by Laurence Claus
I loved my job, but after twenty-six years in fastener manufacturing, I found myself at a career crossroads. Auspiciously I had options; start afresh in a new field, continue in fastener manufacturing, or start something of my own. I had a lot of great technical and business management experience to draw from, having cross pollinated in the automotive, general industrial, and aerospace market segments. I had held numerous different roles including Application Engineer, Quality Director, Director of New Business Development, General Manager, and Vice President.
Therefore, in the summer 2012 I would hang out my own shingle as an independent consultant and trainer. I imagine like many individuals that start off on their own, years of honing industry relationships resulted in my earliest clients being organizations where I had already forged a connection. So it wasn’t until I had been on my own for four or five months that I would receive my first opportunity with a client whom I had never worked with before.
As it happened, this client was a small, regional VMI distributor. They had recently renewed a multi-year contract with their largest customer. As they explained what they needed, I was shocked to learn some basic details of their new contract and quickly realized why they had sought me out. Although I had always considered the automotive OEM’s insistence on yearly “productivity” reductions for multiple year contracts, as brutal, unfair, and honestly short-sighted business, I was ill-prepared for the story that I heard from my soon to be newest client. In a nutshell, in a move seemingly straight out of the automotive purchasing handbook, my client’s customer had forced a multi-year agreement with significant contract reductions for each year of the contract. The only silver lining was that their customer made a provision that any genuine cost savings they could provide through application engineering channels would be credited towards their yearly reduction obligations.
Figure 1: Parking Lot Sign Encountered on a Customer Visit
Thus, the reason they had searched me out. At that time, they had no in-house engineering or technical resources to engage in such an activity, compelling them to find that expertise outside of their organization. The engagement essentially had me travelling to their customer’s site, going from assembly station to assembly station and noting where there might be an opportunity for cost savings, either from the fastener components or improvement to the assembly practice.
Being my first opportunity to work with this client, I was notably anxious about doing a good job and finding as many opportunities for cost savings or quality improvement as possible. I joke that the week prior I chewed my fingernails down to stumps and didn’t get a wink of sleep. Although, an exaggeration, I was concerned that there wouldn’t be much to find. How wrong could I be? After all was said and done, I would estimate that there was easily several hundred thousand dollars of potential savings, and likely, much, much more.
So let me share three examples from this experience that illustrate the value of Application Engineering and then what these experiences can teach us.
Example 1: Mispairing of Nuts and Bolts:
A little background is required to explain this first example. When designers set out to engineer a bolted joint using a standard bolt and nut they have many variables to consider. One variable that rarely ever changes, however, is the preference to have the bolt fail before the nut. Although the reasoning behind this is counterintuitive to some, it’s quite simple, it is much easier to detect that that the bolt has failed than the nut. To guarantee this behavior, therefore, the nut must be designed and manufactured to be stronger than the bolt. In fact, all the current Consensus Standards are designed to achieve this by using the “nut and bolt pairing rule.” Simply stated, this principle establishes that the Proof Strength of the nut is equal to or greater than the Minimum Tensile Strength of the bolt. The Proof Strength is an established value slightly below the Elastic Limit of the fastener (load at which fastener begins to exhibit plastic deformation), while the Tensile Strength is the ultimate load the fastener can experience before it fractures.
The Consensus Standards have been developed to be true to this principle so that fasteners made to a specific Grade or Property Class should be paired with a similar Grade or Property Class of opposing fastener type. In other words, as an example, a Grade 8 bolt should be paired with a Grade 8 nut. Although it is best to pair like with like, it would also satisfy the “rule” to pair a stronger nut with a weaker bolt. For example, pairing a Grade 8 nut with a Grade 5 bolt would still suit the principle. However, it is unlikely that anyone would choose this path because higher Grade and Property Class fasteners almost always come with a premium, since they typically require higher grade materials and heat treating.
So, let’s return to my story. This was a large manufacturing site of my client’s customer producing a wide range of their commercial refrigeration products. Many of these units were quite large and used bolts in sizes from about ½” to ¾” diameter. What I discovered though was that many of these larger diameter nut and bolted joints were Grade 8 and Grade 5 bolts paired with Grade 2 nuts. (See Figures 2 and 3) This means that my client’s customer was either assembling substandard joints or they were using superfluous high strength hardware. If, in fact, they were unnecessarily using Grade 5 or Grade 8 bolts, then they were likely paying a twenty plus percent premium for these parts. If they were using low strengths nuts, they were potentially risking assembly scrap or field failures during maintenance, both of which could contribute to unnecessary scrap or warranty costs and exposure to reputational damage.
