Fiber laser technology streamlines a centuries-old tradition
Michelle Avila
Long before the first Europeans landed on the eastern shores of North America, the end of winter meant the tapping of maple trees. Native Americans have long known that the trees held a sweet sap they could collect and boil to create a natural sweetener - Mother Nature's gift for surviving an always long, and sometimes grueling, northern winter.
Hundreds of years later, March still heralds the arrival of maple season in Eastern Canada and many northern states. Small "taps" or spigots are inserted into maple trees to release sap, which is then collected and boiled down into syrup - or in the case of the early Native Americans, all the way into sugar, which was lighter and easier to carry.
Modern equipment boosts efficiency
Though the process of collecting the sap and boiling it down remains the same, the equipment used has changed quite a bit, at least among the large-scale syrup producers. Reeds, wooden buckets, and open air fires have been replaced by hookless spouts, plastic tubing, and sophisticated evaporators to produce better-tasting syrup more efficiently.
A company that has witnessed and evolved with the industry is Leader Evaporator. This 125-year-old firm located in Northern Vermont is the largest manufacturer of equipment used to produce maple syrup in the U.S. Although Leader Evaporator makes equipment for an industry hundreds of years old, the equipment it uses couldn't be more modern. In fact, up until three or four years ago, the technology the company now uses didn't even exist. That equipment includes a HyIntensity fiber laser metal cutting system which it uses to produce parts for the evaporators that help extract water from the maple sap, leaving only the syrup and sugar behind.
Leader Evaporator turned to fiber laser for a number of reasons. First, fiber laser could cut a wide range of different materials including the polished stainless steel, mild steel, and aluminum used to build its evaporators. The ability to cut polished steel was a real selling point for the company since steel is a critical material for its business. In addition, the company was impressed with the speed and cut quality delivered by the fiber laser system.
"The combination of our Hypertherm system on an AKS AccuCut table produces very precise cuts for clean welds when assembling our evaporators," said Alan Ball, a project engineer at Leader Evaporator. Another benefit for Leader Evaporator was the fiber laser's price. Fiber lasers offer the speed and cut quality of more traditional CO2 lasers, but cost significantly less to purchase, operate, and maintain.
"Fiber laser systems cost less than a CO2 system because the delivery of the laser beam is so much more efficient," explained Doug Shuda, a product marketing manager at Hypertherm, the company that makes the system used by Leader Evaporator. "A 2.0 kW fiber laser system, for example, delivers the same cutting capacity as a 4.0 kW CO2 system so the customer is able to buy a smaller, less expensive system, without sacrificing cutting performance."
The associated "chiller" used by all laser systems is also smaller and less expensive than the chiller for a comparable CO2 system. Due to the solid-state design as well as the higher energy efficiency (70% higher), the cooling requirements for fiber laser are much less. In addition, because fiber laser beams are delivered via a fiber cable and do not rely on mirrors to move the light beam, the less restrictive fiber laser's delivery systems enable laser integration on a broader range of cutting table designs and size configurations. It is entirely possible to install a fiber laser system onto an existing plasma cutting table, provided the table has good motion and acceleration capabilities.
Operating and maintenance costs are also lower thanks to a higher wall-plug efficiency. For every unit of power that passes through a CO2 cutting system, only 8-10% is actually used. With fiber laser, power efficiency averages 31%, making it 86% more efficient than a CO2 system. As a result, utility bills are lower, not only because less power is needed to operate the table, but because cooling requirements are significantly reduced.
Maintenance upside
Another benefit of fiber lasers are that they require little to no maintenance since they don't rely on mirrors or turbines. Traditional gas lasers require regular maintenance: Mirrors need to be maintained and calibrated; resonators and turbines that move the gas need to be replaced; and the lasing gas needs to be cleaned out regularly because of its tendency to collect impurities. All of this maintenance adds up; on average a CO2 system can cost up to $40,000 per year to maintain. End-user market analysis shows annual beam alignment and CO2 system maintenance can theoretically range from $0 (for the owner who does not maintain the system even though that owner is risking increased system downtime) up to $80,000 (for the owner who has laser engineers on staff to maintain the system[s]). Prior to getting the fiber laser online, Leader Evaporator was faced with quite a bit of system downtime. The company estimates its old oxygen plasma system was down 15-20% of the time, so in a typical five-day work week, one full day could be wasted. All that downtime, plus a cutting method that wasn't as fast as it could be for the super thin metal being cut, slowed Leader Evaporator's production, causing orders to pile up. In some cases, Leader Evaporator found itself having to turn away work. That's all changed now. Today, Leader Evaporator is enjoying record business, having posted its best year ever in 2011 and expecting to meet or beat that record in 2012.
Although fiber laser is responsible for much of the increased capacity since the system experiences virtually no downtown and the cutting method is so fast, Leader Evaporator's usage of what is called an "integrated cutting solution" is also helping. By using other Hypertherm components alongside its fiber laser system - in this case, a computer numerical controller (CNC) that controls the x-y motion of the cutting torch, a torch height control (THC), and advanced nesting software - Leader Evaporator is able to multiply the benefits its system delivers.
"Instead of each component doing its own individual job, the four components (fiber laser, CNC, THC, and software) work together for increased performance," explains Hypertherm's Shuda.
Increased performance
Leader Evaporator is able to take on more work since it is now able to cut more parts - in some cases up to twice as many parts than what was previously possible. Another benefit is that the company can now cut perfect holes that are ready to accept bolts in seconds.
"We are doing so much more today than we've even done before. The ability to make precise cuts on stainless steel, galvanized steel, and aluminum, perform fine feature cutting, and cut perfect holes is enormous," according to Ball, the project manager at Leader Evaporator. "On top of that, we are saving so much time because the cuts are so good that we don't have to spend time cleaning up any of the cut parts."
Bell was also impressed by how easy it was to get his new system up and running: "It was much quicker and easier than I anticipated since the components we used were all from Hypertherm and designed to work together."
For Leader Evaporator, the switch to fiber laser and an integrated cutting solution means much more than better quality cuts, increased capacity, and lower operating cost. It means that instead of juggling orders and outsourcing jobs, the company is able to once again concentrate on the job it feels is most important: making the best evaporators in the business.
Michelle Avila ([email protected]) is public relations manager at Hypertherm. Photos by Wayne Tarr.