6 Common Mistakes of BGA Rework

Ball Grid Array rework is one of the most challenging procedures performed at assembly facilities and repair depots around the world. Doing it right depends in large part on the skills and knowledge of the rework technician. That's why we say that BGA rework is mostly science, with a big slice of art thrown in!

Procedures for BGA rework are well-defined and long established, but there are six common mistakes. These mistakes can be costly leading to the following:

1. Excessive solder joint voiding
This is often due to incorrect solder paste selection or process parameters and can compromise the integrity of the attachment and require additional rework, or result in rejection if the voiding is over 25%.

2. BGA Pad damage during the BGA removal process
This is sometimes an unavoidable hazard, and it's made worse when conformal coatings and underfill are used. Repairing damaged BGA pads is a time-consuming major headache worth avoiding.

3. Incorrect BGA orientation or joint bridging.
This means additional rework thermal cycles, and the increased risk of damage with each successive application of heat.

These problems are preventable. Let's look at the 6 Most Common Mistakes in BGA Rework and how you can avoid them!

1. Inadequate Operator Training
We can't emphasize this enough! BGA rework technicians must be fully trained, their skills practiced and developed. They must understand the materials they're working with, the tools, the process steps, and the interrelationship of all factors.

They must have the skills to evaluate and 'size up' a BGA rework situation knowledgeably and skillfully before commencing rework. And they must be able to recognize the subtle, tell-tale signs indicating the process is off-track.

2. Inappropriate Equipment Selection
It's an old saying, but true, you need the right tools to do the job properly. For BGA rework, the equipment used must have the sophistication, the flexibility, and the capability to sustain a controlled, predictable and repeatable process.

This includes closed-loop thermal sensing and control, the robustness to be able to deliver heat as the process requires, and product handling capabilities for removal and replacement. Use the most capable equipment available; this is not an area to cut corners.

3. Poor Profile Development
The BGA rework profile is as important as the assembly reflow profile, and in most cases duplicates it. Without it, you won't achieve a successful and repeatable BGA rework process.

A poorly-developed thermal profile can result in damage to the assembly or BGA component requiring additional rework cycles to the same site, and damage or reflow of adjacent components. Good profiles must be carefully developed using correct thermocouple placement and analysis of the data that they provide.

4. Improper Preparation
A professional painter knows that a good, lasting paint job is 90% preparation. Similarly, before the first heat cycle is applied to a BGA rework site, there's a lot of preparation needed if the process is going to be done right.

This includes baking out moisture from the BGA device and the board assembly to prevent 'pop-corning' and other problems and removal or protection of nearby heat sensitive components to avoid damage or inadvertent reflow.

The right decisions need to be made in advance, such as whether or not to use solder paste, choosing the right solder paste stencil, and choosing the right chemistries and alloys.

There's plenty of preparation to do, and do right, before the actual rework cycle begins. This includes an accurate assessment of such things as solder ball size; device and ball co-planarity; solder mask damage and missing or contaminated pads at the PCB site.

5. Collateral Heat Damage
Reflow of adjacent component solder connections results in oxidation, de-wetting, pad and lead damage, wicking, starved joints, component damage, and other issues that can create a host of new rework problems.

The technician must be constantly aware of the effect of heat not only on the target BGA device, but also how it is affecting other components adjacent to it, on both sides of the assembly. The goal is to minimize heat migration beyond the BGA component being reworked, and this is a function of a well-developed profile and tight process control.

6. Insufficient Post-Placement Inspection
The world beneath a BGA component is a hidden mysterious place, but not from today's X-ray inspection machines. Problems such as excessive voiding and poor placement or alignment are immediately detectable with X-ray inspection.

But just like a Radar operator, an X-ray system user needs proper training to correctly interpret and understand the image that the machine is providing. The complexity of the BGA component and the different variations in the X-ray image demand it if maximum benefit is to be obtained from this significant - and indispensable - equipment investment.

Avoiding the 6 Most Common Mistakes in BGA Rework is the best way to ensure a successful, robust, and repeatable process with fewer headaches, higher yields, and reduced costs for a better bottom line.

Several members of the Circuit Technology Center team contributed to this feature story.

