Written by Valley Forge’s James Brooks

Controlled bolting has for many years been associated with critical bolted joints. The term is more often applied to the act or procedure of installation than to the life cycle of the bolted joint.

Application, measurement and control of torque has also been the predominant challenge for users of controlled bolting methods.

Installation methods have been designed to deliver torque-based final results. They have required the use of tooling with controlled output settings and with highly specific procedures in an effort to deliver reliable, repeatable (word choice? replicatable/reproduceable) clamp loads.

A shift in thinking to controlled bolting is taking place in many industries:

The use of direct tension measurement and control, versus torque, is growing.  Inherently more accurate, tension control only uses torque as the “driving force” used to rotate and tighten a bolted joint.  If measured directly, it can be used simply and quickly to manage torque-based equipment output.

But after the installation, can the bolted joint be controlled?

We do not have bolts that tighten themselves, yet, but using tension-based load monitoring fasteners is a reality.  With the same benefit over torque, tension-based monitoring is more accurate.

Condition monitoring is the most costly part of controlled bolting. Factors include; inspection frequency, accessibility and equipment downtime, to name just a few.

The use of Valley Forge’s SPC4 tension indicating technology is playing a large part in driving these changes in controlled bolting installation and post-installation thinking.

Once installed, an SPC4 bolt or stud can be considered as the “foundation” from which a menu of interchangeable inspection options can be chosen. With a standard reading surface across all sizes of bolt or stud, different readers can be used as required or desired.  They include:

  • Manual, snap-on readers both in-line and right-angle.
  • Wired electronic readers with data collection options and output control for torque tightening equipment operation.
  • Blue tooth enabled readers.
  • Hard-wired remote readers.
  • Pre-programmed wireless readers for remote monitoring, including WiFi and Low Frequency options.
  • Wireless Low Frequency readers that have internet user interfaces and can be programmed to send an alert if a bolted joint tension level is reached i.e. using the IOT, critical bolted joints can talk to you if they are having a problem: or are about to have a problem.

These options are taking the cost and complexity out of condition monitoring of critical bolted joints.  They are now controlled for life.

Want to know more?  Contact us today.


For more information or discuss what this means for your bolting application, please reach out to our sales team anytime at sales@vfbolts.com.


Visit us at booth 4638

We are happy to be exhibiting at PowerGen International again this year. This event shows great promise and we hope you can stop by and see us! We will have both the MaxboltTM and SPC4TM load indicating fasteners with us and would be happy to give you a demo and answer any questions you may have. This is a great opportunity to see first hand how LIFs can revolutionize your bolted joint, no matter the application.

If you would like us to help you register for a free pass,  please reach out to us using the form at the bottom of the page.


About POWERGEN International

POWERGEN International exhibition and summit serves as a business and networking hub for electricity generators, utilities and solution-providers engaged in any or all of the multiple cross-sections of power generation. The exhibit hall provides an interactive experience that can be personalized to connect attendees with the latest technology and innovations in the conventional and renewable electricity generation markets from around the world. The summit and knowledge hubs deliver transformative content including disruption caused by the emergence of renewable and decentralized power, niche technologies and the latest in policy and economic trends.

PowerGen International’s goal isn’t to say they are the biggest and best event in power generation today. It’s to be it – for their customers – for years to come.

To learn more about PowerGen International, please visit the show website.


Request A Free Pass


Published courtesy of Torq-Comm International Inc.

Whichever way you tighten a bolt, be it with a spanner, a hand torque wrench, a hydraulic torque wrench or tensioners, the ultimate goal is the same, a tight and reliable joint.

If you aren’t a tool manufacturer and can take an unbiased view of all of these tightening methods, there is really only one conclusion you can make. They are all filled with potential pitfalls, that may have a negative effect upon the integrity of a joint. This has been a contentious issue in the bolting sector for many years, but the reality is, there is only one cast iron way to ensure your joint is reliable – residual bolt load.

Certainly, with the measured methods used to tighten a bolt, your goal is to stretch it to a pre-determined point, resulting in a tight joint that hasn’t been overloaded, and contains the correct amount of residual load. There are so many factors such as lubricant, bolt quality, human error, equipment inaccuracy and many more, that the only true way to absolutely guarantee the reliability of your joint, is to know the residual bolt load, period.

Wouldn’t it be great if there was a system out there that could provide technicians with flange working instructions on site, guide them through the bolting process, ensure they tighten in the correct sequence, securely gather the bolting data real time AND confirm the residual bolt load? That would be the ultimate bolting system, right? Well now you can!

