Archive for wireprocess

Objective Evidence Part One: Do you really know?

July 16, 2018 Application Illustrations, C&S Technologies Comments Off on Objective Evidence Part One: Do you really know?

Companies make countless decisions each and every day. Micro decisions affecting short term operations and macro decisions affecting the company’s big picture over the long term. Whether micro or macro, good business decisions are made using factual information. And those decisions are generally based on objective analysis and free of subjective influence.

In this series, we are going to uncover questions which can be used in an assessment of a quality system for terminal crimping.

Objective evidence is a term which applies to a wide range of situations and are a basis for an effective decision. The audit process irregardless of what is being audited use objective evidence.

Objective Evidence defined: “Information based on facts that can be proved through analysis, observation and other such means of research.” Source: BusinessDictionary.com.

Part one will deal with questions surrounding the validation and pre-production process. Part two will cover the production and process monitoring. Here are some questions to consider.

Material Verification.

  • Are the right materials picked and introduced into production?
    • Surprisingly, the introduction of the wrong materials into the production stream is a cause of defects and rework. Hopefully caught before leaving the facility, a major issue if caught by the customer. Is your system set up to eliminate the possibility of employee error when picking materials for production?

Applicator Set Up.

  • Has the applicator been prepared for production?
  • Was the applicator inspected after the last production run?
  • Are the tooling capable of producing crimps that meet quality specifications?

Applicator Installation.

Crimp Measurements.

  • Are you following the recipe?
    • The recipe or defined measurements for crimp validation include wire crimp height, crimp width, pull test and visual factors. Pull test alone exposes you to the potential of crimps with high electrical resistance. Wire Crimp Height is the primary method terminal suppliers specify to measure crimp quality.

Remember it is not enough to ask good questions.  Acting on the answers to those questions are critical in managing a system of people, processing equipment and process monitoring tools.

Part two will focus on questions to ask during processing.

Upstream Quality Factors: Wire

April 7, 2018 Application Illustrations, C&S Technologies Comments Off on Upstream Quality Factors: Wire

A wire termination is a very simple process: take a wire and terminal, force them together using a range of crimping tools and voila, a crimped wire.

A quality crimp is altogether different. Not so much in the crimp process, it is is somewhat the same. But ensuring the wire performs well over the life of the product and the process to assemble that wire with repeatable quality requires specialized knowledge. And application of that knowledge to the crimp process. This is very critical in electrical assembly today with the cost of failure (rejects, re-work, loss of customer confidence, liability) being so high. Which is precisely why we publish this technical blog: to arm you with the knowledge and processing tools needed.

We have covered a number of topics directly related to crimp quality. Such as Headroom, wire to crimp process sensitivity. Also Crimp Tool Setup Variability. Using tools such as Crimp Cross Section Analysis and Crimp Monitors to validate and monitor crimp quality.

In this post, we are going to move “upstream” and consider the effect of the wire itself to the crimp process. Considering the elements of the wire and the effect on process variation. Also the process (cut and strip) to prepare the wire for crimping.

Reviewing and controlling all factors in the crimp process makes for more consistent results. And a level higher sensitivity to allow for a CFM to pick up small differences in the crimp process.

It all starts with quality wire. Consistent and repeatable material is critical to consistent crimp quality. And by extension, the ability of a crimp monitor to detect other defects related to the wire to terminal crimp process. Lot by lot and supplier to supplier consistency is important. Some of the factors in process variation:

  • Wire Stranding
    • Dimensions and Material.
    • Wire Twist.
    • Strand Count.
  • Insulation dimensions and material.
  • Wire Concentricity. Concentric wire allows for closer stripping of the insulation and ultimately better strip quality. Non-Concentric wire means the strip blades must be positioned farther away from the wire stranding to ensure the wire is not contacted by the blades, causing nicks and scrapes to the strands. Plus strip quality if affected.