Backplane X-ray Analysis

This is one of those things that drive people in this business mad. A very expensive and difficult board was manufactured successfully. All the electronic and environmental testing was completed and the board went into service. Months later the board began to perform erratically in the field.

Of course the failure was "high visibility" and everyone was under the gun to find out how and why this is happening. And fix it! The customer urgently directed all possible resources to bear and after a week or so of testing found the source of this very sneaky problem.

They discovered a dual challenge: a very thick board and leads that were (on occasion) contaminated - most likely oxidized. There was only one component type involved and this component was placed at about a dozen locations per board and not every component demonstrated the problem.

What happened was, at the affected holes on the through-hole component, barrels incompletely filled with solder, which caused the solder connection with the component lead to occasionally fail after the board had been in the field working for some time.

When the boards arrived at Circuit Technology Center our challenge was to first identify the holes that were inadequately filled and fill them. At the same time the customer wanted to ensure that all pins on the problem part were reflowed to ensure they would forevermore demonstrate proper wetting.

Once this was complete, there had to be proof that the holes were filled to everyone's satisfaction. To complicate matters these boards were covered with a thick conformal coat.

The rather large board was placed, solder side up, at about a 30 degree angle to the x-ray emitter head in order to permit full view of the barrel length. Once the board was under view, each location was photographed and a marker placed on the photo noting the holes that were clearly under-filled.

Figure 1 is an example of an x-ray snapshot of a plated hole and lead with insufficient solder.

Now came the hard part. It's easy enough to talk about reflowing ground planed pins on a .150-inch thick conformal-coated board, but to actually do it? In order accomplish this task without damaging non-affected areas, the board had to be prepared by placing thermal resistant tapes and heat deflecting material on the surrounding surface areas and components to protect the unaffected components and the solder side conformal coating.

A vacuum desoldering tool was used to remove the conformal coating from the solder-side leads to permit flow and fill at those locations. The interesting thing is that this rework was going to be performed on a BGA rework machine in order to maintain the board at a steady state high temperature using the BGA rework machine's bottom heater plates to warm the whole substrate and the topside air nozzle to drive heat into the specific rework location.

In order to maintain control of this volume of heat, thermocouples were placed under the rework locations. Thermocouples were also placed to monitor the heating of sensitive devices near the rework area.

The board was slowly heated until the proper base temperature was reached then a vacuum de-soldering iron was used to suction out the existing solder ridding the barrel of any suspect material.

The final step of the soldering phase was to add solder at the target barrels using the soldering iron and wire solder. This process was repeated until all affected plated through holes were properly filled.

The board was then cleaned in a de-ionized water washer. Once again the board was x-rayed at every location.

The rework environment was hot and demanded great patience and skill from the technicians involved. It ain't always easy, but somebody's got to do it.

Several members of the Circuit Technology Center team contributed to this feature story.

Circuit Rework News: 6 Common Mistakes of BGA Rework

RELIABILITY: CONCEPTS and TRENDS

RELIABILITY: CONCEPTS and TRENDS

by Carlos Perez

While the word reliability is frequently used, unfortunately, the way it is used ignores its true context and real implication. With the various improvement techniques in asset improvement, the use of the reliability word has created a constant advertising siege.

The most known concept to define reliability is: “Probability that an asset or system operates without failing during a given period of time under some operation conditions previously established.”

Sometimes, this concept is wrongly used due to the particular use given to the word failure.

For many, failure only means shutdowns, so they construct complex mathematical formulas to calculate shutdown probability without taking into account that a failure also occurs when being inefficient, insecure and costly, having a high rejection level, or contributing to a bad image.

Other factors to be taken into account are shutdown causes that may occur for numerous reasons, so comparing apples and oranges, as the expression goes, should be avoided. An example is comparing shutdowns due to bearing lubrication with shutdowns due to errors in bearing mountings. It is not the same changing an item because it is going to fail versus changing it because it failed versus changing it because a frequency was met before it failed.

Specifying an item that failed due to wearing is not the same as another that failed due to an improper installation or one damaged by an accident.

Is It a Statistic Issue?

