Schoeneck Containers, Inc.’s compressed air system in Delavan, Wisconsin, features ducting and louvers for heat recovery during the winter. The configuration also routes hot air out of the facility’s mechanical room during warm months (Photo courtesy of Zorn Compressor & Equipment)
When compressed air is essential to the production of up to one million plastic containers per day there’s little room for error. That’s why Schoeneck Containers, Inc. (SCI) leaves no stone unturned to ensure its compressed air systems run smoothly at all times and without fail at its bustling facilities in Wisconsin.
“As far as production, my focus is maintaining constant pressure and always having the availability of air,” said Bill Bushman, Facilities Engineering Manager at SCI. “My other big focus is keeping an eye on misuse of compressed air. That’s just a waste of air and the cost involved. Anytime we can save energy it helps us be more profitable.”
All the while, SCI (www.schoeneck.com) pays close attention to customers’ needs whether it’s ensuring product quality or helping speed time to market – all of which explains its robust growth as a supplier of containers for use diverse applications, including food and beverage, personal care, household, industrial, nutriceuticals, wipes and pet care products.
Tailored Compressed Air Systems
SCI’s growth is evidenced by the construction of a 250,000-square-foot production facility in 2019 in Delavan, Wisconsin. The new plant is in addition to the company’s 172,000-square-foot headquarters and production facility in New Berlin, Wisconsin. The company has been in business since 1972 and employs 260 people.
The New Berlin plant houses a total of 30 blow molding production lines. The Delavan plant, which is built to accommodate continued expansion, includes four blow molding lines and two injection molding machines operating 24 hours per day, seven days a week. Both plants produce high-density polyethylene or polypropylene containers, ranging from four to 320 ounces. The Delavan plant also injection molds caps and closures. The compressed air systems at SCI are tailored to each operation.
The centralized compressed air system at the New Berlin plant includes four, 300 horsepower (hp) centrifugal air compressors and a 200-hp, Variable Speed Drive (VSD) lubricated air compressor. It also consists of refrigerated cycling dryers for each air compressor, as well as three dry storage tanks, including 1,500- 1,600- and 3,000-gallon units.
At the Delavan operation, SCI worked with Zorn Compressor & Equipment, Pewaukee, Wisconsin, to design and install a centralized system located in the facility’s large mechanical room. The system is comprised of two, 200-hp, oil-free rotary screw Kobelco KNW Series air compressors; two refrigerated cycling dryers; two pre-filters, rated at 1 micron each; two after-filters, rated at 0.01 micron each; and a 3,800-gallon dry receiver tank.
The compressed air system at SCI’s Delavan plant includes a 3,800-gallon dry receiver tank. (Photo courtesy of Zorn Compressor & Equipment)
Additionally, the air-cooled air compressors at the new plant are configured with ducting and louvers to heat the mechanical room during cold months and exhaust hot air outside the building during warm months. It also includes a flow meter to monitor and measure compressed air use so decision makers can accurately determine when to expand the compressed air system. As with the New Berlin facility, the Delavan plant uses an aluminum piping system to distribute compressed air throughout the operation.
The Delavan compressed air system is designed identically with two refrigerated cycling dryers and other key components for full redundancy. (Photo courtesy of Schoeneck Containers, Inc.)
Constant and Reliable Air
Whether used for blow molding or injection molding, the compressed air systems at each plant are designed to provide highly reliable air with ample capacity to meet production goals – in addition to providing redundancy.
At the New Berlin plant, the three centrifugal air compressors operate at near capacity at all times, while the VSD rotary screw unit serves as a trim unit to provide additional air when needed. The fourth centrifugal air compressor serves as a backup machine. In Delavan, each air compressor is rated to deliver 814 scfm of compressed air at 110 psi. As such, one unit alone provides more than enough air to meet the plant’s 600 cfm peak capacity, while the second machine provides full redundancy.
SCI’s continuous extrusion blow-molding process is the biggest consumer of compressed air. The ability to maintain a steady supply of air at stable pressure is crucial, said Bushman.
“We’re using compressed air to form the containers and the pressure and volume needs to be there,” he said, noting pressure for the process typically fluctuates from 95 to 100 psi, depending on the size of the container. Compressed air, he added, is key to the integrity of the product. It’s why the SCI team is automatically notified of any drop in pressure.
“When that container has a snap cap, for example, you have to size the bottle correctly so the caps fit when they go to package and fill it. The same is true with a screw-on cap. We need to make sure those threads are within specification so the caps fit correctly,” Bushman said.
A constant and reliable supply of compressed air is equally essential for the injection molding process. Air primarily powers pneumatic valves on the plant’s automatic robotic pick-and-place system, which transfer caps and closures throughout the production and packaging process. Compressed air is also used at both plants to actuate valves of the plant’s extensive vacuum system, which conveys plastic resins from rail cars outside the buildings to hoppers and blenders inside and onward to dedicated processing lines and machines.
“It’s a continuous process,” Bushman said. “Any one production line is capable of drawing close to 1,000 pounds of material per hour. My main concern is having that compressed air capacity.”
Equipment and Supplier Selection
To ensure the availability and reliability of compressed air at both plants, Bushman carefully evaluates equipment and technologies regularly and matches them to the precise needs of the operations. He also looks at the big picture.
