How frustrated would you be if you ordered a series of high-cost, custom-made baskets and the product you received didn’t work right for your process? What if your custom wire baskets let parts fall out during the wash, or allowed parts to clump together in a pile that keeps the parts in the center of the pile from getting clean?
Odds are that the production delays and excess scrap such poorly-designed baskets create would cause you severe frustration. Worse yet, these delays could end up putting you behind schedule on your own production.
Marlin Steel is frequently contacted by companies that thought they were getting a good deal on their previous baskets from a different vendor—at least until they actually tried to put those baskets to use.
Such was the case on a recent order for custom wire baskets for ultrasonic parts cleaning/degreasing.
The client had a highly specialized ultrasonic parts cleaning system that would rotate the baskets in the wash for maximum agitation and surface coverage of each part. Additionally, the smallest part in the wash process was a tiny 0.202” across, which would allow it to easily fall through the gaps between wires if they used the standard 0.25” gap for ultrasonic cleaning.
To add another layer of difficulty, at the midpoint of the client’s parts finishing process was a tumble blast cabinet which would expose both the basket and parts to severe abrasion.
This created a few opposing goals.
Normally, with ultrasonic cleaning, you want to minimize the amount of material between the ultrasonic transducer and the parts being cleaned—this means having more open space. Also, you want the wires to be a bit thicker so as to better withstand the stress of ultrasonic cavitation.
However, small parts mean that the spacing between wires HAS to be closer, or else parts will fall out. To minimize interference with the ultrasonic vibrations, each wire then has to be made a bit thinner.
The tumble blast cabinet would add even more stress to what the basket would have to endure. Once again, this would usually call for the use of thicker wires, but such wires could interfere with the finishing process.
Marlin to the Rescue!
When faced with creating a basket that could stand up to the sheer stress imposed by ultrasonic cleaning and tumble blasting for very small parts, Marlin’s manufacturing team didn’t give up.
Using advanced virtual physics simulation software, Marlin’s engineers could test all of their design variants quickly and thoroughly without having to waste labor and material on prototypes that wouldn’t work.
When a mesh size and spacing was identified as being suitable for holding the parts in place without interfering with the ultrasonic wash and tumble blast processes, Marlin’s engineers tested different types of metal alloys for the design.
The metal used here would need to be extremely resistant to corrosion while possessing a high tensile strength & hardness. After considering numerous grades of stainless steel, Marlin’s engineers settled on using grade 316L with a passivated finish.
316L Stainless Steel is the low-carbon variant of 316 which is more resistant to intergranular corrosion after welding or stress relieving processes. As a material, 316L is more resistant to corrosion from chloride exposure than grade 304 stainless steel, while maintaining high strength and impact resistance.
By passivating the alloy, the metal’s surface resistance to corrosion and pitting was enhanced. This would not only help the steel better survive immersion in ultrasonic cleaning fluids, it would help the basket survive the rigors of the tumble blast process.
Using virtual testing of basket designs and years of experience designing wire baskets for different parts finishing process, Marlin’s engineers were able to overcome the design challenges that had thwarted the client’s previous basket supplier.
Best of all, the client was able to get their new baskets quickly because they didn’t have to wait for real-world testing.