Above: Hansen Turbine Assemblies reduced cycle times by 40 percent after switching to Taurus carbide-tipped band saw blades from Wikus Saw Technology.

October, 2022- Manufacturer of power generation parts increases band sawing productivity with carbidetipped blades.

Purchasing new cutting tools typically makes more economic sense than buying a new machine tool to boost throughput. Tim Parker says Hansen Turbine Assemblies was able to avoid purchasing another band saw by buying Taurus carbide- tipped band saw blades from Wikus Saw Technology Corp. in Addison, Illinois. Taurus blades reduce cycle times by 40 percent while extending tool life, compared to the bimetal blades Hansen Turbine was previously using. “That saved about $100,000 on a new saw.”

Parker is the president and CEO of the Galax, Virginia-based manufacturer, which primarily services the power generation market. “We build anything for any steam or gas ground-based turbine aftermarket,” he says, adding that about 60 percent of the business is focused on gas and the rest on steam. In addition to manufacturing steam turbine, gas turbine and axial flow compressor components for the repair and maintenance of rotating power equipment, Hansen Turbine deposits surface finish coatings on parts for corrosion and erosion resistance.

The manufacturer’s main workpiece materials are heat-treated grades 410, 422, C450 and 403 Cb stainless steel, Parker says. Occasionally Hansen Turbine machines other metals, such as titanium. “The first machining step is sawing.”

Parker says the company switched from the previous bimetal blades after purchasing three Cosen band saws: two horizontals and one vertical.

In addition to those saws, Hansen Turbine has a large horizontal DoAll band saw at its 75,000-sq.-ft . facility, staffed by more than 50 employees. The saws run 24 hours a day, five days a week, plus overtime on weekends.

SEARCH FOR GAINS

To find band saw blades to boost productivity, the manufacturer turned to Southwest Tool Supply Inc. in Salem, Virginia. The industrial distributor recommended Wikus blades, and Randy Goss, a Wikus service technician, soon arrived to test several different blades, including the Selekta GS X3000 bimetal blade.

     Sawing is the first machining step at Hansen Turbine Assemblies.

After testing the Selekta GS X3000 bimetal blade on the new equipment, Hansen Turbine saw a run time reduction but was looking for a bigger gain. “We weren’t getting the productivity out of the saws that I felt they could,” Parker says.

Although the Wikus bimetal blade reduced cycle times, it did not extend tool life compared with the previous bimetal blade that Hansen Turbine used. Hansen Turbine then selected the Taurus carbide blade from the toolmaker’s line instead, even though it costs about 10 percent more. The benefit, however, overweighed the increased cost, Parker points out.

Wikus claims that its carbide band saw blades provide “excellent results in every application thanks to the different degrees of hardness and compositions of the carbides used, as well as long running times and extremely high performance thanks to the optimum carrier material for increased performance in case of capacity constraints.”

Besides increasing throughput, Parker notes that the carbide-tipped blade, which has a trapezoid tooth design, cuts straighter and imparts a finer surface finish than its previous bimetal blade.

“We cut the surface finish in half,” he says, estimating the finish improved from 250 to 125 root square mean (the average of the profile height deviations from the mean line). The carbide blade also eliminates taper across the stock, Parker adds, providing more surface contact when holding parts for subsequent milling operations.

After purchasing the Wikus blades, Parker says Goss spend a day or two training operators about recommended sawing parameters and what adjustments to make if they have issues. Hansen Turbine hasn’t experienced any issues to date after about a year and half of using Wikus blades, but the toolmaker is “extremely responsive” when needed. “We call Randy’s cell number, and he responds as soon as he can.”

      The Taurus carbide-tipped band saw blade has a trapezoid tooth design.

In addition to the pandemic making it more challenging to attract and retain band saw operators, which Parker describes as “extremely difficult,” Covid-19 made logistics and product availability “very problematic.” To ensure that Hansen Turbine doesn’t run out of band saw blades, which are exclusively from Wikus, he says the company stores about a month’s worth of blades, or roughly 20.

WEAR INDICATORS

Signs that indicate a blade is worn and ready to be recycled by a local scrapyard are longer run times, a need to increase sawing pressure and cutting at an angle or wandering off the designated tool path, with the latter occurring when a blade is extremely dull, Parker explains.

Although Hansen Turbine was able to avoid adding sawing machines by switching to carbide blades from Wikus, Parker says the manufacturer recently invested up to $3 million in five Okuma machine tools: a 50-taper horizontal machining center with six pallets, another large 50-taper milling machine, two 40-taper HMCs and a 50-taper vertical machining center.

To ensure that its band saws keep feeding all its machining centers at the required pace, Hansen Turbine will continue to purchase Wikus blades and rely on the tool manufacturer’s personnel. “They are honest and straightforward people,” Parker says. “I really appreciate that.” FFJ