Non-Concentric Wire

It continues with consistent processing methods. Wire Cut and Strip methods contribute to crimp quality in a positive or negative manner. Today’s technology motorized processing machines handle wire in a precision far better than previous generation machines. But they are far from infallible. In addition no matter how precise they are, external forces can introduce process variation that can affect the crimp process. Here are primary variables in wire cut and strip processing:

  • Strip Length. Length variation can be random or consistently high or low. Random strip length variation can be affected by the back pressure from the wire source. Consistently high or low strip lengths are typically programming errors from the process setup. Strip length variation can come from the processing equipment itself but is more of a rare condition than the conditions mentioned above.
    • Strip length variation whether random or consistent directly affects crimp quality. The conditions are the same whether an operator presents the wire to a “wire stop” in the terminal applicator or a swing arm on an automatic cutter presents the wire to the applicator. A strip length that is too short presents a high insulation condition where insulation is embedded in the wire crimp. Low insulation means the insulation is partly or completely out of the insulation barrel.

Example of Normal Crimp Curve

Example of Crimp with High Insulation

  • Strip Quality. A few conditions can affect strip quality:
    • Wire Concentricity. See above.
    • Blade Type or condition. Dull blades can cause residual insulation to enter the wire crimp. Universal V blades are good for most applications. But in some cases, no matter how much the blade setup is tweaked, the strip quality is not good. This could be due to the wire type. An alternate blade profile might be a better option. Such as a radius V style which cuts around the full periphery of the insulation.
  • Dirty Wire. This condition does not show up in a visual condition or as an error condition with a crimp monitor. It can affect the electrical properties of the wire. High electrical resistance is possible where contamination is severe. Contamination can be oxidation from wire that has been stored for a long time. In addition, residual oils or chemicals used in the wire production can be present.

Awareness of processing variables is critical. Applying this knowledge is even more critical. Employee training is important and could be considered one of your last lines of defense in detecting crimp defects. Good validation and monitoring tools are invaluable to assist in process control and improvement. Especially when your production depends on automation systems with high production rates. A lot of wires can be produced that are not possible to detect fast enough by a human.

Automate your setup validation to improve production efficiency and reduce the chance of setup error from the wrong information.

Crimp Quality Solutions is your end to end support for the terminal crimp process. We have the tools in your drive to take your crimp process to the next level. Do you have Crimp Monitors installed but do not use them? You are in the CFM Cycle. Crimp Performance Optimization is our solution to reactivate the crimp monitors to monitor your crimp process. Connect with WPS.

Headroom: Understanding Crimp Sensitivity

March 9, 2018 Application Illustrations, C&S Technologies Comments Off on Headroom: Understanding Crimp Sensitivity

Last month we introduced Crimp Force Monitoring: Optimizing Crimp Performance. The CFM Cycle as described is a real situation that a number of companies find themselves in. Optimizing the crimp process can help to exit the CFM cycle.

A terminal crimp as simple as it appears, involves several inputs. Wire, terminal, crimp tooling, the crimp press and operator (bench) or automated machine are all factors which can directly affect crimp quality and ultimately the performance and longevity of the product the wiring is installed in.

Headroom analysis is a valuable indicator of Crimp Sensitivity. Headroom isolates the wire and terminal and the match between the two.

Headroom Defined.

Headroom is the difference in peak force between crimping the terminal with and without the wire. Headroom is typically expressed as a percentage. For example headroom of 85% means the wire represents 15% of the total peak force of the wire and terminal. The higher the headroom percentage, the more sensitive the crimp is for detecting small defects such as strands missing in the crimp. Conversely, the lower the percentage of headroom, the less sensitive the crimp process is.

What Can affect Headroom?

The terminal crimp size in relationship to the wire size is the main factor in overall headroom. If the majority of force is used to form the terminal only, then there is very little margin to add the force of the wire.

It is important to note that a wire of the same gauge but different strand count/strand thickness measure similar area. So headroom percentages are similar. But the strand count and individual strand thickness can affect the amount of strands a Crimp Monitor (CFM) can detect that are missing from the crimp. Here a few examples of headroom with different wire sizes and strand counts.

Crimp with Wire

Crimp without Wire

7 Strand Wire: Average Peak Force (wire and terminal) is 6.78 (kn). Average Peak Force (Terminal Only) is 3.82 (kn). Headroom is: 6.78 – 3.82/6.78 = 43.7%.

  • Each Strand represents 6.24% of the wire portion of the crimp. Using a +,- 3% CFM tolerance, this means the CFM can detect one or more strands missing.

