One of the most common questions that Marlin’s engineers receive from clients goes a bit like this: “Will my wire baskets lose tensile strength if I get better corrosion resistance? And if so, is the tradeoff worth it?”
This question highlights one of the toughest challenges in creating custom wire forms—choosing the right material for the job.
When choosing a material for a custom parts washing basket (or any other custom metal form), you often have to perform a delicate balancing act. There are hundreds of different metal alloys on the market, each with different characteristics.
One alloy might provide better tensile strength, while another one might have better corrosion/temperature resistance. A third metal alloy might provide a much lower price point, but not be as strong or resistant as either of the other two options.
Why You Need to Consider More Than Just Cost
When considering a specific material for your manufacturing application, it’s vital that you consider not just the upfront cost, but how the performance variables will impact useful life and utility.
The upfront cost of a material for your basket is important, but it should rarely be the sole driving factor behind your decision. Just because one material is cheaper per pound doesn’t mean it will be less expensive over time.
A material that’s lacking in tensile strength or corrosion resistance well below the stresses of your production process is much more likely to break after only a few uses.
For example, say an order of baskets for a wash process using corrosive chemicals would cost $4,000 if made with plain steel and $8,000 if made with stainless steel that has much better corrosion resistance. For argument’s sake, say the non-resistant baskets would last 1.5 years before becoming too corroded to be useful, and the resistant baskets would last 9 years.
Over the lifetime of the $8,000 basket order, your company would spend $24,000 on the “cheaper,” non-resistant baskets. That’s a total cost of ownership of three times more for the basket with the lower upfront cost.
Balancing the Characteristics of a Material with Your Production Process
Of course, total useful life isn’t the only consideration that needs to be made. Different production processes will place different stresses on a basket—and a few manufacturers will need to put their products through several vastly different processes.
For example, heat treatment and ultrasonic parts washing are two processes that place very different kinds of stress on the parts and baskets being run through them. The temperature extremes of a heat treat cycle often demand high temperature tolerances and resistance to scaling while the chemicals and vibrations used in ultrasonic processes might demand greater corrosion resistance and durability.
One compromise is to use two different baskets. However, this adds time and labor for swapping parts from one basket to another in between processes. Using a single basket made with a material that’s resistant to both scaling from heat and corrosion from submersion in chemicals would be more efficient in the long term.
However, there’s always a trade-off. High-performing alloys that boast high strength and resistance to different stress factors tend to be costlier. In some cases, there may not be a readily-available alloy that would provide optimal performance for all stages of your production process.
On the other hand, you might find several alloys that closely match or exceed your performance needs. When this happens, carefully balance the specific characteristics of each to find the one that would give you the best utility and total cost of ownership over time.
When looking for a basket material for your particular production process, be sure to check the performance characteristics of many different metal alloys to ensure that you find the best material for the job.
Here, having the opinion of an experienced mechanical engineer might be of some help.
Ultimately, your basket material choice is just that—your choice. However, picking the right basket material goes a long way towards making sure that you get the best possible return on your investment.