A common discussion is whether or not reliability is a statistic issue. Managing data has an undeniable usefulness in the company’s management and direction. It is necessary to distinguish if statistics are used to manage real data to see its behavior or to support forecasts and estimations that sometimes border on daring and irresponsible speculations.

Some authors adhere to defining mathematical postulates as an absolute truth about failures and deny the fact that numbers of analyzed failures mix effects with causes. In addition, they deny that having failure data to analyze is accepting that failures occur and with more data come more failures.

The most common misconception of reliability is that it is like the average time between failure occurrences. This statement has several connotations to consider. The first is to remember that the cipher is an average and the failure concept is associated with more shutdowns than with unconformities, such as spilling, a nonconforming product, or increased risks, which are failures too.

Datum as such, is an average cipher. There’s a big difference between probability and reality, thus generating confusion. A probable failure is a possible failure and an occurred failure is a real failure, but a calculus logarithm doesn’t necessarily assure its occurrence at a given point.

Therefore, using calculated, desired, estimated, arbitrarily fixed, imagined, recommended by manuals and even invented ciphers may carry error percentages, inaccuracies and deficiencies requiring responsible handling.


Getting back to boiler failures:

Assume that 10 failure modes are produced within 720 hours (one month).

Only two of the failure causes listed in Figure 2 produce a shutdown, generating a total of 20 shutdown hours.

According to the traditional failure concept, the calculation of MTBF for the boiler would be: MTBF =

(720 hours - 20 hours) / 2 failures = 350 hours.

If the company’s MTBF goal is 300 hours, the goal would be met.

The probability that the boiler does not fail before the MTBF goal would be calculated this way:

e-(300/350) = 42.5 percent.

Thus, analyzing numbers may only give peace of mind to some people since there are other reasons an asset may fail, such as:

Non-compliance of cleaning standards;

Inoperative protections;

Harmful situations for security and the environment;

Greater fuel consumption, which is a greater cost.If the asset does not perform all required functions as desired, it is also considered a failure.

Therefore, if the real failure concept is applied, calculations would be different:

MTBF = 720 hours - 20 hours / 10 failures = 70 hours.

Since the company’s MTBF is 300 hours, the purpose would not be met.

With the current failure concept, the probability that the boiler does not fail before the MTBF goal

would be calculated this way: Probability = e-(70/350) = 1.37 percent.Very few companies have

data on MTBF; what they really have is datum on mean time between shutdowns.

Very few companies record failure occurrence using the failure mode scope and those that do,

their information systems make the MTBF calculation difficult.

So, what’s the solution? The time being used for mathematical calculation of MTBF or failure probability would be better spent defining failure consequences and devising an action plan to mitigate those consequences.

How to Improve Reliability

Currently, the issue facing maintenance staff is not only learning what the new techniques are, but also being able to decide which ones are useful for their companies.

If properly chosen and used in an integrated manner, maintenance practices and outputs will likely improve. Likewise, costs will be optimized. If improperly chosen, more problems will be created which, in turn, will worsen existing ones.

Some companies have gone beyond statistics and have reviewed their internal practices, carrying out benchmarking with those that are outstanding. These organizations came to the conclusion that it is impossible to talk about reliability as a unique cipher. Therefore, it is necessary to use several measurements as fundamental indicators of inputs/outputs of the processes.

The need for reliability in installations is as old as humanity, but undeniably, the growing relevance of environmental issues and their security have led to the need of changing orientation of some markets and niches due to:

More complex products.

Greater pressure to reduce costs to be more competitive.

A greater number of operational functions carried out by equipment and machines.

Requirements to reduce products’ weight and volume, and maintaining and improving performance and security standards.

Requirements to increase or reduce operation duration of products to increase or reduce demand.

Greater difficulties to carry out maintenance interventions due to asset utilization increases.

Trends to use software, electronic, pneumatic, or hydraulic components having different wearing behavior in response to components failing in function of age.

Current legislation that is increasingly more demanding and less tolerant.

Greater impact of shutdowns and operational losses on sales and products.

Growing demands for quality in services and products.

New perceptions of a company’s image or commitment.

Commitments to reduce the human life loss risk.

Requests to reduce the spilling risk or affectations of the equipment on the environment.

