Liquid Coating for Automotive Industry

An ideal solution for one manufacturer serving the automotive industry was the Nordson OptiMix™ 1 plural component liquid metering system, used in conjunction with the Trilogy® manual electrostatic spray gun.

“Ground Effects, LLC, based in Windsor, Ontario, Canada and (www.gfxltd.com) founded in 1986, is a supplier of interior and exterior accessories to the automotive industry.

The company produces a wide range of automotive parts and offers mass vehicle customization and surface coating services, such as e-coat and powder coatings, hydra graphics and polyurea spray coating. In order to serve a key customer, Ground Effects opened a new facility in Westlake, Ohio, USA, in January 2015.

The customer relies on Ground Effects to apply a specialized rust inhibiting coating to super duty vehicles and related parts. The facility houses two robotic coat[1]ing lines and one manual coating line.

Initially, when the company installed its first plural component system on all three of its coating lines, things got off to a rocky start. The rust-inhibiting coating material is a 5:1 ratio resin to catalyst mix. The catalyst, which accelerates curing time, is quite aggressive and causes the mixed material to have a very short, 15-minute pot life.

The old system mixed the resin and the catalyst materials in a remote manifold that was dragged across the floor by the painters. The materials travelled by two separate supply lines to a special manifold, followed by a 6-foot (1.8 m) dispensing hose from the manifold to the spray guns.

The mixed materials would begin to harden while in the manifold and in the spray guns. “That’s where the failure was – you cannot spray coating material when it has hardened and blocked the lines,” says Schwamberger.

By contrast, the Nordson system mixes resin and catalyst in the OptiMix unit right at the spray booth wall and delivers the mixed material via low friction fluid line to the spray gun. The purge process uses a small amount of solvent in conjunction with a large quantity of compressed air to flush the paint line, referred to as air chop.

To minimize the amount of solvent used during flushing, Nordson replaced two individual 50’ (16m) feed lines, one for catalyst and one for resin, and a 6-foot (1.8 m) mixed fluid line with a smaller diameter 35-foot (11 m) mixed fluid line with an integrated, variable, air chop.

The air chop introduces compressed air and solvent into the fluid line at the same time, creating a scrubbing action within the system. This process greatly reduces the accumulation of cured coating on the interior of the paint lines.

Since permanently installing the OptiMix 1 plural component system and Trilogy spray guns, Ground Effects has eliminated the maintenance costs and downtime they experienced with the previous, competitive system.

They also increased paint transfer efficiency by about 20% versus the old turbine style electrostatic spray guns. The Ground Effects team does preventative maintenance every-other week, rather than required maintenance every-other day on their previous system.

They no longer spend time troubleshooting, experiencing downtime or buying rebuild kits. With Nordson, they replace the static mixer, every couple of weeks at about $20 each, instead of $400 to $500 of downtime every few days with the old system.

Nordson installed the equipment and stayed at Ground Effects for over a week to work with their paint operators to ensure they understood the system’s capabilities and were comfortable running the system on their own.

The savings have been so substantial in the manual booth that a second booth with two robots has now been converted from the original metering systems and turbine style, electrostatic spray guns to the Nordson OptiMix 1 paint metering system and RA-20R robot mounted rotary atomizers.

The RA-20R provides superior atomization. The fine paint particle size, combined with Nordson’s special shaping air kit provides exceptional penetration into recesses and Farady cage areas.

This provides high transfer efficiency and uniform coverage on these difficult to paint parts. This system has been in production since the beginning of the year and allows Ground Effects to continue enjoying the benefits of Nordson Liquid Systems technology.