After reading Why Rivet Nuts?, you may come away with, well that’s good, but what’s a rivet nut stud?
Rivet nut studs are simply rivet nuts with an already outward protruding stud installed in the rivet nut. Instead of threading the bolt into the rivet nut, you thread your attachment on to the bolt and you would attach a nut to tighten down the attachment.
Sherex Rivet Nut Studs
They work the same way as a blind rivet nut, are installed in a similar way, and already have the stud installed. This saves installers the step of putting in the through bolt. Also, when putting an assembly together, it can be beneficial to have something that gets hung on the stud before getting tightened down. This gives the operator something to take the weight off the component before installing the nut over the stud.
Like most blind rivet nuts, rivet nut studs are great replacements for weld nuts when you need a blindly installed, outward-protruding stud for your joint. They are also only needed to be installed in one side of the work piece, where access to the backside is not possible.
Rivet nut studs can come in a variety of sizes and shapes. Round body, hex body, wedge head, knurls – anything a typical rivet nut can be made into and rivet nut stud can. Rivet nut studs are very customizable. Another thing to consider is the stud. How much thread or stud length will you need for the application? Rivet nut studs can be made to a specific length for the application.
The performance of rivet nut studs vs. a typical rivet nut is very similar, although harder material like steel might yield better performance results than softer material. In general, the performance of spin-out or pull-through of a rivet nut stud compared to a typical rivet nut is negligible if all things are equal.
Rivet Nut Stud Application Use
There are a number of different applications a rivet nut could be used for:
Wire harnessing on a Truck Frame
Any applications where a rivet nut stud will be used as a hanging point on a centering pin
Locating or guide pin
Can replace any weld nut application
Automotive applications, like spoiler installations, installed into castings, roof racks
Heavy Truck applications
Rivet Nut Stud Application on Automotive Casting
Rivet nut studs are typically more expensive than a rivet nuts, but remember, the cost of the stud or bolt is also considered into the higher price. When you factor a rivet nut plus a bolt/stud, it’s roughly the same amount per part ($rivet nut stud = $rivet nut + $stud/bolt). Another thing to consider is the potential in time saving, or even ease of assembly for assemblers and installers. Rivet nut studs could very well be a more productive fastener depending on the application, saving money by being able to assemble more products faster.
Rivet nut studs are a great option and should be considered any time you have an application that needs a rivet nut and weigh out the options if it makes sense to use one. If you’d like to speak to one of Sherex’s application engineers to see if an application is worthy of a rivet nut stud, contact us!
There are dozens of different styles of rivet nuts manufacturers can choose from when deciding on a fastening solution to help improve their assembly. While the material, coating, size, body style are all important, how the rivet nut performs under strenuous conditions is often times what matters the most.
Performance testing of rivet nuts is extremely important. It helps validate how the rivet nut will perform under an array of conditions to give manufactures and assemblers assurance that under that same kind of stress in their own design application, their joint will be able to hold up to any expected loading condition.
Here are some of the ways Sherex conducts rivet nut performance testing.
Pull-out failure occurs when threads are pulled from the rivet nut (ultimate thread strength), or when the base material is distorted and the rivet nut (either partially or entirely) pulls through the base material. Sometimes this happens with the hole size is too big for the rivet nut or when the force applied to the joint is higher than anticipated, causing the rivet nut to pull right through the hole.
Using a tensile machine to pull the rivet nut through the hole
This is tested by assembling our joint into a tensile machine. Tensile load on the joint is increased until the integrity of the crimp fails, whether it be due to material deformation or due to severing of the crimping bubble from the flange of the rivet nut.
Spin-out is the amount of torque required to make a rivet nut spin in the hole it was installed in. This happens when the bolt cross-threads into the rivet nut, causing it to spin. It can also occur when excessive corrosion causes the bolt to bind in the nut.
What it will take for the rivet nut to spin in the hole?
This is tested by assembling a test bolt into the shank end of the rivet nut. Torque is increased until the integrity of the crimp fails and the rivet nut starts to spin in the material. Failure torque recorded is the maximum torque reached before the rivet nut starts to spin.
This is the torque required to strip threads out of the rivet nut. This method of testing sandwiches the head of the rivet nut between the non-rotational mating part and parent or base panel.