These new demands drive the use of strategies that have been successfully applied in many companies, strengthening global performance, optimizing costs, reducing risks, improving corporate image, lowering environmental impact and consolidating business results.

Successful companies have made a concerted effort to incorporate their maintenance improvement strategies into other corporate initiatives, avoiding or preventing the syndrome of the campaign of the moment, peak of the wave, or the promotion of the month. The best indication that this effort produces satisfaction is when it turns into a durable and stable policy.

Among the most successful tools being used consistently are:

Reliability as a global concept instead of reducing costs or downtime.

Carrying out diagnoses, audits and evaluations of maintenance practices.

A development strategic plan describing and establishing a corporate vision related to reliability and asset good performance.

Extensive utilization of performance measurements with appropriate goals.

Benchmarking to identify opportunities and barriers for improvement.

Sharing knowledge and achieving consensus among areas typically separated; using teams with different functions and specialties who work together during a specific period of time to analyze problems and opportunities aimed at a common output.

Conclusion

To achieve reliability, maintenance is not the only responsible area. It requires responsible designs, consistent and trained operators, professional purchasers and stable policies. In other words, several responsible actors take part during an asset’s lifecycle.

Maintenance is considered an action; it is more of a joint responsibility than a function.

Maintenance starts with selecting equipment and follows with installation. It is supported by the right operation and good maintenance, with support provided by purchases and inventories.

Those responsible for whether assets will be reliable or not are: design; selection; manufacturing; suppliers; installation; environment; operation; maintenance; stores; and purchases.

As you can see, improving MTBF is not enough.

Carlos Mario Perez Jaramillo is a Mechanical Engineer and Information

Systems Specialist for Soporte y Cía. Mr. Perez is a specialist in asset

management and project management and has worked in

dissemination, training and application of RCM2.

www.soporteycia.com

©2015 Reliabilityweb.com

IPC - Printed Board Design, Cleaning & Coating, Testing, Process Control, Product Assurance

Feed: IPC Blog
Posted on: sexta-feira, 20 de novembro de 2015 12:58
Author: IPC
Subject: IPC Standards Committee Reports — Printed Board Design, Cleaning & Coating, Testing, Process Control, Product Assurance

