Efficiency is Green: Delta Manufacturing improves bottom line, environment

As with any good trailer builder, the leadership at Delta Manufacturing Inc. is always looking for ways to improve operations. And, Delta Vice President Les Eaves recognizes, a more efficient facility is also a more environmentally friendly one. The company’s efforts earned it this year’s Green Manufacturing Award from the National Association of Trailer Manufacturers.

“It’s a non-stop, ever-moving target, trying to be efficient,” Eaves explained to Trailer/Body BUILDERS in a plant tour highlighting the various improvements that earned the NATM honor. “You can’t have just yourself doing it; you’ve got to have some buy-in from your employees—and that can be very difficult at times.”

Delta, based in Newport, AR and about 60 miles north of Interstate 40 between Little Rock and Memphis, was founded by Dale Eaves, Les’s father, in 1971. Dale is still very actively involved in the day to day operations of the company. Les’s sister and her husband, Ami and Todd Norris, handle bookkeeping and quality control/production, respectively. The company now has about 70 employees who build “several thousand” trailers each year, a mix of horse and livestock trailers and equipment trailers: flatbeds, tilts, hydraulic dovetails, and dump beds.

In 2016, Delta began an expansion project that added 40,000 square feet to the manufacturing space, doubling its size. The company also worked with Entergy, the area utility, to evaluate the energy efficiency of the facility and make improvements, a “several hundred-thousand-dollar project,” Eaves noted.

Lighting upgrade

Delta’s factory had been illuminated with T12 lamps and metal halide lamps with magnetic ballasts “that used a ton of electricity.” These lights were replaced with a new, highly efficient, environmentally friendly LED system for the offices, the existing plant, and the new expansion area.

“Metal halide has got to be the least efficient lighting ever made—I don’t know why we put them in to begin with,” Eaves said. “When you move to the LEDs from the halides along with other efficiencies, you’re talking about saving over $3,000 a month—it’s unreal. There’s more light, it’s instant-on, at a fraction of the cost.”

The LED system also reduces other costs with fewer lamps and ballasts to be maintained and less lighting material to stock.

And the improvements, in addition to the bottom line, provide broader benefits: The new LED fixtures are environmentally friendly and comply with LEED standards, and the lower energy demand results in less stress on the power grid, meaning fewer pollutants from power generation plants.

At the same time, Delta replaced an old, leaky PVC pipe network with steel pipe to distribute compressed air throughout the building, and replaced the large, loud compressor with smaller, more efficient units.

“The pumps have to work about half as often to keep the system fully energized,” Eaves added.

Painting improvements

Delta switched its primer to a unique and proprietary PPG designed primer, which has a much longer “pot life.” This allows Delta to dramatically reduce the number of times that a primer flush is required. 

The overall cost savings per year just because of the reduced primer flushing (using less purge solvent, less wasted primer, reduced need for waste removal) is more than $50,000, according to Eaves. This also means that less primer is being wasted and requiring disposal.

The facility has also upgraded its paint system from manual to automated mixing. In the paint equipment room, “where the magic happens,” Eaves shows off the array of barrels containing the primer, paints, and urethane hardener, with hoses from each running to a central controller. He adds that the paint is not catalyzed until it reaches the mixing machine.

The new system replaced the previous “dumb” machines that simply pumped, whether the mix was correct or not; the new “smart” system can detect when there’s not sufficient hardener in the mix and sound an alarm.

“In the old days you used a pressure pot, and you had to mix up the color you needed and how much of that color,” Eaves explained. “Now we’ve got these valves: You just turn red off and turn gray on and start spraying. The only paint you waste is what’s in the line from the machine to the trailer.”

In addition to reduced paint waste, the system provides “cleaner, more efficient, better paint jobs.” And, Eaves notes, paint is a little less expensive to buy in 55-gallon drums. 

Delta also uses a proprietary system to reclaim waste paint thinner that can be reused for various applications through out the factory such as paint clean up, paint gun cleanup, etc. This reuse has reduced overall paint thinner purchases “dramatically.”  

“In the past, we purchased many drums of paint thinner that was primarily used for clean-up processes,” Eaves said. “The recycling program has also significantly reduced our need for waste thinner removal, which is expensive and not environmentally friendly.”

When the painting is done, Delta trailers now move into an upgraded, gas-fired bake oven.

“Heat is time. What used to take about six hours now only takes 30 minutes. It’s really hot,” Eaves said. 

The trailer is about 250 degrees when it comes out of the oven and takes about five to ten minutes to cool, then it’s “completely solid and dry.” 

“The beauty for us is if you have to take a trailer back to do any rework, you don’t have to wait a whole day or two to do it. It’s solid,” Eaves said. “You can sand a panel down and reshoot it, so we don’t have to send a trailer out that has any imperfections on it, that’s a good thing.”

High-efficiency wash systems

In the past, Delta utilized gas-fired pressure washing systems to generate the hot water needed to properly clean the all-steel trailers. During the factory expansion, Delta moved to new, highly efficient, electric on-demand water heaters.  

These heater systems don’t constantly heat the water as with the old systems. Instead, the new generation systems only heat the water as needed, resulting in significant gas energy savings when compared to the older systems.

Improved production processes

Improved production methods and improved outsourcing have resulted in significant scrap reduction.  Also, when scrap is generated, Delta’s varied product lines oftentimes can utilize scrap generated from one trailer line to another when usable and appropriate.

On the shop floor, the improvements include a new HYDMCH V-20 semi-automatic vertical band saw with the ability to miter from 60° left to 60° right. Its standard 4-degree forward approach angle provides increased efficiency in cutting of structural materials. The unit’s on-demand hydraulics combined with a constant torque electric feed control substantially reduces energy demand.

Delta also has outsourced parts fabrication to an area manufacturer that does precision laser cutting.

“We used to take a template, draw the pattern, and then hand-cut it,” Eaves said. “But if you tilt the plasma cutter ever so slightly it enlarges the hole and then the taillights would wiggle around in the hole. Now, with laser cut precision, that is no longer an issue.”

Additionally, Delta participates in a county-wide recycling program with all cardboard materials.

And Delta owns its own transportation department, with a fleet of five trucks, and organizes deliveries specifically to improve efficiencies with the goal of reducing fuel consumption.

“Freight’s a break-even scenario, at best, for us. We don’t make money on transportation,” Eaves said. “We try to keep the cost down for our dealers so we can sell more trailers.”

For a future improvement on the shop floor, Eaves said he hopes to automate the movement of trailers down the production line with an improved rail system. He’s also looking into purchasing a high-definition plasma or laser machine to start doing more parts cutting in-house.

Eaves also is looking into robotic welding cells for a couple of production stations that “could benefit greatly” from automation.