19 Strand Wire: Average Peak Force (wire and terminal) is 10.9 (kn). Average Peak Force (Terminal Only) is 7.36 (kn). Headroom is: 10.9 – 7.36/10.9 = 32.5%.

  • Each Strand represents 1.71% of the wire portion of the crimp. Using a +,- 3% CFM tolerance, this means the CFM can detect two or more strands missing.

26 Strand Wire: Average Peak Force (wire and terminal) is 4.52 (kn). Average Peak Force (Terminal Only) is 2.70 (kn). Headroom is: 4.52 – 2.7/4.52 = 40.3%.

  • Each Strand represents 1.55% of the wire portion of the crimp. Using a +,- 3% CFM tolerance, this means the CFM can detect three or more strands missing. And randomly detect two strands.

These are three examples of headroom calculations. Each application will be different depending on the terminal crimp profile and wire.

It should be noted that the ability of a CFM to detect small variations is greatly affected by the capability of each input in the crimp process. What may appear to be a “false reading” on a CFM is actually variation observed by the CFM compared to the reference samples. For example, Press Shut Height or Crimp Force can cause variation when all other inputs are in control. So in some cases, it may not be possible to reduce the CFM tolerance to a lower percentage due to variation in one or more process inputs.

The terminal design can affect headroom. The overall crimp profile is affected by the end use of the terminal. In some cases the terminal may require a thicker base material and that can translate into more material mass being crimped. Making headroom less sensitive.

Headroom is one tool used to Optimize Crimp Performance. The CFM-Lite CFM for Bench Presses is from C&S Technologies. This is a powerful tool for not only monitoring the crimp process but helping to troubleshoot crimp applications. Headroom analysis is a part of the CFM-Lite platform.

C&S CFM-Lite

Crimp Performance Optimization is part of Crimp Quality Solutions, end to end support for the terminal crimp process. For more information on how we can support your crimp process or the CFM-Lite, Connect Your Way to WPS.

Crimp Force Monitoring: Optimizing Crimping Performance

February 21, 2018 Application Illustrations, C&S Technologies Comments Off on Crimp Force Monitoring: Optimizing Crimping Performance

It is the same story repeated in almost every company I visit.

“We have invested in crimp force monitoring (CFM) technology for our crimp process. Invested as part of a full process automation system or installed onto bench top presses. Everything started well, but we ran into trouble along the way. We were getting false readings. The monitor was signalling an error despite the fact the crimp looked fine. After some time, our operators by-passed the monitors and continued without the CFM’s.”

You have now entered the CFM Cycle.

Crimp failure might not have happened yet but it could be looming around the corner. And that corner could be close or it could be longer off. But with every non-monitored crimp performed, the higher the probability crimp failure will occur.

What are the causes?

Typically it is a lack of understanding of the crimp process itself. Also it is possible crimping is treated as an afterthought, an assumption what looks good on the outside is the same on the inside and will perform well under normal conditions for the life of the product that a wire assembly is installed into.

Let’s consider a few factors which have likely been part of the reasoning for not using CFM’s. Or de-activating them all together.

  1. Crimp Monitors do not Solve Your Crimping Problems. Click to read. Unrealistic assumptions that all crimp setups are the same, that it will be business as usual when monitors are installed. And not not using a crimp monitor as a diagnostic as well as a monitoring tool.
  2. When a crimp monitor signals an error and the crimp looks good on the outside, it is the fault of the monitor itself. This can be an incorrect assumption. Cross Section Analysis is one tool to evaluate a wire termination that is causing the monitor to signal an error.

Good Crimp

Under Compressed Crimp

Let me be crystal clear about one point. The crimp process is one of (if not the) most critical processes in a wire assembly or harness. It only takes one defective crimp to render an assembly defective. And that defect may some take time over the life of the product to affect it’s performance. Don’t take the crimp process for granted, understand the crimp process, the elements that go into it and optimize crimp performance.

Crimping Solutions provides end to end support for the terminal crimp process. Crimp Performance Optimization is our program that offers support to companies who want to activate (or re-activate) Crimp Monitors. Crimp Performance Optimization leverages our decades long experience in the crimp process to provide the needed training and knowledge in terminal crimp technology. And the deployment of our tools to evaluate problem applications to improve crimp quality and the stability of the crimp process.