Spin-out is not a factor because tightening the bolt on the non-rotating part holds the rivet nut in place and prevents it from spinning.
Torque the bolt on the flange side of the rivet nut until the bolt, rivet nut, or base material is compromised
This is tested by assembling a test bolt into the flange side of the rivet nut, with the flange supported entirely by a hardened test plate. Torque is increased until the integrity of the joint fails, whether it be due to the bolt snapping inside the rivet nut or due to the threads of the rivet nut stripping. Failure torque recorded is the maximum torque reached before thread failure occurs.
Assembly Torque / Clamp Load
Sherex gives recommendations for the assembly torque to achieve recommended clamp load in our catalog to give the recommended torque for assembling a rivet nut joint using any Sherex-manufactured rivet nut. Testing is for this is important, because different joint configurations will produce different clamp load levels.
Assembly torque is calculated as a ratio of proof load, which designates thread strength per SAE J995 for unified (UNC/UNF) internal thread sizes and ISO 898-2 for metric sizes. This is our recommendation for Sherex-manufactured parts meant to meet Grade 5/Class 8 thread strength specifications. All torques designated represent recommendations for assembly from the flange side with the flange entirely supported.
All failure loads, torques, and assembly recommendations are heavily application-dependent, and any recommendations found in the catalog or results from different applications should only be used as a reference.
For any questions on testing or any parts that require a higher grade or property class designation, please contact us!
The Sherex Fastener Fix blog is supposed to be an unbiased, informative, technical and thoughtful conversation on all things fasteners. But once in a while we have to toot our own horn.
Sherex’s patented RIV-FLOAT® rivet nut is truly great. It allows for greater ease of assembly because fastening can occur when the through bolt is off-center.
How does this happen? There’s a .02-inch radial floating nut inside the rivet nut, which allows the bolt going through the rivet nut to be a slightly off-center while pulling the attachments together. Think of when you’re assembling a piece of furniture and you’re trying to get the final attachment holes to line up exactly for your bolt or screw. It can be a pain! With a RIV-FLOAT installed in base attachment, there can be a little play while joining the attachments together with a bolt or screw. And since RIV-FLOAT is a rivet nut, there is no need to attach a nut to the backside.
RIV-FLOAT development started in 2007. An aerospace customer had an application that required floating threads. The concept was worked on by engineering, and from there it went from drawings to life and eventually a patent.
“The idea came from a customer specific request,” Sherex president Adam Pratt recalled, “but we thought the idea had promise for other markets so we developed the product.”
Other markets include automotive, construction and agriculture equipment, and general industry applications. Applications in these industries are wide ranging. RIV-FLOAT has been used for enclosures for mounting large door panels and in difficult fastening locations where the drive angle can’t get square to the base material.
“RIV-FLOAT can improve ergonomics and improve safety,” Pratt said. “RIV-FLOAT gives customers that adjustment they need to easily assemble these applications.”
When it comes to performance, RIV-FLOAT actually performs better than most standard round body rivet nuts. RIV-FLOAT’s size is a little bigger, which helps. Also, spin-out performance is improved too since the internal threads of the RIV-FLOAT help align the screw angle of the bolt during assembly.
“This dramatically reduces the cross-threading risk in the application and aids in speeding up assembly,” Pratt said.
Overall, RIV-FLOAT combines ingenuity, performance, and efficiency for a quality fastener that can improve the assembly and performance of any application. For more information, visit RIV-FLOAT’s product page, or contact us!
Recently, a customer of ours needed a special part in a hurry – and for good reason.
This closed end rivet nut was going to be used in a blood transfusion centrifuge that is used in the production of the COVID-19 vaccination efforts. If that wasn’t enough to expedite this order, the team in need of this part had a production line down.
Time and efficiency were critical.
The first email was received at Sherex Akron on a Monday at 12:03 p.m. explaining the dire situation. The small batch of products was made and shipped at 3:10 p.m. on Tuesday, ready to be used on the production line for Wednesday, with plenty of more on the way in the coming days and weeks to keep production running smoothly.
This was a fast, day and a half turnaround by the Sherex Akron team knowing how important this part is to hundreds of thousands of people who are suffering from this terrible pandemic.
“Thank you for making this an important situation within your company,” the customer said in an email. “Please extend my thanks to all the people involved with getting some parts ready to ship today.”
