Pittsburgh — Pet All Manufacturing Inc. is opening a showroom in Minnesota to display its big accumulator-head machines, a company official said at the Society of Plastics Engineers' Annual Blow Molding Conference, in one of two presentations on giant blow molders.
Andrew Hobson, USA technical manager for Pet All, said the company will use 10,000 square feet of space at custom extruder Nelson Plastics Inc. in Paynesville, Minn., near St. Cloud. The showroom will open in late November.
The showroom will house an accumulator-head machine that makes three-layer, 1,000-liter tanks (264 gallons), with a 74-pound shot.
Hobson said it's important to show customers how the big machine works. Pet All's Jumbo series of accumulator-head machines can have head sizes that can run up to 1,540-pound shots. The head tooling is huge, measuring up to 70 inches in diameter.
Hobson's presentation addressed how the Jumbo machine compares to rotational molding, the most common way to make very large hollow tanks and other vessels. Faster cycle time is the obvious advantage of blow molding over rotomolding. Hobson also said blow molding gives the ability to make multilayer parts, among other advantages.
Pet All introduced the Jumbo machines at NPE2018. The company, based in Markham, Ontario, was established in 1989. Pet All sources the blow molding machines from Asian manufacturers, he said.
The accumulator-head machines are made specific to each customer and are geared toward the end product.
Pet All offers more than the gigantic machines. The company sells a wide range of blow molding presses, including injection blow molders, injection stretch blow machines and reheat stretch blow molders — all of them fully electric.
Another speaker at the SPE blow molding conference, Andreas Amberg, technical director of Rikutec America Inc. in Whitinsville, Mass., said very-large-part blow molding began in 1970 with a heating oil tank. Then the technology grew rapidly, to now include water tanks, wastewater tanks, vessels for sewage treatment plants, kayaks and fuel tanks. Multilayer blow molding is common.
Amberg said the biggest challenge in very-large-part extrusion blow molding is forming the parison. A massive, heavy parison will stretch and distort, so Rikutec uses a discontinuous extrusion process.
"The challenge was to create a system where you could feed multilayer, accumulator melt into a discontinuous process," he said. Today, Rikutec can blow mold parts of up to 880 pounds and run four layers.
Rikutec America, part of the German Rikutec Group, has sold seven of the big machines in North America, mainly for septic tanks and intermediate bulk containers.