We are ready to help you to Optimize Crimp Performance. Connect with us to hear more.

Understanding Crimp Tool Setup Variability

January 17, 2018 Application Illustrations, C&S Technologies Comments Off on Understanding Crimp Tool Setup Variability

In the past, set up of an applicator to crimp a terminal was a time consuming process. Applicators were often bolted into the crimp presses and a manual adjustment to the press ram was made in order to provide the proper pull test between the wire and the terminal. Companies would acquire a large quantity of crimp presses and most high volume applications were permanently fixed to a press to reduce set up time. But at a cost of facility floor space. This was also a time when run volumes of one application were larger and spanned days and often weeks. That was then.

Today we have presses and applicators designed around a universal press shut height. Press bases and ram assemblies accommodate quick change of applicators. The applicator adjust-ability is quick and the press is only adjusted to account for tool wear.

Despite the commonality of applicator setup, each setup needs to be treated as unique. This is even more important when crimp monitors are deployed and configured to detect small crimp variations. That does not mean significant extra time for setup. But extra effort to ensure the setup is done right and initial samples are validated and meet the quality specifications.

So what can vary from setup to setup? Let’s break those down.

Presses which are routinely adjusted to match the proper crimp height and pull test mean each application can vary from it’s intended crimp spec. As a general practice, the press should be returned to it’s calibrated shut height position after each job. When the press adjustment uses a graduated scale with positive adjustment points makes the change back to the calibrated position more predictable. When no positive adjustment of the shut height is available,then exact position of the shut height is not possible without re-calibration.

Micro-Adjustment of Crimp Press.

Presses have their own variation from press to press. If the applicator is installed in a different press, this is a source of variation. The way the applicator is installed in the press can affect the setup. Dynamic Press Analysis is a way to determine piece to piece variation within a press and between presses.

Applicator service and crimp tool replacement is a source of variation even when the same wire and terminal are used.

Wire of the same gauge but with different strand quantity and diameters is a source of variation. Crimp compression can affect electrical resistance and compression of the strands can vary with the stand thickness and number of strands. A wire with 19 strands will compress differently than a 41 stand wire.

Different wire gauges crimped to the same terminal. Each terminal has a range of wire it will crimp. The crimp geometry is designed to match the wire range. Generally speaking a terminal supplier will attempt to fit as many wires into one crimp size. Mainly to reduce the amount of terminals to produce and stock. A wide range of wires in one crimp section can affect headroom when using crimp monitors. Headroom is the difference between the force to crimp the wire and terminal and the terminal only. More headroom equals the ability to detect small crimp defects.

Different lots of terminals and wire. Variation can exist from lot to lot of materials.  Over the years, that lot to lot variation is smaller due to tighter process control by the supplier. But variation can exist so validation when materials (wire barrels/reels or terminal reels) change, a re-validation is recommended.

So why is this important? Consistency in setup is critical for consistent crimp quality. Especially when crimp force monitors are being used for in process monitoring. Crimp monitors can be affected by piece to piece variation from equipment wear, material matching and in process material changes. The more consistent these elements are, the more sensitive the process is for the monitor to detect smaller defects.

Conversely the less sensitive the process is, the more difficult it is to detect small defects. And the greater the risk of accepting defect parts.

Improving your current crimp process is ongoing. Reducing sources of variation gives a higher level of confidence in your ability to deliver a high level of quality assemblies to your customers.

Don’t know where to start? Crimp Quality Solutions can help.

An Appliance Recall. Breaking down the Cause of Electrical Failure.

November 23, 2017 C&S Technologies Comments Off on An Appliance Recall. Breaking down the Cause of Electrical Failure.

As I write this, a name brand manufacturer of appliances is adding to the list of recalled Dishwashers from defective power cords. The power cord can overheat, causing a serious fire hazard. The recall extends several years and affects a number of models under different brand names. I am not going to name names, a simple internet search can give you all the information on this recall. What is significant about this recall is that there were five reports of property damage which has affected over 600,000 models. A relatively small cost part over five failures has created a massive recall involving two countries (USA and Canada). Risking hundreds of thousands of lives on top of monetary cost and cost to reputation.