Figure 2: Example of Grade 8 Bolt (in Yellow) Paired With Grade 2 Nut (in Silver)
Figure 3: Not Odd Combination of (3) Grade 8 Bolts (in Yellow) and (1) Grade 5 Bolt (Upper Left in Silver)- All Bolt Pairings Are With Grade 2 Nuts
Example 2: Parts Too Long and Too Strong:
This example also requires a brief introduction to bolted joint principles. Although it is often counterintuitive to the lay person, for a bolt to function as intended it must be elastic like a spring. This “stretch” is a tension force known as the Preload. As this Preload begins to grow, it generates opposing forces between the contacting surfaces of the nut and bolt (or washers if they are used) which squeeze what is in-between closed. This is known as the Clamp Load. Thus, the higher the Preload, the higher the clamping forces and more tightly the joint is held together.
Figure 4: Illustrates Preload and Clamp Load
Armed with this understanding, we see that the stronger the bolt the longer it can stretch before the material it is made of begins to yield. This means that considering bolts of the same size, the higher the strength the more Preload they can achieve and, thus, generate much higher clamping loads. This is an important consideration if the application is critical and must remain tightly clamped together. In such instances, the designer should choose the highest strength, smallest diameter bolt that the design parameters can accommodate.
Returning to my story, another product line which my client’s customer manufactured at this site were the large, glass-fronted refrigerators that one finds in a convenience or grocery store. In the final step of the assembly process, these refrigerator cabinets were prepared for shipping. To accomplish this task, the assembler first raised the unit with a lift. He then walked over to a stack of wooden 2 x 4s, grabbed one off the pile, took it to a jig, and drilled two holes in it. These holes aligned with two holes drilled in a one-eighth inch sheet metal base that supported the entire unit and raised it several inches off the ground. He then took a bolt and nut, aligned the two holes, fitted a bolt through it, and finally tightened a nut against the back side of the metal flange.
As was my habit by now, I walked over and grabbed a sample of the nut and bolt. The first thing that jumped out at me was the length of the bolt. It was probably a three-eighths inch diameter hex bolt about four to four-and-a-half inches long. Now consider this, the thickness of the 2 x 4 was one-and-a-half inches and the thickness of the flange was about one-eighth inch. Considering the height of the nut with a couple of threads extending beyond the top, the length of this bolt should have been about two-and-a-quarter inches. At four to four-and-a-half inches long, the bolt was nearly twice that. This means that the bolt was about forty to fifty percent longer than necessary. As I took a closer look, I saw that this bolt was yellow. Although there is no “rule” that dictates this, it is an unofficial North American convention that Grade 5 fasteners are silver and Grade 8 are yellow. Sure enough, I looked at the head and the Grade 8 strength marking was prominently displayed. (See Figure 5) Think about this application, as the bolt is tightened and Clamp Load is generated, the soft wood material gives way, and the head begins to embed itself into the surface. In fact, because of the softness of the wood, the bolt is either unable to stretch or stretches only a small amount. Thus, a high strength bolt is unnecessary in this application. Putting it all together, my client’s customer was paying for a premium high strength bolt that was probably twice as long as it needed to be. This equated to a part costing perhaps 35%-40% more than was necessary.
Figure 5: Grade 8 Head Marking
Example 3: Combining Stainless Steel and Zinc Plated Hardware:
Perhaps the most obviously costly problem my client’s customer had was combining stainless steel and zinc fasteners together. Many of their units had cooling fans mounted on them which were covered with a protective wire grate. The connection points for the fan, grate, and side or top wall sheet metal were often comprised of a long stud or bolt that had multiple washers and nuts in the stack. I probably saw about fifty different versions of this fastening strategy. The problem was that many of these multicomponent joints were comprised of a mix of stainless steel and zinc coated steel hardware. (See Figure 6) It was clear that the intent of the Stainless-Steel hardware was to prevent corrosion in these stacks. However, it was obvious that over the years manufacturing expediency, loose purchasing practice, or unclear design intentions led to them mixing components made of these two materials. Although this could actually create some accelerated corrosion of the zinc coated parts due to galvanic interaction, let’s ignore that for the moment. The bigger problem is that the stainless hardware was likely costing them four to five times more than the zinc coated hardware. If they could get away with using some zinc coated hardware in the stack, then, in theory, because all the hardware in the stack would be equally exposed to the same service environment, it could all be zinc coated steel, thus saving a great deal of money. Of course, if stainless was truly necessary then the inclusion of the zinc coated hardware in the stack created a potential corrosion site, which could have resulted in costly warranty or field maintenance costs.
Figure 6: Joint Stack Showing Mixture of Zinc Coated Steel, Stainless Steel, and Powder Paint Coated Parts
Although these are interesting stories, and they are real, more important than the story is what they can teach distributors about value and application engineering. From the last example someone might want to argue that more money could be made by ignoring this discovery and continuing to sell the potentially unnecessary stainless steel hardware. So, why suggest a change? To answer this, one must raise another question, specifically, what does such a strategy achieve in the long run? The simple answer to that question is, most likely, a dissatisfied, disloyal customer who will flee to the next cheapest solution or vendor at the first available opportunity. In contrast, the ideal scenario is a satisfied and fiercely loyal customer that has no reason to seek out other vendors. One way for distributors to earn this loyalty is to foster a “solution provider” reputation and strongly support applications and value engineering activities. So, returning to the previous examples, what can they teach us about becoming “solution providers”?