IPC Standards Committee Reports These standards committee reports from the 2015 Fall Standards Committee Meetings have been compiled to help keep you up to date on IPC standards committee activities. This is the first in the series of reports Printed Board Design The 1-10c Test Coupon and Artwork Generation Task Group met to review the newly developed Users Guide for the IPC-2221B Gerber Coupon Generator that will be released for use by the industry in late 2015.  The Generator allows for the creation of Gerber files for test coupon designs found in Appendix A of IPC-2221B, Generic Standard on Printed Board Design.  The group also reviewed a demo for a modification to the Gerber Coupon Generator for a propagated “D” coupon. Cleaning and Coating The 5-31g Stencil Cleaning Task Group met to work on IPC-7526, Stencil and Misprinted Board Cleaning Handbook. Sections 1 and 2 were revised. Material compatibility, snapback, dry vs wet wipe, nano-coating stencils, and small openings were among the subjects discussed. The 5-31j Cleaning Compatibility Task Group met to discuss how to begin verification testing. They want to create acceptability levels for OEM and CM companies. Confirmation testing and test materials were discussed. Comments on document to be reviewed after the end of the year The 5-32a Ionic Conductivity Task Group discussed the status of several ongoing projects involving Ion Chromatography. This includes: method detection limit round robin testing, IC Webinar for the SMART group from Doug Pauls, Rockwell Collins, updating WP-008, extract correlation study, localized extraction, and the J-STD-001 ROSE effort. The 5-32b SIR and Electrochemical Migration Task Group met to discuss the statuses of several ongoing projects regarding SIR testing including: Round Robin study for hard wire vs test rack testing, discussion of several test methods, High Voltage SIR testing, and review of IPC-9203, B-52 Test Coupon User’s Guide. The 5-32c Bare Board Cleanliness Assessment Task Group met to finalize the decisions made regarding five Test methods. A study was initiated to support the update of IPC-5704, Cleanliness Requirements for Unpopulated Boards in hopes of adding it as a requirement in IPC-6012, Performance of Rigid Printed Boards. The 5-32e Conductive Anodic Filament (CAF) Task Group continued the revision of IPC-9691, User Guide for the IPC-TM-650, Method 2.6.25, Conductive Anodic Filament (CAF) Resistance Test (Electrochemical Migration Testing) The 5-33a Conformal Coating Task Group met to work on Revision C of IPC-CC-830, Qualification and Performance of Electrical Insulating Compounds for Printed Wiring Assemblies. DWV/MIR white paper was presented and decisions were made regarding what to include in CC-830C. The new Test Coupon, B-54, was presented. 5-33AWG also met to work on the CC-830 Handbook. Plexus presented pictures for use by the committee and Electrolube UK showed presentation on coating performance. The 5-33g Low Pressure Molding Task Group continues to address the Draft of IPC-7621, Guideline for Design, Material Selection and General Application of Encapsulation of Electronic Circuit Assembly by Low Pressure Molding with Thermoplastics. Testing The 7-11 Test Methods Subcommittee to review a proposal by Gerard O’Brien, StandS Group, for using XRF to determine phosphorous content in ENIG. There was a discussion of a Validation Process and Method Review for IPC methods. They proposed that the TAEC review all released Test Methods, new and revised. Also proposed that IPC could potentially provide validation for Test Method operators and auditing to ensure proper testing. The 7-12 Microsection Subcommittee met to continue the revision of IPC-9241, Microsectioning Guideline (formerly MS-810) and review the comments on KAVI. Feedback from the recently released TM 2.1.1F, Microsectioning, Manual Method and a proposed Microsectioning Training course were also discussed. The D-32 Thermal Stress Test Methods Subcommittee met to discuss the next steps moving forward on the revision of TM 2.6.7.2, Thermal Shock and 2.6.27, Thermal Stress. A PIN is to be drafted and discussed at the next teleconference. Process Control The 7-23 Assembly Process Effects Handbook Subcommittee met to discuss the format and content of the new IPC-9111, Troubleshooting for Printed Board Assembly Processes, before going to Final Industry Review. Product Assurance The 7-30 Product Assurance Committee reviewed the status of the projects in its scope and started planning for the meetings to be held in APEX 2016. The 7-31b IPC-A-610 Task Group reviewed comments on IPC-A-610, Acceptability for Electronic Assemblies.  The Task Group met a second day to resolve comments on criteria comment to both IPC-A-610, Acceptability for Electronic Assemblies, and IPC J-STD-001, Requirements for Soldered Electrical and Electronic Assemblies. The group also celebrated completion of the forthcoming IPC-A-610 Revision F Amendment 1. The 7-31bc Telecom Addendum Task Group met to continue discussions on the revision of the document. The Task Group plans to update the addendum using Revision F of IPC-A-610, Acceptability for Electronic Assemblies as the base document. The 7-31f Task Group responsible for IPC-A-620, Requirements and Acceptance for Cable and Wire Harness Assemblies, met to continue revision work on the document. The 7-31j Task Group met to continue revising IPC-A-630, Acceptability Standard for Manufacture, Inspection and Testing of Electronic Enclosures.  The Task Group also discussed and approved a new title for the standard that will be introduced with the revision. The 7-31k Wire Harness Design Task Group and 7-31h IPC-HDBK-620 Handbook Task Group met to celebrate the forthcoming IPC-D-620, Design and Critical Process Requirements for Cable and Wiring Harnesses, and to open discussion on IPC-HDBK-620, Handbook and Guide to Supplement IPC-A-620. The 7-31m Fiber Optic Cable Acceptability Task Group agreed to split the working draft IPC-A-640 into separate standards for design (IPC-D-640) and acceptance (IPC-A-640). Because most of the content for the design document is already on hand, the group will focus first on IPC-D-640, with plans to ballot by APEX/EXPO, and will pick up work on IPC-A-640 near that time, with a goal to publish later in 2016. The 7-32c Electrical Continuity Task Group met to review industry responses to a survey on adjacency testing for bare printed board electrical test.  Additional input on the need to specify a minimum retention period for electrical test data and clarification on when electrical testing for Class 3 product can be agreed upon between user and supplier drove the group to determine that a “B” revision to the IPC-9252, Requirements for Electrical Testing of Unpopulated Printed Boards, should be developed for a 2016 release. The 7-34 Repairability Subcommittee met to continue revising IPC-7711/21, Rework, Modification and Repair of Electronic Assemblies. Filed under: Boards, Committees, IPC, Materials, Standards, Technical Tagged: cleaning and coating, IPC standards committee reports, printed board design, process control, product assurance, testing