We are going to drill down to the cause(s) of the component failure. Also the greater implications of all manufacturers of electrical components. And how preventative measures by applying tools and quality practices can greatly reduce the risk of component failure.

What Causes a Power Cord to Overheat?

High electrical resistance at any point along the length of the cord is a typical culprit for  excessive heat. High Electrical Resistance is caused by a number of factors. In the case of a wire assembly some factors are outlined below:

  • Wire size too small for the rated current that flows through it.
  • Connector Crimp and Wire are not properly matched.
  • Poorly crimped terminals
  • Crimp Equipment.
    • Not set up correctly.
    • Worn Tooling
    • Inconsistent Crimp Press Force.
    • Crimp missing strands.

Crimped terminals are a core connection in a wire assembly and can be a source of high electrical resistance.   High resistance in crimped terminals is directly attributed to too low and in some cases too high compression of the wire strands within the crimp. There is a direct correlation between crimp compression and electrical resistance. Crimp compression cannot be determined without cross section analysis. Pull test does not provide an accurate measurement of crimp compression (and by extension: electrical resistance). In some cases, pull test can actually decline slightly before resistance peaks.

There is a direct correlation between crimp compression and electrical resistance.

Terminals that have a crimp barrel that is too large for the terminal can cause low compression. Improper crimp tooling can also contribute to inconsistent crimp quality. Worn crimp tools, improper crimp tool setup and press force that can vary from piece to piece can also lead to inconsistent crimp quality.

Wire stripping equipment can also cause inconsistencies. Worn blades or improper machine setup can cause cut strands.  Cut strands can reduce the total compressed area in the crimp which can increase resistance.

Prevention is the Cure.

The difference between this recall taking on the dimension it has and not even happening at all could be simply a few missed checks in the assembly process. We are going to get really specific and focus on the terminal crimp process. Consider the following:

  • Knowledge of the assembly process is critical. But it is not enough. Assuming wire assembly is a simple process that does not require constant monitoring can be a critical mistake.
  • Understanding each factor in assembly and their inherent variability is important. In the case of crimping a wire to a terminal, there are five basic elements to consider. Any of these factor which are not in control can affect quality.

Where do you start?

Manufacturing Machines are well maintained and capable of repeatable piece to piece consistency. Static calibration and single piece measurement does not guarantee statistical capability. Dynamic measurement provides the way to measure process capability and repeat-ability.

Tooling is replaced before quality is affected.

Manufacturer’s Specifications are a critical start to a process validation.  Suppliers spend a significant amount of resources in developing components and the associated assembly instructions and quality standards. For example, quality standards for terminals include crimp height measurements and minimum pull test standards.  Crimp Height measurements are created which are based on optimum crimp compression.  Validate using Crimp Cross Section Analysis.

Use the Right Measurement tools. For terminal crimp height, use crimp height micrometers. Other measurements can be made by blade micrometers or dial calipers. Pull test as a secondary measurement. Cross Section Analysis for more in depth analysis of the wire under compression.

Crimp Height Micrometer

Correct Materials are used. Ensure the wire is matched to the terminal based on the supplier’s specifications.

Measure when material lots change. Materials within or between lots can cause variation in the crimp process. Re-Measure to assure there no changes in materials.

When a failure occurs of this magnitude, it can be a wake up call for the companies involved. But it also can be a valuable lesson to others.  Don’t take a chance with the future of your company. Ensure your crimp process is validated and monitored prior to and during the production process. Crimp Quality Solutions provides valuable tools and knowledge for the terminal crimp process.

Components and Processing Solutions for Large Cable Wire Processing.

October 6, 2017 Application Illustrations, Carpenter Manufacturing, Etco, Judco Mfg Comments Off on Components and Processing Solutions for Large Cable Wire Processing.

Wire comes in a multitude of sizes and configurations and is used in a vast number of electrical and electronic devices and assemblies.  In recent years, efforts to reduce overall weight of a wire harness mean smaller wire gauges and thinner wire insulation are being used.   At the same time electrical demands of some products have increased the requirement for larger cable, able to handle a higher current load.  The automotive industry is a prime example of the demands to address both ranges; smaller to bring weight down for more fuel efficiency and larger for emerging applications such as electric car batteries and hybrid fuel cells.

