Pretreatment Helps Nailor Industries Hammer Home Better Finishes
A change in its pretreatment system helps manufacturer get better coating adhesion.
First impressions are everything when it comes to surface finishing and Adam Bick from Nailor Industries knew right away that a change in its pretreatment was going to work out just fine.
“It was instant,” says Bick, paint division manager for the Houston, Texas, manufacturer of commercial and industrial HVAC products. “The minute we turned our electrocoat system back on, we knew we were getting better adhesion and better film build. It was obvious.”
While the end result was a huge success for Bick and his team at Nailor, it wasn’t always an easy path to get to coating heaven. Starts and stops with vendors and suppliers, while searching for the right combination of chemicals and systems, proved daunting at times, but the culmination was more than satisfying.
With over 450,000 square feet a month that needs to be ecoated, the task to find a pretreatment system that worked properly was paramount to Bick. He was brought in three years ago by Nailor to revitalize an ecoat line that had sat dormant for almost seven years. The company was wanting to move away from powder coat to a more economical ecoat system and, even though they had purchased a used ecoat line 10 years earlier, they did not decide to relaunch the line until bringing in Bick in 2016.
“There were several other attempts before I got here to get the line up and going, but it never did work well for them,” says Bick, who previously ran an ecoat line for Metalsa in Kentucky before joining Nailor. “They had several different suppliers in and all of them seemed to have trouble getting it going correctly. And a lot had to do with getting the pretreatment working like it needed to be.”
Air Control and Distribution Products
Nailor manufactures over 1,200 different air control and distribution products, including variable air volume terminal units, fan coil units, electric duct heaters, sound attenuators, air handling units and filter housings. The company has 11 manufacturing facilities, totaling over 850,000 square feet, located in three countries. In addition to Nailor Industries, it also operates under business names such as Engineered Comfort, Thermal Corporation, Klean Aire, Advanced Air, Engineered Acoustics and Manufactured Air Products.
Bick was working with Bulk Chemicals (BCI) for the powder coating system that Nailor still has in place as it tried to work everything over to ecoat, and asked BCI’s Scott Felien to take a look at the 5-stage pretreatment line to recommend a solution.
“They just weren’t getting the results that they were hoping for,” Felien says. “We had worked with them on some of their other facilities, and we had a very good idea of what type of results they were looking to get. Once we started working with them and producing some parts, it was obvious there was a difference in the results.”
Bick says it was more than obvious. “It was night and day.”
BCI’s zirconium pretreatment package has several additives built into the process that seemed to make a difference on the ecoated parts, Felien says.
“They went from about a 40% reject rate to maybe less than 1%, if any,” he says. “I think the reality was that we are a true pretreatment company and this is something that we specialize in. Other vendors may have brought in their own pretreatment system, but it obviously wasn’t working out for them.”
Chromium and Phosphate Free
Felien and BCI’s John Anderson went to work on getting the system converted over to the Zirca-Sil 18 process, which is a chromium and phosphate-free liquid chemical used to produce a paint bonding and corrosion-resistant surface treatment on aluminum, zinc, ferrous and other metal surfaces prior to painting. It is often a replacement for iron and zinc-phosphate chemistries, and is a homogeneous inorganic conversion coating based on the formation of a layer of nanometallic matrices of compounds.
The new pretreatment process starts with a cleaning and water rinse before heading into the third stage of Zirca-Sil 18 and water rinse, which could include an optional additive. The fourth stage is Zirca-Sil 18 again, followed by a water rinse in the final stage, although there could be an optional sealer as well.
“They actually don’t use that much chemistry at all,” Felien says. “But Nailor is getting extremely high performance out of this system.”
Because ecoat often cannot hide flaws in the coating — whereas a powder coat at three to four mils can do that on a part — it needs to perform at a very high level in order to avoid rejection.
“You have to get the ecoat looking uniform and without any streaks or it will telegraph all of those defects,” Felien says. “Nailor also performs a lot of best practices, which includes keeping up with the titrations several times a day. We only request it twice a shift, but they have a great laboratory and do a lot of maintenance on the washer, and that just makes things work so much better.”
From start to finish, Bick says it took about six months to test the parts in the pretreatment system with BCI until they switched over the system, but even then it took all of 24 hours to get the old chemicals and system out and the new one in place.
“The results were immediate,” he says. “Since we’ve had it running for a while now, we’ve even started to see that this pretreatment system is cheaper than before.”
Bick says that when previous parts were inspected and found with adhesion problems, the entire lot of parts were scrapped. The current system has cut down on those scrap costs and further made a return on investment with the switchover. He says there are several lessons learned in this process.
“Talk to different chemical companies as soon as you have problems,” he says.
Visit Nailor.com and bulkchemicals.us.
Better adhesion, enhanced corrosion and blister resistance, and reduced coating-part interactions make pretreatment a must.
A review of available test methods, common applications and innovative instrumentation...
Types of phosphate conversion coatings, how to apply them, and their specific functions.