Know and Recognize Errors in Fundamental Fastener Engineering:
Distributors should have engineers or technically minded individuals at their disposal that understand fundamental fastener engineering principles for the different products that they sell. In the previous examples, the primary fastener engineering involves bolted joint technology, but thread forming technology, rivets, plastic fasteners, roll pins, to name a few, all operate on established fundamental engineering principles. If you don’t have internal experts for each product line you sell, consider the following:
- Develop From Within Through Training: Find available training that would benefit members of your team. This might involve sending one or more team members to an external training class such as the weeklong “Certified Fastener Specialist” training conducted by the Fastener Training Institute. For more customized training or when the goal is to reach more than a couple of individuals, bringing in an on-site trainer such as NNi Training makes sense. In some instances, distributors can benefit from the relationships they have with their manufacturing vendors. Many of these suppliers are both well equipped and eager to teach their distributor customers more about their products. Finally, consider adding training sessions to sales or other similar meetings which utilize outside experts or vendors.
- Engage External Experts: When building the expertise with in-house experts is not practical, a good solution is to partner with an outside expert or trainer. The stories in this article represent an example where a distributor client of mine did just that. Lacking in-house engineering, they hired me to provide specific application engineering services they did not have. In addition to such services, over the years I have been hired on multiple occasions to provide training for distributors at their customers as well as retained as an on-call source of assistance when problems or questions arise that they don’t have the in-house knowledge to immediately answer.
- Subscribe to IFI’s Technology Connection: About ten years ago the Industrial Fasteners Institute (IFI) released its IFI Technology Connection (ITC). This is a one-of-kind web-based subscription service full of valuable technical information on fasteners. Many users claim it is indispensable to helping them navigate around often confusing fastener standards and fastener technology issues.
- Join North American Fastener Standardization Activities: Participation on the committees that generate fastener standards is open to all. In fact, it is highly encouraged. The fastener committees: ASME B18, ASTM F16, ISO TAGs, and the SAE Fastener Committee are always looking for new and engaged members to join their ranks. The cost is usually just the time invested in participating in the process and travel to the meetings, while the returns can be quite substantial. Engaged participants not only learn a tremendous amount about the subjects they are working on but establish a network of industry contacts and friends that can provide invaluable assistance in times of need.
Know What Drives Cost:
A good Application Engineer understands the manufacturing technologies required to make the parts they sell. An understanding of the manufacturing inputs will drive an understanding of why two parts, perhaps very similar in appearance and size might have very different costs. Understanding what drives the cost will foster a greater appreciation of the importance of fasteners but also equip your team to better handle the inevitable question from some customers of, “Why does it cost so much?”
Regularly Engage Your Customer in Application and Value Engineering Activities:
The examples I have shared here are from a single site visit and represent only three of maybe several dozen opportunities discovered by simply walking the assembly line. I have done this multiple times in my career and it has never failed to bear some fruit. Getting out and “walking the line” is probably the single most powerful tool and opportunity you have to impress your customer with your expertise and knowledge.
Another fantastic opportunity is to conduct some product teardowns. This may not be practical on a 7 Series BMW, but what if your customer makes chainsaws? Purchasing a couple of hundred-dollar chain saw and conducting a professional tear down study that identifies quality improving and cost savings ideas that you can share with your customer could pay significant returns. If you don’t have the ability to conduct a teardown internally, hire someone externally that can do it and provide you with a professional report. Sometimes just offering this to the customer will improve your reputation and earn you the opportunity. In fact, a customer agreeing to such an analysis will almost always supply you with the product to be studied at no charge.
Figure 7: Sample Teardown Analysis
Look Beyond Just the Fastener:
Very often salesmen and those looking at applications get tunnel vision. They get so fixated on selling that bolt or nut that they completely miss the greater opportunity that is staring right at them. At one point in my career, I was the General Manager for a start-up that focused on higher level products that incorporated one or more fasteners as a component. We ended up developing some parts that sold for $7.00 plus dollars apiece. If we had just sold the fastener, we would have had a $0.20 sale. These higher-level products were a real win-win situation. Our customer was able to purchase a single multi-component part from one vendor while it was a big win to our bottom line.
Figure 8: Example of a High Level Component, an Automotive Center Console Hinge, That Started By Looking At Just The Fasteners.
Every fastener is connecting or holding something together. Sometimes the design or process which makes that happen can be complicated and fraught with challenges. Finding a solution that solves a quality, scrap, or rework problem is hugely beneficial to a customer and likely opens up an opportunity to sell a higher margin fastener. When conducting a plant walk through, one should train themselves to ask questions about problems and look for clues to places where fasteners might be causing quality or efficiency problems.
Wrap Up:
The truly proactive distributor will embrace the idea of value selling. To effectively support this, however, they must have internal or external resources that can provide application engineering and technical services for their customers. Companies that really engage in such activities benefit from an improved reputation and higher margins. It simply makes good business sense!
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