Introducing the new Torq-Comm Commander XTV1000. If you are involved in the industrial bolting sector, you will already be aware of the existing Torq-Comm Commander process control and data collection system, which is now being widely used to improve joint integrity assurance. The XTV now takes things a step further. The “X” stands for rugged durability and the “T” for torque (including hand torque) or Tension. The additional “V” stands for verification.

Torq-Comm International has quite literally entered into a “joint” venture with world renowned fastener manufacturer, Valley Forge. For many years, Valley Forge has designed and produced load indicating fasteners. More recently, they have developed the SPC4™ Load Indicating System. The system uses similar technology to standard load indicating fasteners with one really smart difference. The residual load data can be gathered from the fastener and exported by Wi-Fi or Bluetooth.

The new Commander XTV1000 controls the bolting process, collects and securely stores the data, and then communicates with the SPC4™ to verify the residual load. There literally is nothing else available that offers this level of control and verification, during industrial bolting operations.

Michele Clarke, CEO at Valley Forge commented “We are delighted to be working with Torq- Comm, collectively, we will undoubtedly bring a new level of safety and reliability in the bolted joint, never seen before.”

Bret Halley, COO added “We have been working hard on creating innovative products to help with joint integrity assurance. As soon as we saw how the Torq-Comm Commander XT system worked, and the potential synergy between our organisations, we knew we had something really special between us.”

Paul Iannello, CEO at Torq-Comm International said “We have always known that our system was going to kick off a revolution in industrial bolting. Now we are working with Valley Forge, the ultimate solution is available to the sector. I couldn’t be more excited about the future for all concerned.”

A great example of two industry leading organisations bringing the ultimate solution for joint integrity assurance, guaranteed.


For more information or discuss what this means for your bolting application, please reach out to our sales team anytime at sales@vfbolts.com.

To learn more about Torq-Comm International, please visit their website at torq-comm.com.


Even though the use of a VF Maxbolt or SCP-4 provides the most accurate indication of clamp load (since it indicates direct tension), if you are using the torque method to tighten the joint you should still consider the merits of lubrication.

Since torqueing the fastener will involve rotational forces, the need to overcome friction will be important in order to deliver the optimum force to achieve the desired clamp load.  Friction losses can been significant, so applying a light film lubricant to the fastener threads and under the bolt head will help reduce such losses and help in improving repeatability and accuracy of the process.  Lubrication will not affect the clamp preload.

The good news is, since you are using a Maxbolt or SPC-4 product, you will know within a +/- 10 accuracy tolerance your direct tension or preload.


Valley Forge is proud to announce that we have partnered with Curtiss-Wright to bring our industry-leading load indicating fastener technology to the nuclear and general power generation industries.

It is our passion to see the evolution of the bolted joint where the accurate assembly and our continuous load monitoring capabilities reduce the potential for premature wear, expensive downtime, and catastrophic joint failure. We believe that this new and exciting partnership will help to do just that.

The partnership will take our patented load verifying technologies and pair them with the bolting and sealing solutions offered by Nova and AP Services. We believe this combination will be a powerful force in the nuclear and fossil power generation industries.

As a service brand of Curtiss-Wright, Nova and AP Services have been supplying ASME Code, safety-related and quality critical fasteners, precision-machined components and fluid sealing solutions to the nuclear and fossil power generation, Department of Energy, Nuclear Navy and petro-chemical industries for over 30 years. The Nova/AP Services team has been energized by the addition of the Valley Forge product line and the expectation they will be solving problems in our customers’ most demanding applications.

For more information or discuss what this means for your bolting application, please reach out to our sales team anytime at sales@vfbolts.com.

To learn more about Curtiss-Wright please visit their website at curtisswright.com.


City of Phoenix’s very own local news channel, PHXTV, is running a television segment, Made In Phoenix, showcasing local manufacturing companies in the Valley. We were very fortunate to be asked to be the first company featured. Our Chief Executive Officer, Michele Clarke, shares with the News Reporter the Valley Forge & Bolt Mfg. Co. history, growth and the need for more skilled manufacturing employees. There is a hiring surge in the manufacturing industry. Check out our careers page or submit your resume to careers@vfbolts.com. Come work for one of the most rewarding industries, manufacturing. That’s not all – you’ll be working for the most innovative bolting companies around.