This article will focus on processes and components used in assemblies with large cables.

Defining Large Cable Processing.
For the purposes of this article, we will discuss processing (cut, jacket strip and wire end process assembly) on wire 6 awg and larger. Also multi-conductor cables with individual insulated wires encased in an outer insulation jacket or sheath. In general, as the wire size increases, the production volume decreases.  Production volumes typically dictate whether single or multi stage processing solutions are deployed.  We will outline single and multi stage processing solutions.

Single Processing Tools

Processing tools that perform a single function.

Wire Cut

The Wezag SH Series Hand cutter series features a ratchet action and can cut wire up to 350 mm in diameter.

The Model 31 from Carpenter Mfg is a lever style wire cutter designed to cut wire and other materials.  Featuring a guillotine blade, and adjustable wire guides, the model 31 can cut material 1″ in diameter and 4″ wide.  Wire up to 0 awg can be cut and (material dependent) up to 2/0.

Wire Strip

The Carpenter 72C is a dual blade rotary wire stripper.  The 72C processes a wide range of single and multi-conductor wire.  Quick change wire guides center the wire for nick free processing.

The Carpenter 77E wire stripper is a pneumatic heavy cable wire stripper.  The large wire grippers provide high pulling power for tightly bound insulation and large cross sections.  The 77E uses fully adjustable V blades and quick change wire guides for accurate and repeatable processing.  Form blades can also be used where V blades do not provide the desired results.

The Beri.Co.Megamax is a heavy duty programmable wire stripper capable of multi-stage precision wire stripping for cable up to 25.00 mm wire diameter. The Megamax can process large OD coaxial wire. The Megamax is one of three high capacity multi-stage wire strippers available through our partner Schaefer Megomat.

Wire Crimp

UP60Wire Process Specialties supplies crimp technology for loose and reel fed contacts.  The WDT (Wezag) UP60 shown at the left is a pneumatically activated crimping press that can crimp large terminals such as battery lugs up to 180 square mm.  Interchangeable adaptors with a wide range of die sets provide maximum flexibility.

Multi-Stage Wire Processing

Process machines that perform more than one function during a single machine cycle.

Measure/Cut

The Compu-Cut 42B is a heavy duty wire and tubing cutter with a 4″ wide blade and 1″ opening.  Flat cable and tubing as well as round wire and multi-conductor cable can be processed using the 42B.  Add additional wire separators and multiple rows of material can be processed to maximize production quantities.  The cutter head is pneumatically operated and the feed unit is electrically motor driven for accurate cut lengths.

The Compu-Cut 36A is an additional option for cutting heavy duty wire. With a special guided blade holder and a standard utility knife blade, the 36A makes precision cuts on large gauge wire as well as semi ridgid tube.

Terminals and Connectors

ETCO is a supplier of terminals and connectors.  ETCO has two manufacturing facilities in the USA for processing reel fed and loose piece heavy duty terminals.  ETCO terminals are manufactured to exacting quality requirements using state of the art fabricating equipment.

 The connector at left is a top post battery terminal.  This is one of many terminal styles for heavy cable and power cords.  ETCO can also supply custom fabricated connectors to your design.

Special Processes

The Judco FLG2 processes heat shrinkable tube around large cable, battery lugs or other connector systems.  The FLG2 is energy efficient and shrinks tube fast with low cost quartz halogen bulbs and mirrors to focus light energy around the material being processed.

These are a few solutions for processing wire and cable harnesses available from Wire Process Specialties, your authority in wire processing, connectors and terminal crimp technology.  Connect Your Way to WPS to see how we can help your company reduce cost and improve the efficiency of your wire assembly processes.

The Essential Guide to Wire Processing Automation, Second Edition is now available

September 14, 2017 Uncategorized Comments Off on The Essential Guide to Wire Processing Automation, Second Edition is now available

The Essential Guide to Wire Processing Automation provides a breakdown of the basic components of an automated wire processing machine for cut, strip and wire end process single conductor stranded wire. In edition this paper provides some of the typical options for pre and post processing as well as multi-tasking processes for the ends of the wire.

