Coachmen Industries Makes Significant Cost Reductions

ALGOR SOFTWARE HELPS COACHMEN INDUSTRIES MAKE SIGNIFICANT COST REDUCTIONS

The popular, pull-out "room" can be seen in this photo. The bracket supports virtually the entire weight of the slide-out unit as it is being deployed or brought in.

Creative engineering, combined with high-accuracy analysis, reduces material costs by more than 60%, labor by 78%.

Overview of Results:

Cost: Reduced 61%

Weight: Reduced 36%

Pieces: Reduced from 4 to 1 (75%)

Labor: Bolts reduced from 9 to 3 (66%)
Holes reduced from 12 to 1 (92%)
Average labor reduced by 78.8%
Strength: Unchanged

There are many ways companies become leaders in their respective industries. Coachmen Industries has become a leader in the recreational vehicle, motor home and travel trailer industry through a commitment to quality and value that is based on excellence in engineering and attention to detail.

Coachmen has kept pace with computer-aided design hardware and software technology in an effort to create the best possible products. Engineers at Coachmen began using computer-aided design on desktop computers almost a decade ago. In recent years, their use of high-accuracy Algor analysis software has increased because it has proven to be a cost-effective and productive way to optimize component designs.

A recent internal company report by Project Engineer Jim Keough provides an example of the degree of cost reductions that are possible when creative engineering and teamwork are combined with Algor design and analysis software technology. The report documents the re-design of a single component, in this case a slide out bracket used in a "fifth wheel" travel trailer option.

Coachmen Industries Project Engineer Jim Keough with the final bracket design.

Adding Room

The bracket is part of an assembly that allows an additional "room" to be extended from the side of the trailer, which is manufactured by Shasta Industries, a Coachmen division. The feature is becoming very popular with Shasta customers because it adds considerably to the livability and available space in the trailer without increasing its size when being towed. The bracket assembly is critical to the operation of the device because it supports virtually the full weight of the "room" while it is being either extended or pulled back.

Shasta engineers were developing alternative bracket designs in an effort to make the part less costly and easier to install without reducing its structural integrity. The engineers realized they could save time, effort and money by teaming up with Mr. Keough and using Algor software to analyze alternative designs.

"Dialing-in" Design Solution

"The advantage of using Algor software," said Mr. Keough, "is that a number of prototypes can be tested and evaluated without taking the time and money to make prints, send out for quotes, order prototype parts and test, only to find out that the part must be re-designed. Algor software allows the engineer to dial-in on the proper, cost-effective solution to the design problem without even making a part. The product must still be evaluated, but the development phase is primarily accomplished on the computer.

A Better, Less Costly Part

Mr. Keough's internal report features Algor analysis results for four proposed prototype designs (see accompanying photos). By the time the engineers arrived at the final design, they had achieved an outstanding level of material and labor savings while retaining the part's original suitability for the job. "The original design," said Mr. Keough, "included four parts weighed 13 pounds, 15 ounces, used nine slots and twelve holes. It required multiple shearing and forming processes to produce, thereby driving up the costs.

"The final bracket includes two formed parts and one section of structural tube," continued Mr. Keough, "The number of holes has been reduced to four and the weight is only 8 pounds, 14 ounces. The unit price has been reduced by 61%, weight is down 36% and the average amount of labor required for installation is down 78%. I'd call that a successful re-design.

So would we, Mr. Keough. So would we.

Step-by-Step:
How Coachmen and Shasta reduced the cost of the sliding bracket

1) The Original Design
The original unit includes four parts and weighs in at 13 lbs, 15 oz. Multiple shearing and forming processes are necessary to manufacture the unit. Manufacturing costs are further inflated by the use of nine slots and ten holes. The bracket is also very difficult to install. A prototype showed, however, that the bracket performed well and was easily able to survive its working environment.

2) FEA Model Number 1
The first re-design reduced costs, but there were questions about structural integrity. Shasta engineers worked with Jim Keough to develop a model for high-accuracy Algor analysis. A stress contour showed that this design would fail at the bend adjacent to the slide-out floor. Also, the analysis indicated that the upper two-thirds of the bracket and the angle reinforcement on the lower half were not needed.

3) FEA Model Number 2
Based on the results of the first Algor analysis, plates were added to the side in an attempt to reduce the bending forces on the angle section. Also, the unstressed material was removed which allowed for the elimination of two slots. This time, however, the Algor analysis showed high bending stress at the same location as Model 1. It was time to re-think the basic concept.
4) The Final Design
A web section was added and the overall design was changed substantially. The entire design consists of two formed parts and one section of structural tube. Algor high-accuracy analysis showed acceptable levels of bending stress in the problem area. The new bracket assembly costs less, its easier to produce and install, uses less material, weighs considerably less and works just as well as the original design.