that machine shapes are accurate, and the VST process confirms that each placement centroid and rotation value are correct in “as built” offline simulation.
4. Reduce line stops due to rotation or position errors
Program generation with VST also ensures that the NPI board runs correctly the first time.
“Valor MSS is helping our engineering team work faster and to transfer NPI documentation to production with higher quality. We are very pleased with our decision to choose Valor as our software partner. ”
Roj is the electronics manufacturing arm of IRO Group. The IRO Group is a world leading producer of yarn feeding equipment to the textile industry. With annual sales in excess of 100 million euro, the IRO Group today provides over 60% of the global production of yarn feeders in the world. Roj is the OEM which designs and builds the electronics control systems for these industrial yarn feeders.