The 2017 edition includes a number of revisions to the First Edition from 2015. In addition, the resources section has new supporting articles on wire processing and crimping technology.

Subscribers of the WireProcess Connection, the newsletter of the WireProcess Global Community have access to this white paper which we deliver free of charge.

Click here to subscribe now.

Crimp Quality: Scaling it to Fit.

August 2, 2017 Application Illustrations, C&S Technologies Comments Off on Crimp Quality: Scaling it to Fit.

“Quality is never an accident. It is always the result of intelligent effort” – John Ruskin

I am sure this quote from a 19th Century English Art Critic was applicable in the era it was written.  But it is no less applicable today.

“Quality is never an accident”. Nor does Quality simply happen. It takes effort to create, build and maintain an effective quality system. The stakes are higher today than any other time in history. The cost of a reject or recall can cripple a company. No company of any size is immune from the effects of a reject claim. Can you afford the risk?

“It is always the result of intelligent effort”. Yes, you must invest time and resources. People in the company from the top to the bottom need to be actively participating in efforts to create a quality system. Ask yourself these few questions:

  • What does our existing quality system look like?
  • Is it contributing to reduced internal rework costs?
  • Is it effective to reduce the risk of defective goods leaving our facility?
  • Do we have sufficient internal resources to improve our Quality System?
  • Do we need to consider outside sources to ensure we are keeping up with emerging trends in Quality Management?

Putting it into perspective, a quality system needs to fit the company’s size and structure. What is critical to large companies with big supply contracts and the associated requirements to fulfill may not be applicable to a smaller company. But even a small company should have a basic system of Quality which should be enhanced over time. Let’s get specific and drill down to the topic of Crimp Quality. Considering the pre-production validation and process monitoring, consider the essential tools for a basic Quality System:

Validation

  • Crimp Height Micrometers
  • Blade Micrometers (or Digital Calipers)
  • Pull Tester
  • A system of recording measurements

In-Process Monitoring

  • Validation Tools above
  • Crimp Force Monitors on bench and automation mounted crimp presses.
  • Visual Inspection Requirements
  • Requirements for Frequency of Measuring production

What Else?

Knowing what a good crimp is (and isn’t) is not evident with a visual external inspection. You need to look inside. Often a view of the interior of the crimp can quickly provide clues to conditions which can affect quality and contribute to increased processing costs of rework. For example:

  • Constant Crimp Force Monitor Alarms (avoid the CFM Cycle)
  • Wire assembly failures. High electrical resistance which can cause an overheard electrical connection.

For this you need to Cross Section the Crimp. This gives you a view into the material matching (wire/terminal) as well as the process tooling.

Bend Angle is a condition from the terminal crimp process. As a wire is crimped to a terminal, material is extruded outward and can cause the terminal to bend (banana shape). This condition can cause mating issues when connectors are mated together. Also, a potential of high electrical resistance in extreme cases of mating miss-alignment. An emerging measurement requirement in USCAR 21 for automotive wire harnesses.

Networking Crimp Quality.

Software and hardware networking are becoming more economical solutions to handling data. The right automated solution can reduce pre-production validation time and errors from manual data entry. Also, it removes subjectivity from validation and in-process monitoring (it looks like a good crimp therefore it is a good crimp – a big mistake in thinking). Do you Trust or Validate?

What about Equipment Maintenance?

Most companies have a maintenance program for their processing equipment. But is it effective enough? How many crimps from a set of tooling? I have calibrated our crimp press(es) but have I determined its (their) capability to produce repeatable crimp force and shut height?

Knowing comes before Doing.

Let’s face it, we are not experts in everything. Nor should we pretend to be. It is easy to start without the knowledge of what is needed. But is it effective? Industry Experts can come alongside your personnel to guide the process and provide critical advice to focus your efforts.

Scaling Crimp Quality is important in all companies who process wire assemblies. One size does not fit all. If you already have a crimp quality system (which we hope you do), what knowledge and tools do you need to make your system better. If you do not have a crimp quality system and no reported quality failures, the clock is ticking for one which could come. Don’t take the risk, obtain the knowledge of what is needed and get started with the basic tools.