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Potential Processes for Automation

Step 2: Identify Potential Processes for Automation

At this point, we need to discuss the strengths and limitations of process automation with collaborative robots. In fact, you probably already have a bunch of ideas as to what processes you would like to have automated I am afraid to say that most of the tasks you thought were good candidates for automation are probably not the best choices to begin with. We need to be realistic about what the technology can do today. Some applications are easier to automate than others and as a first integration you should start small and simple. Ideal tasks for a first collaborative robot are tasks that are highly predictable and repeatable. These are easiest to automate with a collaborative robot.   Easy to automate Harder to automate Repetitive tasks in which the robot does not apply force Pick and place Dispensing Complex logic or decision making tasks Projects that require sensors Vision Force-torque sensor Parts Little part differentiation or changeovers between similar parts Part presentation: Ordered part, structured on a table, matrix or tray Parts High changeover rates for parts with divergent properties (size, shape) Deformable parts Part presentation: Moving conveyors Unstructured presentation (bins) Interacting with fixed objects, such as boxes. Integrating communications with other machines Location controlled processes: Always pick in the same place Always place in the same place Force controlled processes: Grinding, polishing, drilling, Precision assembly Processes requiring specialized or human know-how Welding Painting   Tip: To create a quick simulation, perform the task and think about whether you could do the same task without seeing or feeling the part, its weight or the force applied by the part. In other words, could you do it blind? This will give you an indication of what kind of sensors you will need.   What’s easy to automate ? For a first automation project, the options below are recommended to enure an early success. Repetitive tasks: Robots are good at repetitive tasks and endurance applications. If you have an application that repeats the same motion all day, it is a good candidate for automation by robots. One place to look for these types of applications are places where you have repetitive stress injuries in your workers, or places that have been identified as high risk for these kinds of injuries. Part presentation in pick and place: Ordered parts: A part or a series of parts that are always in the very same position during the whole process are easy to automate. The robot will basically repeat again and again the same motion without asking any questions - or getting injured. Similar parts: Parts with similar properties: dimension, weight range or physical appearance allow for easier transitions between production changeovers and will ensure that the robot can handle these parts without tool changes. Dispensing: The part is going to be placed somewhere that requires precision, so that the part will drop in the same spot each and every time. This is an easy dispensing process. Requiring more precision is tougher, but not impossible. Matrices and trays: If you have a matrix of parts (i.e. 10 x 10 parts), or if they come in trays (for example, if you’re handling small parts), you can teach the robot how to pick each part in the matrix or tray by simply programming the initial position, ending position and the number of parts in each row and column. Fixed matrices or trays are the easiest processes to automate, but in the case of a tray, you can also program the robot to remove and bring a new tray to the spot where it will pick the parts from the tray. Keep in mind that Universal Robots offers wizards (an on-screen dialog) to automate these types of picking applications. Their wizard is embedded in the robot controller logic and can be engaged very quickly.   What’s complex to automate ? For a first automation project, we don’t recommend choosing the applications below. While they can be automated, the more complex your robotic cell, the more time, energy and money you will spend on it. It’s better to start small and increase the level of automation difficulty at the same time as you increase your automation experience. Part presentation: Unstructured part presentation: If it’s hard to find a part with your hands, it will also surely be difficult for the robot. In fact, if the parts are presented in different positions and orientations each and every time, you will need a little bit more intelligence than just a robot arm. This means more programming, and possibly sensors. Widely divergent parts: Parts that are unalike in dimension, weight range, physical geometry or that are deformable often require tool changes as well between production changeovers. While this certainly can be done, it will add a greater level of complexity to your automation project and is probably not a good place to start for a first robot integration project. Conveyors: With a little more complexity, it is possible to automate conveyors too. However, you will need to figure out details such as: speed, relative position and other specifications related to time / movement / displacement. This is another case where you will need programming to make it work Sensors: If you need to integrate any type of sensor, such as vision or force torque, the level of complexity rises. You will need to plan for more integration time and a higher cost to automate the cell overall. Integration with machines: You might need the robot to interact with a machine so they can communicate with each other. This is a relatively simple process, but can be difficult if you have never worked with automation. If you can skip this step, you are one step closer to simplicity. One trick is to have the robot use the machine interface that was built for humans, such as a manual door and a start button for example. Alternatively, a simple digital I/O wired between the machine and the robot can be used. Logic: If the process is complicated in terms of logic or if it involves decision making, this will add complexity to the robot program. If you are new to robotics, try building your programming skills with simpler tasks before attacking these types of problems. Force control related tasks: If you want the robot to grind, polish, drill, weld or paint; these processes can certainly be done by robots. But processes that require a specialized or human touch are much more complex. For the robot to go from A to B is easy. Having a robot follow a trajectory while applying a specific amount of force in a specific process is more difficult, both in terms of sensor integration and programming.   In conclusion, collaborative robots are really good at pick-and-place, material handling, and material dispensing; but applications that require applying force and momentum are going to be more complex. Again starting simple and building up expertise is the approach we find has worked best. If you’d like to explore more on applications for collaborative robots, here are a series of videos that might prove useful: Collaborative Robots Case Studies   Get the PDF version for this step here.   What's next?  Here are the upcoming chapters in our 5-step practical guide: Week 3: Get the team on board with robots. Week 4: Assess your potential applications. Week 5: Get management on board with robots.  We hope you find this series useful in getting your first robotics cell in your factory. Want to discuss your challenge? Request a consultation with our robotics applications experts.

