Aerospace

US-based Load Control Technologies is a leader within the fastener load measurement sector, with its next generation of ultrasonic fastener technology, the i-Bolt®, providing accurate load inspection for all fasteners. Here Mason MacDonald, customer support manager at Load Control Technologies, tells us more about the company and its capabilities.

How was Load Control Technologies established and what have been the key developments over recent years?

“Firstly, I must provide some context, Load Control Technologies is an Innovation Plus LLC company.  The company was founded in April 1990 as a partnership. In 2003 the name Load Control Technologies was adopted. Typically, any mention of Innovation Plus generally refers to the company prior to 2003.

With that in mind, Innovation Plus was responsible for the conception and proof of feasibility of the ultrasonic fastener technology, which was later commercialised as the Ultrafast® Intelligent Fastener® technology. This technology utilised a piezoelectric thin film coating, which is applied to every fastener as a finishing operation, to directly measure load in the fastener using an ultrasonic pulse echo technique. Innovation Plus proved feasibility of Ultrafast technology through initial funding from a Ben Franklin Partnership Innovation Award and a NASA contract with the Marshall Space Flight Center.

Load Control Technologies continues to demonstrate its technology leadership in the field of fastener load measurement through the recent introduction of its next generation of ultrasonic fastener technology, the i-Bolt® Fastening System, with greatly enhanced capability, broader application and lower cost. This new technology provides accurate load inspection with all fasteners and has applications in the automotive, aerospace, construction and other industries. This major advance in ultrasonic transducer manufacturing technology enables licensed fastener manufacturers to deliver high volume ultrasonic fasteners at lower installed cost.

Whilst we are a US-based company, we also have facilities in Bergara, Spain, which enables us to provide fast fulfillment and delivery of bolts and assembly tools. For instance, both our US and Spanish facilities are capable of producing fully qualified development i-Bolts in as little as two days.”

How does this ultrasonic fastener technology work? What are the key features?

“Load Control Technologies delivers long-term solutions to critical joint and assembly process control problems in the aerospace, automotive and energy industries. This is often achieved by using the i-Bolt Fastening System, allowing fastener load to be measured and controlled during tightening. This means that customers can assemble a critical joint to specification, with 3σ accuracy, in less than a second, all while using an impact wrench. This capability revolutionises the assembly process and opens the door for what is potentially the highest volume IOT device in the world, the i-Bolt.

i-Bolt technology equips end users’ fasteners with a low cost permanent ultrasonic transducer (only 50 microns thick) at the top or bottom of each bolt. Form, fit and function of the fastener is unaffected. The permanent transducer enables load controlled tightening, tightening load monitoring, and load inspections, throughout the life of the joint with near perfect repeatability and ±5% (3σ) inspection accuracy.”

What are the benefits to customers of using your products? In what applications can they be used?

“Current torque tightening methods provide ±30% – 50% accuracy, depending on material. Many industries, primarily aerospace, would never accept a process control variation this large. The i-Bolt provides direct load measurement with ±3% – 5% accuracy in both assembly and inspection.

i-Bolt technology is often used in development to better understand the behaviour and long-term integrity of bolted joints. Inevitably, in critical applications, the question is asked ‘why aren’t we using this in our production?’

When people adopt this technology, they are surprised to find out how inaccurate and inadequate their previous methods are. When you can achieve such an improvement in manufacturing process control, it is extremely difficult to justify returning to those previous methods. Eventually, all critical bolts will utilise IOT technology to indicate how tight they are.”

How important is quality and testing when it comes to fasteners? Have demands for reliability changed over recent years?

“Load Control Technologies is concerned with addressing process control variations in tightening methods providing ±30 – 50% accuracy. With such a huge variation, the only way to safely account for this is to over design a joint for the worst-case tightening conditions. This results in reduced control, unnecessary weight, as well as lengthy assembly times.  With direct load measurement, providing a significant improvement in tightening control, critical joints are designed to precise load and tightened and inspected in seconds. This is where our motto derives from ‘Design to load, tighten to load, inspect to load.”