Crimping Solutions could help you. Connect with us and Let’s Get Started with an assessment of your current condition.

Quality on the Plant Floor: Trust or Validate? 

July 6, 2017 Application Illustrations, C&S Technologies Comments Off on Quality on the Plant Floor: Trust or Validate? 

We live in an environment of automation. Everywhere there are new developments in systems for making our lives more convenient. Our smartphones have become “smarter” with virtual assistants that have the right answer at the right time. Casual dialog is filled with terms like “virtual reality”, “artificial intelligence” and “the internet of things”. People are more connected now than any time in human history.

As the plant floor is automated how do we mix people decisions with those made by machines? Do we continue to trust the good but perhaps biased intentions of a worker. Or do you free them from routine decisions with the assistance of machine based systems?

We will dive into this topic and specifically in the crimp validation process. What is the decision process for the wire termination your worker has in their hand before they start producing wires? That decision has far reaching implications. Here are a few points for consideration.

Good information is critical.

Quality standards are derived from the source of the material. In the case of electrical terminations the terminal supplier is your source for measurement standards. Factors such as crimp height and width for wire and insulation crimps, pull test and visual standards. Also associated tolerances.  This information should be collected for each process setup and can be stored into a server computer.

Although not a core part of this discussion, the proper tools are also critical. For Crimp Validation, use only Crimp Height Micrometers for measuring conductor crimp height and calipers or blade micrometers for conductor crimp width as well as insulation crimp height and width. Pull test as a secondary measurement of crimp secure-ness and Cross Section Analysis to verify the internal crimp shape.

A system to pass that information to the personnel on the plant floor.

Good information is useless unless it is available for proper pre-production validation. Connecting client computers at locations on the plant floor or data entry modules on the processing machines provides provides an access point to retrieve the validation standards required. Also a potential portal for entering validation data for trace-ability and analysis.

A process that removes subjectivity from the decision to start production.

The operator of inspector has a pre-production crimped wire in their hand. At this point how do you verify the wire has been measured and meets all of the established standards. Or a few measurements pass and a few do not.

Without adequate controls, subjectivity be the plant floor personnel can creep in. Perhaps the rush to get into production can pressure personnel to cut corners and accept parts which do not fully meet quality. No matter how well trained personnel are, they are the last line of defense in pre-production and opinions can affect judgement.

Locking the equipment out of production until pre-production samples pass quality test is an important move. It is important to assure your personnel that this is not personal against them. Rather it protects them from fall out in failure conditions.

A properly configured network system with modules on production equipment can perform the dual function of production validation and release of the processing equipment for production.

In-Process Changes affecting Quality

Any change during production is an opportunity to introduce variation into the process. In the case of a wire termination, changing wire (reel or barrel) and terminal (reel) can change the process. In the case of applicator tooling, when the applicator is removed for maintenance like crimp tool changes, this is also a possibility for variation.

This presents you with two options: you can continue without validation or validate when the process changes. Not validating represents a risk which is hard to quantify. Material suppliers and tooling can have varying effects. The safer option is to perform a validation to confirm the changed process matches the initial validation. Having the ability to lock out the process equipment after a material change or maintenance and forcing a validation is a good practice. This removes any subjective opinions from creeping in.

Measure, analyze and improve.

What gets measured gets improved.  Having good information as a baseline is a good first step. The next step is analysis. Considering the strengths and weaknesses. Focusing on those areas that can contribute to long (or short) term failure in a product. Then acting on the analysis. This is fundamental to any quality improvement process.

There is a great amount of information that can be pulled from validation and in process monitoring of production. The important factor is the system. You can pick a manual method or automatically collect data from production machines and other measurement sources. Choosing an automated method removes a significant amount of manual data entry not to mention the potential of transposition error.

Tying it all Together.

You likely have most of the piece in place to automate the quality process. From production equipment to the measurement tools to validate and monitor output. Having a central server with validation standards and production data is a gateway. Connecting the components together provides the pathway for good two way communication between the plant floor (people and machines) and the server with the data collection and analysis capabilities to turn raw data into useful information for analysis and quality improvement.

Crimping Solutions and our Global Technology Partnership with C&S Technologies is your source for the technology needed in an ultra competitive manufacturing environment.

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