When Sherex said back in June that we were prioritizing projects directly impacting the mitigation and vaccination efforts of COVID-19 we weren’t kidding. This is just another example of the speed, competency and care, along with quality parts, the Sherex team delivered for our customer that we know will make a giant impact.
There are dozens of different body styles of rivet nuts on the market today, including-body, half-hex, and full-hex in shape with further variations to explore from there. However, for as many different body styles, there are also a wide variety of rivet nut flange types as well.
Standard flange types are typically round, large, and vary in thickness depending on whether or not the part is considered “heavy duty” or not. However, in applications calling for more flush installations to the installation pane, smaller (and thinner) flanges are offered as an alternative. For half-hex and full-hex parts, these flanges often take a hexagonal shape.
This heavy duty round rivet nut has a thick flange to prevent pull out
For increased spin-out resistance, hexagonal body styles are generally the optimal solution. This requires the ability to create hexagonal holes in your material to ensure a proper installation. If this choice is not available to you, there are flange features that assist as well. Many standard parts are also offered with wedges under the flange, which bite into the material.
This FHK hex-style rivet nut has a very small flange, but offers superior protection from spin-out
For harder materials that may prove more difficult to bite into, select series of rivet nuts come with a keyway under the flange, which provide another method to further lock the rivet nut into the material after it has been installed. However, the latter method does require the ability to create a corresponding allowance for said keyway in your installation pane.
a keyway under the flange helps the grip in this military grade rivet nut
So what’s your choice?
While many flange styles are designed for particular intent, they also contain their drawbacks, so be sure to consider trade-offs when determining your specific needs.
Standard large flanges offer suitable strength, but do not offer flush installation without any further processing. Small flanges provide more flush installation, but decrease parts’ resistance to push-out failure conditions – for an improved flush installation without this issue, countersunk-head rivet nuts are a choice, but also require the ability to process countersunk heads in your material. Wedged heads are ineffective in harder materials, while keyways require further precise processing of your material to fit the part.
While the number of choices may be staggering at times, it all comes down to the critical needs of your overall design. And, of course, for larger solutions, custom designs that deviate away from standard options to fit your exact geometric or performance needs are often viable. This may include modifications to the wideness or the thickness of the flange, or the addition of features like wedges or keyways.
Did you know Sherex Fastening Solutions is a Made in America Fastener Company?
Our manufacturing plant in Akron, Ohio makes millions of American made rivet nuts, compression limiters, and inserts for composites every year. Our parts out of Sherex Akron belong in some of the hottest vehicles on the road today, dozens of commercial and military aircraft, general industrial applications, and department of defense products. In fact, our Made in the USA rivet nuts were relied upon when companies pivoted to make products that helped mitigate the spread of the coronavirus, like hand sanitizer and ventilator stands, along with other critical applications for hospitals.
The CAT style rivet nuts has a low profile flange and can fit into a variety of different material thickness and material. This rivet nut could be a one fit solution if the material you’re looking to fasten has different thickness.
CAT Series Rivet Nuts
All NAS style rivet nuts are also made from our Sherex Akron location. The United States Department of Defense relies on Sherex NAS/MS rivet nuts for a variety of applications.
Our inserts for composite product line is used for structural attachments in plastic applications and are used extensively in the automotive and heavy truck industries as customer drive light weighting initiatives by switching to composite material for their components. In addition, Sherex adds compression limiters to these applications to ensure the mating component is not damaged due to the compressive force of the fastened joint.
NAS Style Rivet Nuts
Also, most custom rivet nuts are made out of Sherex Akron. With our staff of engineers and manufacturing facility, we’re able to see custom, American made rivet nuts from the design and manufacturing process all the way through quality control.
More upgrades are being made to the facility planned in 2020 to help increase capacity as demand as our Made in America rivet nut products continues to grow. More to come from Sherex Akron!
This was something no one saw coming. A pandemic that would shake up life for everyone around the world. As fast as the virus spread, families and businesses had to transition faster.
Manufacturers went from making cars to ventilators, t-shirts to masks, vodka to hand sanitizer, and we thank every single one of those businesses for it. The country, the world needed it – and Sherex is glad we could do our part to help.