IPC - Product Compliance Requires Supply Chain Transparency

Feed: IPC Blog
Posted on: quarta-feira, 9 de março de 2016 11:29
Author: IPC
Subject: Product Compliance Requires Supply Chain Transparency

By Tord Dennis, WSP USA Changes to the RoHS, REACH, and conflict minerals regulations make the need for supply chain transparency more crucial than ever. The European Court of Justice (ECJ) ruled in 2015 that the 0.1% threshold for notifying SVHCs ( Substances of Very High Concern) in articles applies to “each of the articles incorporated as a component of a complex product” and not to the entire article. Companies that file with the SEC must annually determine and report the sources of tin, tungsten, tantalum, and gold (3TG) in their products under section 1502 of the U.S. Dodd-Frank Wall Street Reform and Consumer Protection Act. Suppliers cannot afford to claim “confidentiality” or ignorance to the material and substance make-up of the products they sell that become part of another company’s product. Leary of public backlash and/or legal action, some OEMs are taking drastic measures such as discontinuing business with suppliers who do not give them the information they need in a timely manner. Full material declaration (FMD) is quickly becoming the “gold standard” data requirement for an OEM to accurately assess the risk of restricted materials in a product. This means that suppliers must deliver the complete material and substance breakdown of their component/product in a manner that puts the least amount of impact on their core business activities and enables the OEM to collect and aggregate similar information from other suppliers. IPC has developed a family of standards dedicated to this task. The IPC-175x family of standards (e.g., IPC-1752A for material and substance declaration and IPC-1755 for conflict minerals) establishes a standard reporting format for data exchange between supply chain participants. It defines the information that most companies need to collect in order to prove compliance. It also specifies an XML-schema which enables more efficient and effective exchange of data by enterprise data systems. Automating the exchange of FMD data is made simpler with the adoption of the IPC-175x family of standards but other critical elements must be in place to achieve success. The OEM needs to build a product stewardship process that enables them to efficiently collect and analyze the FMD data from their supply chain. This means they must have executive level support and a well thought out implementation plan for enterprise software to manage this data. The OEM and the supplier must commit to being partners in this venture; “no data means no business” for all parties involved. A statement must be included in supplier contracts that require documentation pursuant to any government’s legal requirements regarding restricted materials and substances. To learn more, attend technical conference session, S03 at IPC APEX EXPO. I will present a paper titled, “Best Practices for Product Environmental Data Collection,” on Tuesday, March 15, 2016 at 2:00 pm. To learn more or register for IPC APEX EXPO, visit www.ipcapexexpo.org. Filed under: Conflict Minerals, Environment, Health and Safety, Government Relations, IPC, Legislation, Regulations, Standards Tagged: conflict minerals, European Court of Justice, full material declaration, IPC APEX EXPO, IPC-1752A, IPC-1755, IPC-175X family of standards, REACH, ROHS, SVHC

