Mining for Efficiency

Iowa Mold Tooling, Co., Inc. (Garner, Iowa) got its start in 1961 as a provider of tread designs for retreaded tires. Since then, it has evolved into a leading manufacturer of service vehicles and material handling systems, serving the tire, mining, construction, material handling, equipment dealer, railroad and utility markets around the world.

Today, IMT employs approximately 250 people and focuses its business on the mining and construction industries. Operating primarily through authorized dealers, the majority of IMT's business is in the U.S., with 10-15% of total business coming through the sale of exports.

Getting the Job Done

Among the types of equipment that IMT builds are articulating cranes, telescoping cranes, field service vehicles, mobile lubrication vehicles (which are used to haul and transfer water, fuel, oil, etc…) and tire handling vehicles and equipment. Because much of the equipment manufactured by IMT is used in the mining and construction industries, it must be able to operate in rugged terrains and be able to handle components and tires on these vehicles.

In the production of its truck bodies and material handling equipment, IMT works with structural steel, galvanneal and aluminum. All components on these vehicles can be manufactured entirely in-house, with the exception of vehicle chassis. Before painting, the structural steel is abrasive blasted and all materials are cleaned, pretreated and sealed with a multi-stage pretreatment process.

IMT’s facility features an automated paint line (provided by Therma-Tron-X, Inc.) for cranes and components and a manual paint booth for truck bodies. All parts are painted with Imron 5000®, a polyurethane enamel, supplied by DuPont. In addition to the two paint lines, IMT has three manual touch-up booths. Two of these are used for truck bodies, and a third is used for cranes. Although the Imron paint does not require baking, most parts pass through a baking oven to accelerate the curing process and aid in assembly.

Saving Money and Improving Performance

Several months ago, IMT began looking for ways to reduce operating costs without compromising product quality or worker safety. One area where the company observed a potential for cost-savings was the filters that it was using in its touch-up paint booths. For assistance with this endeavour, IMT approached Denny Threlkeld of Britt Enviro-Tech, a distributor for Columbus Industries, Inc. Mr. Threlkeld had previously assisted in the updating of IMT's weld smoke eliminator units, so both parties were confident that the performance of the paint booth filters could be improved upon, as well.

One of IMT's touch-up booths was using 48 two-inch pleated panel filters at the air intake supply. Though pleated filters offer extended surface area, they tend to face-load, limiting their service life. They also tend to be less efficient than self-sealing panels. Mr. Threlkeld advised IMT to replace the pleated filters with Columbus Industries’ SL-3A panel filter: a two-ply, high loft polyester filter with an external tackifier. The subsequent field tests yielded the results shown in Figure 1.

As a result of the additional service life realized from the move to the new filter, IMT forecasts an annual cost savings of $1,215 (assuming nine operating hours per week average) per booth (IMT's facility features seven booths, total). It is important to note that this estimation does not include cost reductions in change-out labor or disposal costs.

In order to ensure that the new filters are living up to expectations, the employees at IMT are diligent when it comes to keeping records about the performance of the filters. “You have to make sure that you have good ways of measuring results, both for your sake, and for the supplier’s,” said Steve Denny, IMT's Manufacturing Engineering Manager. “I think that was one of the good things about the way we went about this. We have a high degree of confidence that the information we’re gathering is good hard facts and something that will show up on the bottom line of the organization. It’s too easy to make some half-baked decisions about how much money we’re going to save and never really realize it. Too often you don’t go back and verify that it is truly doing you some good.”

Figure 1: Operating Cost Comparison Chart
Test A:	Test B:
The booth was set up to run as usual: Filters: 48 - 20" x 20" x 2" Pleated Framed Filters Cost: $5.99 each Total Cost: $287.52	New filters installed: Filters: 48 - 20"x 20" x 1 1/4" SL3A Self-sealing ring panels Cost: $2.99 each Total Cost: $143.52
Initial Readings: Manometer Reading: 0.48" WC Average Air Velocity: 192 FPM	Initial Readings: Manometer Reading: 0.40" WC Average Air Velocity: 193 FPM
Final Readings: Manometer Reading: 0.68" WC Average Air Velocity: 160 FPM Elapsed Time: 72.55 Hours Filter Cost Per Operating Hour = $3.96	Final Readings: Manometer Reading: 0.62" WC Average Air Velocity: 159 FPM Elapsed Time: 113.5 Hours Filter Cost per Operating Hour = $1.26
Benefits Brought by the Solution:
Cost reduction per operating hour = $2.70 Cost Reduction Percent = 68.18% Yearly Savings (assuming 9 operating hours per week average) = $1,215.00