Sherex Fastening Solutions went from supplying rivet nuts to some of the hottest new vehicles on the planet, to prioritizing its rivet nuts to manufacturers making products that make a direct impact in helping the world navigate through the COVID-19 pandemic. In total, four different rivet nut products went into applications that either directly helped patients or mitigated the spread of the virus.
Sherex’s rivet nuts went into were ventilator stands, hand sanitizers stands, and other critical applications used by hospitals.
“As an essential business, we have a duty to prioritize our products that will help fight this pandemic,” said Sherex president, Adam Pratt. “We’re happy knowing we can say, ‘hey our parts are in this application – we were able to help.’”
Sherex Akron, Sherex’s US manufacturing plant in Akron, Ohio, had an urgent requirement to produce these parts in short time. One of the parts Sherex Akron produced, part No. SXA25-80SPCA, is a flat head, open ended, smooth body rivet nut that installs into a stand specifically designed to hold up a ventilator. The customer was already using the part, but needed more, and needed them fast.
Ventilators are being used as a critical life saving device during the pandemic.
A more common Sherex part, part No. CAL2-580-3.3, is a knurled body rivet nut that belongs in a lot general industrial applications like refrigeration, heating and cooling units, and are used in the automotive industry. Now, they’re also used to create stands for hand sanitizers that will be used at malls, stadiums or any place with large gatherings so people will have ease of access to washing their hands.
The initial order of 30,000 rivet nuts was sent to the customer almost as fast as it was ordered.
Why are rivet nuts used and not typical nut and bolt? All were blind applications, meaning the attachment point could only be reached from the front – making it impossible to attach a nut to the backside of the bolt to keep the bolt secure. Also, efficiency. Once the rivet nut is installed, you just tighten the screw to attach your piece. Other methods are more time consuming, and during this pandemic, time is crucial.
“It felt good knowing that we could help and I know our employees had a sense of pride knowing they were helping too,” Sherex president Adam Pratt said.
For real and meaningful sales growth to take place, collaboration, cooperation and trust between the supplier and the distributor is extremely important.
This is why line walks and joint sales visits with supply chain partners at the end user are so vital that they are included in distributor rebate and purchase agreements. This allows both the distributor and supplier to get a better understanding of the project, processes, and to solve problems the end users are seeking help for.
Unfortunately, this doesn’t happen as often as it should. Distributors will often go to their supplier for a solution without providing all of the necessary detail to find the best solution. If suppliers don’t know the end product, that typically means the solution they provide is based on the limited information that has been provided to them.
Understanding that there is confidential information, it is quite common for us to execute non-disclosure agreements to work towards an improved solution that benefits all parties involved.
When working with a distributor at an OEM during a line walk, I witnessed a cumbersome assembly for a rivet nut, with the installer reaching for a machined washer to put under the head of the rivet nut prior to the installation. The washer served to raise the head of the rivet nut up just enough that the gasket which was applied to this outdoor housing would not be crushed during final assembly.
Because of a line walk, over 600,000 of this custom rivet nut have been used to help the end user save time and money.
Looking for a better solutions and explaining the details to the Sherex team, they were able to manufacture a taller profile head that acted as a spacer in the application thereby eliminating the extra machined washer. This saved cost, the need to manage another part number, increased throughput on that assembly line, and reduced worker fatigue. This resulted in over seven years of sales with over over 600,000 parts sold.
Real sales growth occurs for both parties when the supplier and distributor work together to improve an assembly method or fastener joint resulting in the lowest total installed cost and improved performance of the end product. Both the supplier and distributor gains the respect of the end user, more profit, and more opportunities for additional projects. This improves and solidifies the supply channel while elevating sales experience above the “commodity mentality.” Win-Win!
About Steve Urhausen: Steve has 43 years in the fastener industry and 25 years as owner of All American Systems. His work experience with importers, distributors, and manufacturers has helped him understand the “right fit” philosophy when trying to match a supplier to a customer. As a sales manager of two different companies, Steve was exposed to sales reps where he learned to respect and appreciate the value that they brought to suppliers and customers. Over the last 25 years as an independent rep has taught him humility, the value of hard work, and that follow through and communication are critical to success!
Now water will certainly speed up the corrosion process, but that shouldn’t eliminate the use of rivet nuts in wet conditions, or conditions where a rivet nut will spend some of its life submerged in water or fluid.
