By: Bill Bregar
July 10, 2013
Evco Plastics is injection molding parts — big parts — on a two-platen Engel press with 3,500 tons of clamping force installed earlier this year at Evco's plant in Oshkosh, Wis.
Evco expanded its Oshkosh factory by 30,000 square feet last year, with high ceilings and an 80-ton crane for handling big molds. The Oshkosh plant now measures a total of 100,000 square feet.
"What we did in Oshkosh was really prepare for the big stuff," Evco President Dale Evans said. "Not only do you have a big machine, you've got a big mold and a big crane above it. So you need a lot of clearance."
Before the 3,500-tonner, Evco's largest injection molding machine was a 3,300-ton press, also in Oshkosh. Evans said that when that machine hit 80 percent capacity utilization, it was time to get the 3,500-ton Engel.
The new press boosts Evco's capacity to mold parts for the power-sport, agriculture, automotive/trucking and military markets.
"We're one of the very few plastics manufacturers in the Midwest with access to this size machine," Evans said.
The servo-hydraulic hybrid press is energy-efficient. It uses only as much energy as required for any production phase, then consumes no energy from machine movement during the cooling time and other parts of the cycle.
Evans said energy efficiency was built into the overall plant expansion, with skylights and new lighting, and an energy-sipping chiller. Saving energy is even more important for large presses. "You don't want to turn on the machines, and the lights of Oshkosh dim," he joked.
The big Engel press is equipped with a robot from Hahn Automation GmbH. The Hahn PL-1000 three-axis beam robot has a two-axis servo wrist, which swivels to help the robot handle oddly shaped parts. Evans said the press moves parts to the end of the machine, rather than to the side, so save space.
The press also uses Stäubli magnetic platens, for easier installation of the large molds, and faster mold changes.
Evco is based in DeForest, Wis. Companywide, Evco runs 148 injection molding machines at nine plants, in clamping forces ranging from 28-3,500 tons.
Evans said company officials are thinking about adding even larger-tonnage presses in the future.