Look around. Do you see a piece of plastic near you?

You might be sitting on a plastic chair or holding a plastic pen. If you’re reading this online, your computer or mobile device has plastic components.Today’s proliferation of plastic is made possible through technology made by companies such as Technical Processing and Engineering Inc. in Lehighton, which builds and repairs continuous mixing and compounding equipment used in the production and recycling of plastic or rubber.Plastic is made primarily from oil and natural gas, but it’s a complicated process. Multiple steps are required to follow the “recipe” for plastic, and this recipe depends on what the manufacturer wants to do. Are they creating a light-free container for pharmaceuticals, a sturdy laundry detergent bottle, or a semiflexible container?“Think of wheat in the field, and think of oil in the ground. They bring the oil out of the ground. It’s a good commodity, but you can’t really use it. It’s the same with freshly harvested wheat,” said Harold Schafer, CEO of TPEI.He noted that for wheat to become useful, it must first be turned into flour. This can be equated to sending oil to a refinery. This flour must then be processed into bread or other foods, and baked before it can be consumed.“We take the wheat, so to speak, and send it to the baker. The baker adds salt and other things to create dough, which you can then bake,” Schafer said. “That’s what our customers do.”TPEI’s customers use their mixing machines to add their desired components such as UV stabilizers, anti-static, and color — or even the antimicrobial properties used in bread bags to prevent mold.The company currently produces one to five units per year, and more than half of their customer demand is for rebuilding and repair. They also have frequent requests for spare parts.“We have a very wide customer base, both international and domestic,” Schafer said. “These machines are highly specialized. Because of this, each new machine can take six months of design work and engineering.”The manufacturing floor has multiple continuous mixing machines, each in various states of repair or testing.Employees in a large machine shop complete the bulk of the company’s work, utilizing a combination of hand-operated and automated metal lathes and mills. Enormous steel blanks wait to be turned into replacement parts for extruders, and parts with an industrial hard finish (applied off site) awaited a final inspection and adjustments.A typical continuous mixing machine will combine all of the necessary ingredients after they are melted, then force the newly created polymers out using a high-pressure extruder.“The molten plastic will come out of the extruder in strings, like spaghetti,” said Slayton Altenburg, son of founder Slate Altenburg and the second generation to work for the company.These plastic strings are then put into a cooling bath and typically cut into pellets that will later be melted down to be molded into a final product. These pellets have the additional advantage of being cleaner than their original components, as coloring and dyes are typically lightweight and harder to contain.“It’s very dependent on what the customer wants, but we like to make our equipment capable of handling a wide variety of applications,” said Altenburg.Machines can be designed to process large or small batches of plastic, depending on need. If a company is using expensive materials or experimenting with color or properties, it’s critical that they can produce smaller batches to not waste material.Continuous mixers can also be used to recycle plastic, using heat to condense materials such as polystyrene (foam coffee cups) and remove gas and air.“Recycling is very costly. The more efficient the process, the more viable recycling becomes,” he said, noting that when a plastic water bottle is recycled, the cap, label and bottle itself are made of three different types of plastic that must be separated before melting.“We’ll work with companies to design a machine that grinds everything up,” then separates different types of plastic based on density or weight, said Altenburg.Each type of plastic can then be processed and extruded individually.It’s this ability to adapt equipment to a variety of needs that makes continuous mixers particularly valuable.“If you go to the grocery store and see Tide bottles, we know that equipment like ours was used to make the dye for that bottle,” he said. “You see these things in the world and know that we had a hand in that. We have a lot of pride in our work.”TPEI was founded in 1980 in Lehighton by Slate Altenburg. He previously worked in the continuous mixing industry for more than a decade, but was frustrated by the lack of availability for spare parts when machines broke down.“He couldn’t get spare parts for his machines, and got involved with the manufacturing process,” said Shafer.He soon learned that others in the business had the same problem, and that there were a large number of compounders looking for affordable access to quality spare parts.The business built its reputation on an ability to meet both long-term and emergency needs, and also sends employees on site to complete installations and repairs.“No matter where you are, 24 hours a day, you’re within a hand’s reach of a piece of plastic,” said Shafer.“It affects your life in every way.”