“We look at all aspects of equipment selection, including the operating and lifecycle costs of the equipment,” Bushman said, pointing to the oil-free air compressors specified for the Delavan plant. “The maintenance interval is 8,000 hours for these units whereas we’re looking at 2,000 to 3,000 hours between intervals on some of our other compressed air equipment. That really helps with maintenance costs.”
What also helps ensure a dependable supply of compressed air at all times is a preventive maintenance contract with Zorn and a strong relationship with the firm, Bushman said. He also credits his own team for keeping equipment in top condition.
“We’ve got people at both plants with eyes on equipment at all times,” he said, adding how he appreciates the expertise of Zorn. “Between the two of us we have a good handle on how our equipment is running. But with Zorn, for example, if we have a question about how something operates, or we want to know what we can do better to make sure our equipment is up to speed, it’s as simple as making a phone call.”
Josh Susee, Zorn’s Business Development Manager, said Zorn appreciates working with SCI and Bushman in particular given his knowledge and expertise in compressed air.
“Bill and SCI always do it the right way,” said Susee. “By ‘right,’ I mean they don’t take shortcuts. For instance, they chose the most efficient and the most reliable system they could reasonably get for the new facility. They always look for the best system for the value, and with the new facility, they’re now able to enjoy the advantages of the installation.”
Ongoing Progress in Sustainability
What SCI also aims to get right is sustainability, whether it’s making educated decisions related to equipment selection or efforts to conserve resources at every level of the operation. A prime example is the company’s Green Team, which it recently formed to explore all avenues of sustainability.
“The team consists of almost every area of the company,” Bushman said. “It includes engineering, quality control, production, human resources. We want the team to include someone from every area so we can get an accurate measurement of what we’re using as far as resources. That way, we can determine where we can best save in all areas, such as the amount of paper we’re using for business purposes, the amount of energy used for compressed air, or water for cooling processes.”
Minimizing misuse of compressed air is high on the list of sustainability efforts at SCI – and a top priority for Bushman.
“For example, say we have a large container that doesn’t run through the conveyor system quite like it should because we normally run smaller containers in that same system. In that case, an operator might connect an open compressed air line to the conveyor to temporarily push it down the line. So I always make sure those types of stop-gap fixes don’t become a long-term solution. If compressed air is not doing work it was designed to do such as operating a valve or blowing a mold, it’s a waste of air and it can be costly.”
Bushman said many at SCI already have an appreciation for compressed air since the company has worked with Zorn and Focus on Energy on successful leak detection programs. Focus on Energy (www.focusonenergy.com) is a statewide program in Wisconsin that offers information and financial incentives to help businesses select and install cost-effective solutions designed to save energy and money.
Zorn conducts the leak detection program for SCI because the compressed air supplier is an expert it – and it offers tremendous value to customers, said Susee.
“We’ve got the people and the tools to get it done without interrupting production,” Susee said. “With our program we can take information we gather with ultrasonic leak detection equipment detection equipment and provide a figure for how much money there is to be saved for each fixed leak based on the magnitude of the leak. Then, we can go ahead and fix the leak, or SCI can do it. It’s usually a no-brainer.”
Zorn Compressor & Equipment
Since 1965, Zorn Compressor & Equipment has developed a reputation as a leading provider of compressed air and vacuum solutions in the Midwest for customers ranging from printing plants and hospitals to dairies and manufacturers.
Zorn offers air compressors and vacuum pumps from high quality manufacturers, as well as custom turnkey installations, equipment service, parts, lubricants, rentals, and system audits. Its comprehensive product and service offerings, coupled with engineering expertise, results in compressed air solutions unique to each customer’s application.
The company prides itself on unparalleled service, backed by generations of industry leadership. It delivers a high level of service through its commitment to quality and by understanding customers’ applications with an emphasis on building strong personal relationships. At Zorn, air compressors are the company’s business and people are its focus, reinforcing its commitment to building strong relationships with customers, employees, and industry partners. It’s promise is quality, service, and expertise through leadership.
Headquartered in Pewaukee, Wisconsin, Zorn has branch facilities throughout Wisconsin, including the cities of Madison, Green Bay, Wausau, and Eau Claire. It also has facilities in North and South Chicago. Each branch offers the company’s full range of resources. For more, visit www.zornair.com.
Zorn Compressor & Equipment is a leading provider of compressed air and vacuum solutions in the Midwest. (Photo courtesy of Zorn Compressor & Equipment.)
Well Positioned for Growth
Today, the goal for SCI is to keep pace with increasing demand for its line of quality products. It’s an effort made easier since the company plans well ahead for the future, just as it has with the compressed air system at the Delavan plant.
“At the new plant, we designed and installed all of our systems like compressed air with quite a bit of excess capacity because we wanted them to take us through the next five years,” Bushman said, noting the plant is already adding two blow molding lines to the operation. “Right now, that five-year plan for growth is looking more like a 3.5-year plan, but that just means we’re growing a little faster than anticipated.”
The near term strategy for compressed air at the Delavan plant is to leverage the robust capacity of both air compressors before adding a third unit, but not before the completion of a thorough assessment. Bushman said the knowledge gained in specifying a compressed air system for the Delavan operation will be put to good use for years to come.
“Everything I learned in designing and building this production facility is going to help me out with the next one,” he said. “I’m sure there’s going to be a third one before too long.”
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