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WHAT ABOUT FINISHING WITH A COLLABORATIVE ROBOT?

Finishing applications

With manufacturing processes becoming more and more automated, operations such as finishing are among those that are considered dangerous for human workers. With the introduction of robots that can work close to people without exposing them to hazards, it is now less risky and a lot faster to use a robot for your finishing application.  WHAT IS FINISHING? Depending on your manufacturing process, finishing can use different methods. Some of the most popular applications are sanding, deburring and polishing. As your job is basically to finish a part, you probably have already mastered this method. But you still need to figure out how to do it with a robot! Here's where we can help.  WHAT ABOUT FINISHING WITH A COLLABORATIVE ROBOT? A collaborative robot or cobot for short is a general term used to describe power and force limited robots, robots that can be used without safety guarding or that have incorporated other safety features. This means the cobot can be put beside a machine or a person and set to perform a certain task without needing to be fenced off from its surrounding environment. That being said, to introduce a cobot in a finishing application and program it to deburr or sand parts is not as simple as it sounds. You will need to choose a robot and tools that can accomplish the job and that can reach a level of performance comparable to a human worker. Here are some key factors to consider if you are looking at a finishing operation using a collaborative robot.  Robot Specs Payload : The payload is the total weight the robot can carry. You need to weigh your end effector, the heaviest raw part or tool you want to carry, plus you need to account for any force that is needed in the finishing operation. This will determine your robot payload Tip 1: Remember with power tools or other kinds of tools, you must consider their relatively high mass. The robot needs to include this in its payload. Tip 2: If you are applying force on a part, you need include this in the maximum rated payload as well.    Ease of programming: Finishing usually requires irregular paths that imply curves, acceleration, speed control and other complex programming methods. You may want to start with a simple application and build your experience on this one before going into a process that requires precision force and/or precision paths. Gripper Specs Force Feedback: Finishing requires force feedback. Using a force torque sensor will allow you to have consistent force and pressure applied on the product along a given path. This means you can limit the force at a given point and/or set a force threshold that should not be breached on a given cartesian path.. Tip 1: Make sure the force torque sensor is not interfered with by external signal noise. Tip 2: There are 2 ways to have force feedback: by placing the part on a fix force torque sensor or by monitoring the force applied by the robot directly at the robot wrist. Required Workspace Safety: The robot will work alongside humans. Some people will be aware of the danger this presents, others won't. Make sure to perform a risk assessment before building your automation project. Once you're ready to go live, make sure everyone is trained on safety rules around the robot and the risks involved with using a robot. Collaborative robots can increase the safety of your applications, but there may still be risks for your workers. Tip 1: Use ISO the standard to guide your risk assessment and don't forget to consult local regulations on this subject. To learn more, download this eBook on risk assessments for collaborative robots. Tip 2: Remember, even if the robot itself is safe, if the tool or the part it carries is dangerous, then the robot cell itself may have risks for your workers. Machine Interface: Make sure to interface your robot with the machine you will be using: Conveyor belt, power tool, etc. Tip 1: This seems simple, but this is probably the most underappreciated part of the process. Make sure to reserve time and budget for this one.  There you have it, the basics of robot, gripper and workplace specifications for using a cobot in a finishing application. If you need more information on how to shop for a collaborative robot or what their key features might be, we have put together a complete eBook on this subject.   We have created a robot cheat sheet to help you choose which specifications you need to look at depending of your application. Also we have created a work sheet, which will help you to actualize your process data, so that you have this information all in one place when you go to talk with your local robot distributor.   Want to discuss your challenge? Request a consultation with our robotics applications experts.