Our partner Tubtara® has a few different watertight and fluid proof rivet nuts that are designed with seals underneath the flange to keep water and fluids from leaking through the rivet nut. Tubtara’s Watertight HX series feature a O-ring seal mounted underneath the flange, and provides protection against moisture, oil, and dirt under high pressures. Despite the O-ring, it will deliver a metal to metal contact after installation.
Tubtara Watertight HX Rivet Nut. Notice the O-ring seal underneath the flange.
The Watertight (H)DPX Series is a rivet nut that has an applied sealant underneath the head. This non-reactive seal is resistant to many auto oils, antifreeze and other kinds of fluids with a higher viscosity. The seal in the (H)DPX Series can come in a variety of different seal material including NBR, Viton, silicone, epoxy based, acrylate and polyurethane resin.
Non-reactive seal is great for use in high viscosity fluids
Any application where you wouldn’t want water or fluid to leak underneath or through the rivet nut should require a watertight rivet nut. Without using one of the seals, whether it’s an O-ring or sealant, it may not be completely watertight – especially as corrosion begins to develop.
For more information on watertight rivet nuts, or if looking for a solution for fasteners that will perform well under water or fluid, contact us!
When it comes to rivet nut tooling, there are a variety of different options. While small-volume applications may often result in a manual hand tool being the best choice, larger-volume installation projects may require more robust tooling. Two of the most popular non-manual options are air-powered tools that install rivet nuts through either a spin-spin and spin-pull action.
Let’s go through the differences between spin-spin and spin-pull rivet nut installation tools.
Spin-Spin Rivet Nut Tool
A spin-spin rivet nut tool is an air-powered tool that, once a rivet nut is secured onto it, utilizes torque to spin its mandrel inward in order to collapse the rivet nut. The torque, driven by an air motor, ramps up continuously until the rivet nut fully collapses. After installation, the tool’s reverse trigger must be pressed to separate the tool from the now-installed rivet nut. In order to both maintain tool integrity as well as ensure proper installations, it is recommended that spin-spin mandrels be lubricated with wax.
The benefit of using spin-spin tools is that they are less expensive than spin-pull and can often be more lightweight, but its capabilities aren’t as complete as the spin-pull tool.
The installation base material can vary in thickness, but it is recommended that the rivet nuts being installed are thin-walled steel, aluminum or brass. Also, depending on what kind of spin-spin tool you purchase, it may often be limited in the thread sizes it can install. For instance, Sherex’s SSG-802 spin-spin tool is capable of installing parts with #10, ¼”, M5, and M6-diameter threads, and the SSG-803 is capable of installing 5/16”, 3/8”, M8, and M10-diameter threads. A hydro-pneumatic spin-pull tool is capable of installing all sizes between M3 to M10.
For a job that is consistently is going to use one part and one size, a spin-spin rivet nut tool would be a solid recommendation for the price.
Spin-Pull Rivet Nut Tool
A spin-pull rivet nut tool installs rivet nuts by pulling back its mandrel, rather than spinning it back. The rivet nut spins itself on to the mandrel, and then the mandrel pulls the threads of the rivet nut on to the base material, installing the rivet nut. The tool then spins the opposite way to release installed rivet nut. This tool is also referred to spin-pull-spin as explained in the two sentences before.
Sherex’s Flex-5 line of spin-pull tools is hydro-pneumatic, as the tool uses air and oil to install the part. A spin-pull tool can install everything that a spin-spin tool can, as well as more heavy-duty rivet nuts like full-body hex-style rivet nuts, European body styles, and stainless steel parts.
Another benefit of using a spin-pull tool is that it can install a wide range of thread sizes – from M3 through M10 for metric sizes, and from #4-40 to 3/8”-24 for inch sizes. You would need three different spin-spin tools to install that thread range!
For a job that is consistently is going to use one (compatible) part at one size, a spin-spin rivet nut tool would be a solid recommendation for the price. A spin-spin tool may be heavier and more expensive, but it is a far more versatile tool that can install more styles and more sizes of rivet nuts. All that is needed – for either tool – is the appropriate headset for the thread size you are trying to install.
Need help deciding between a spin-spin tool and a spin-pull tool for your next project? Contact us!