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Optimum Precision, Inc.
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Polyurethane Parts Company Puts Quality Above All Else

Various parts for the paper and box industry by Optimum Precision. The company uses a mix of chemistry and system controls to ensure top-notch quality of its parts.
Photo courtesy Optimum Precision

Rebecca Carnes
Design-2-Part Magazine

In Ken Christiano's world of polyurethane parts, consistency is the key to quality and quality rules supreme. As president of Optimum Precision, Inc., Christiano, with 30 years of polyurethane experience, knows that above all else, his customers want a part they can put into their machine and know it will work without failure.

They don't have the time or money to worry about replacing a polyurethane part before its time is due, and they simply expect it to work all the time, every time. Christiano's customers primarily use polyurethane parts in equipment that's part of manufacturing processes, so the part is usually a wear item that needs to stand up to a heavy brunt of the work.

"Most of our customers are doing a manufacturing process or have equipment that needs to be working all of the time. These people don't want to be concerned about a polyurethane part not doing its job. They want to be concerned about the logistics or the bigger picture, not so much how their processes are being done," Christiano said. "They want to take it for granted that it's (part) going to be working. They want to know they can use this part and not have to worry about it for three months."

Heavy Dose of Chemistry

With extensive past experience working in manufacturing as a production engineer, a process engineer, a manufacturing manager, and then a principal applications chemist for the polyurethane group of a major chemical company, Christiano also has a degree in chemistry with a concentration in chemical engineering. He brings a vast amount of knowledge of the inner workings of polyurethane production so that he is able to narrow the processing windows and tightly control quality through the manipulation of chemical processes.

"Through our years of experience and expertise, we're able to narrow those windows even more to guarantee even better consistency," he said. "Through the work in the lab and looking at different process conditions, we've narrowed the window down from what the vendor gives us—saying these properties can vary as much as 20 percent. And we'll take it in and, through our pro­cess, we can hone that (window) into plus or minus five percent, and that gives you a better consistency to our end product and our customer's."

Christiano has been with Optimum for about 12 years and, with his experienced staff, can narrow the range for physical properties, tailoring them based on their extensive knowledge, he said. They can boost up the tear strength while maintaining the hardness, increase the coefficient of friction while maintaining the same hardness, or reduce it based on what the end applica­tion is. Most customers don't realize the extent of tinkering with chemistry that goes into producing a top-notch part.

"The customers don't care about the little details and what the physical properties are; their ultimate concern is they want a part that lasts," Christiano said.

The tweaking process goes beyond the hardness scale by fac­toring in aspects like abrasion and tear resistance of a particular material. "I could go ahead and, through the recommended process window, I could make five pieces that are all the same 85-A hardness, but of those five pieces, I could have tear strengths that vary as much as 15-20 percent from the low to high end because that's a little piece of the puzzle," he said.

All in the End

Keeping the end use in mind is important when formulat­ing the product. It affects the process windows that result in a consistent product in whatever application it is needed. As with a polyurethane wheel that goes into a paper-feeding or money-counting machine, the hardness might be the same for a set of similar products, but the coefficient of friction might need to be different, depending on the end use.  An ATM machine outside in the Northeast and one outside in California have different dimensional stabilities that should affect the manufacture of the polyurethane part that goes into the machine.

Various parts for the bottling industry by Optimum Precision. Based on a part's end application, Optimum Precision can boost the tear strength and increase or decrease the coefficient of friction.
Photo courtesy Optimum Precision

"A temperature difference can give you different expansion of the particular parts inside that would create variances in the way that their product worked. It wouldn't count the money correctly," Christiano said of one customer that came to him for help. "In that instance, we were able to change the coefficient of friction."

If a customer comes to Christiano and asks for a part of a certain hardness and color and that's it, he tries to talk to them more about what it will be used for.  He wants to know a number of things. What is the end application? What is the particular mode of failure? Is this part, when it's finally done, getting replaced because it's broken apart, worn down, or because it's the same dimension, but just not doing the job anymore?

