Quality and precision are important across the manufacturing industry, but they are especially vital when it comes to any component that will be going into aircraft. As a supplier to some of the world’s most demanding aerospace and defence OEMs, Lovitt Technologies Australia (LTA) knows this better than most companies, and it invests in the latest technology to ensure it continually surpasses its customers’ expectations.
Founded in 1954 as George Lovitt Manufacturing, LTA initially established itself as a manufacturer of cutting tools for the automotive industry. Over the ensuing six decades it has evolved continuously, being quick to anticipate the eventual decline of Australian car-making and branching into fields as diverse as communications, defence and food & beverage. However, it has been in the field of aerospace that the company has really specialised – and made its name – over the last 20 years.
Today, aerospace components account for around 95% of LTA’s business. In the commercial aviation sector, the company is a key supplier to Boeing, working on the 787 ‘Dreamliner’ – LTA’s biggest program – as well as the 747 and 737 airliners. In the defence space, the company supplies parts for the Lockheed Martin F-35 Lightning II joint strike fighter, the Boeing F/A-18 Hornet and F15 Eagle fighter jets, the V-22 Osprey V/STOL military transport aircraft, P-8 Poseidon and the CH-47 Chinook helicopter. It also supplies some components for smaller commercial aircraft such as the Gulfstream private jet.
“We are on a large variety of flying platforms,” says Bruce Ramsay, LTA’s Manufacturing Director. “We make flyaway parts – major structural components that go on aircraft.”
Recent years have seen LTA undergo significant expansion, as the 787 program has settled into a steady rate production, and while other work in defence areas with Boeing and Lockheed Martin has increased. The company’s workforce has grown substantially, from 49 employees in late 2013 to a current headcount of 112. Capability has also been broadened with the acquisition in 2013 of Electromold, the only company in Australia that can prepare and coat components to Boeing and Lockheed Martin specifications in a production environment.
From its manufacturing facility in Montmorency, Victoria, LTA produces a diverse range of complex structures, working primarily in aluminium and titanium, metals whose lightweight properties makes them vital in aerospace applications. The company specialises in machining highly intricate components, with an emphasis on diagonal lines and slanted planes – characteristics that instil a greater degree of strength in a component than simple right angles would.
Parts of such complexity need to be produced accurately, particularly when you’re relying on them to keep your aircraft airborne. Consequently LTA employs cutting-edge quality & inspection technology to ensure every component that leaves its workshop meets design specification. Its latest acquisition has been a co-ordinate measuring machine (CMM) from Mitutoyo, supplied by MTI Qualos.
“We had a Mitutoyo CMM that we’d been working with for the last 20-odd years,” says Ramsay. “The reason to buy another is the back-up service we get from MTI Qualos, and the machine itself and its reliability. The Mitutoyo CMM has been good, and that heavily sways the decision to buy the same brand. This machine is to increase our capacity in the CMM area as our workflow demands.”
Everything in its right place
The new machine is also equipped with a SurfaceMeasure non-contact line-laser probe from Mitutoyo. The SurfaceMeasure is a lightweight, high-performance probe designed to automatically compensate for environmental variables as well as workpiece characteristics. It enables CMMs to efficiently obtain workpiece shape data, even from artifacts with complex and/or rounded geometries. It uses digital signals to eliminate effects of signal deterioration over distance, thus enabling high measuring speeds. Data is captured at 75 lines per second over a measuring area of 60mm by 60mm.
The decision to procure the SurfaceMeasure reflects the latest evolution in LTA’s strategy. Recently the company has begun moving up the value chain by diversifying into minor assembly work. Rather than simply providing individual machined components, the company now delivers fully assembled structures, with as many as 50 or even 100 sub-components attached.
Ramsay points out a floor structure from the F-35 joint strike fighter as an example. The main structure is intricately machined from a single piece of aluminium – the components that LTA produces can often comprise as little as a tenth of the original workpiece from which they were machined, the remainder ending up as swarf. Mounted on that structure is a variety of brackets, supports and other sub-components, of differing sizes and orientations.
Most of us have experienced that sinking feeling when you’ve bought a piece of furniture from Ikea, got it home and assembled it, and when you’re done you’ve got one screw left over and you’re wondering where it was supposed to go. This might end up with a slightly wonky table or a rickety wardrobe, but there’s no room for such error in aerospace, and LTA’s customers wouldn’t tolerate such mistakes. Therefore, making sure that every one of those parts is present in its correct positions is essential. However, this does not require the same degree of precision as a machined component.
“From a machine tolerance point of view, machining of a component, the tolerances can range from basic structures of the part of +/– 10 thou (thousandth of an inch: 25.4 microns),” says Ramsay. “And then in various features you can have as tight a tolerance as +/- half a thou. And its relativity to some other feature may be quite tight. Its relativity to each other is very important because it’s how the structure performs.
“Assemblies generally are not as tight a tolerance as they may be +/- 20 or 40 thou, because the position of where a bracket holds a wire isn’t as vital as the strength of a structure. They’re generally more relaxed tolerances, and therefore that’s why you don’t need to check it to that degree.”
For inspecting its machined parts, LTA uses contact probes, which deliver a very high level of precision, but take a relatively long time to do it. The Surface Measure laser probe does not achieve the same degree of accuracy as a contact probe, but it is much faster. For the assembled structures LTA produces, this is a worthwhile pay-off, saving considerable time while delivering the required degree of precision.
“We added the laser scanning equipment as the next step,” says Ramsay. “We felt for a lot of our assembled items, it is a very efficient, definite and speedy way to check that we’ve got the assemblies correct. We’ve got the brackets facing the right way, they’re where they’re supposed to be; they’re not where they’re not supposed to be. And the fasteners are the right length in the right position, we’re not missing a fastener.
“If you’ve got a +/- 40 thou tolerance, it seems silly to check to an accuracy of .0001. So we don’t need to check to that accuracy, this enables us to speed that process up. It’s basically an electronic set of eyes to quickly go over the part and check that we’ve got it assembled correctly.”
Often this is simply a case of making sure everything is in its right place.
“One of the major things is ensuring the bracket is there where it’s supposed to be. Very rarely will we have an issue where the bracket is slightly out. We’ll have an issue where the bracket is missing. From our point of view, it’s critical that nothing could ever leave our place without knowing everything is correct.”
Untapped potential
LTA had the new CMM and laser probe up and running from the day it was installed, putting in programs and checking parts, and Ramsay has been impressed with the way it has already speeded up processes in its quality & inspection department. However, he stresses that it is still too early to try and quantify the benefits it has delivered as his team are still getting to grips with the technology and what else it can do.
“There are lots of things we can do to make our laser measurement more efficient, such as speeding up over sections where we don’t need to be measuring anything,” Ramsay explains. “We haven’t fine-tuned it. We’ve had lots of training from MTI Qualos, but we’re still learning ourselves how to apply that training to our parts. And we’re still developing that.”
Nonetheless, Ramsay sees great potential in the technology that LTA can exploit. In addition, this hasn’t gone unnoticed with the company’s customers.
“I can see lots of improvements we can make from where we are today, but it gives us great efficiency,” he says. “And Lockheed Martin is very excited we’re doing this type of thing. When they see you’re that committed to making sure your parts are right. We could do it other conventional ways, but if you’re making a financial commitment to the quality of other peoples’ parts, they generally appreciate it.”