"And then we can tweak and optimize the formulation for a specific application," he said. "That's why we try and work with our customers. We try and partner with them and say, 'If it's a wear item, let's give you the best formulations so you can maxi­mize the life of this product so that it ultimately saves you money with replacement parts cost and there's less down time with your equipment because if your machine is down, you're not using it to make money."

Having worked as a chemist in the past, Christiano has ex­perience setting up experiments to specifically look at different physical properties. He used to travel to companies like Optimum Precision and troubleshoot their process to optimize it.

Optimum Precision (www.optimumprecision.net), a wholly-owned subsidiary of Precision Escalator in Kenilworth, New Jersey, is a small company and operates without a large lab. "But I have good people that work for me in the manufacturing process, and. if I need to test something out, I work up the formulation. I still go out and do that myself sometimes—then I give it to a couple of my people and say 'This is the formulation I want, so go ahead and make this part for me and we can get it tested,'" he said.

Above and Beyond

Being a small company allows Optimum Precision to make a decision and move forward on a project more rapidly, but also regulate heavily for quality control. Going beyond vendor certificate analysis reports for incoming raw materials, Optimum Precision will always sample the material first before it goes into production.

"Before putting it into our process machine, we'll actually do a hand batch mixture of the material to make sure that it processes within the same parameters that we expect it to. Not everybody does that, but it's an extra step we do to ensure what it is before we put it into our process," he said. "I've had a few hiccups in the past 30 years of business where I've gotten material in and we did a test of it and it didn't give us what we were looking for, and it was a problem. And so we had to put a particular lot off to the side and found out that in the vendor's process, they traced it back and that particular material saw a little bit extra heat in their process because they had a valve that broke, and so it stayed in their tanks a bit longer."

The company also randomly takes finished parts and does tests such as destructive testing. They will sometimes run a part on a machine until failure. "We'll keep increasing the load until it fails, and that value becomes a reference point correlating back to the chemical process," Christiano said, adding that getting the chemistry right is what leads to quality.

And maintaining that quality means a longer lasting part for customers.

Various parts for the automotive industry by Optimum Precision. Maintaining quality means a longer lasting part for customers.
Photo courtesy Optimum Precision

"It's about maintaining that consistency because even though the customer is not seeing any variability in the part that we're supplying them,we're reducing the process variability for ourselves in-house, which, ultimately, could provide some of the little physical properties that extend the part life. It's all about continually improving and tightening your process controls," he said.

No Place Like Home

After heading overseas for lower prices in past years, Chris­tiano said he has customers heading back to him for work, mostly due to quality. If you're replacing parts too often, you're not sav­ing money in the long run, Christiano explained.

"Some customers have said, 'I've got someone else that gave me this part for 50 percent less (overseas) and I'm going to them.' And a lot of times in their particular process, they might not realize it, but sometimes a year and a half down the road, that same guy comes back to us and says, 'After using that guy's product for a year, we're spending five percent more money in replacing parts,'" Christiano said, adding that the down-time associated with changing parts is another factor.

Optimum Precision had some OEM customers who went off­shore for pricing differences, but a lot of them no longer make the volume of new equipment like they used to, so some have taken on a maintenance role where they're refurbishing and upgrading other companies' equipment along with their older equipment.

"In order to do that, they need to locally source replacement parts for those items, and, in doing so, have found that our quality is excellent, our rates are competitive, and so now we're starting to supply their new parts also," he said.

And because they're now servicing different types of equip­ment, they need a full container of not just one particular part, but 20 or 30 different parts, which is not conducive to doing business overseas. And quality still comes into play.

"After waiting eight weeks and you finally receive your product from overseas and there's a problem, it just can't be resolved the next day. So a lot of those customers that have time-sensitive deliveries and quality issues are now sourcing locally because if there's an issue that comes up, we can take an hour drive or short flight and go visit the vendor and resolve it," he said.

Christiano said there's a simple reason why quality is of upmost importance to his company.

"A lot of times in testing and development, it takes you years to develop a relationship with a customer and to develop their trust and supply them with a consistent product," he said. "But it only takes one time to make a mistake and they get a product that fails in half the time. And all of a sudden, they don't remember the eight years of consistency you gave them; it's the one time that you cost them money — that down time. They'll remember that. That's what sticks in people's heads".