Corrosion-resistant joints for sheet steel structure 1

[CalculatorDave]

Hello all,

My question concerns "design for corrosion resistance" and "design for automation". Specifically, the design of fast, corrosion-resistant joints for a sheet steel structure.

Our material is pre-galvanized sheet steel. Our current joining method is clinching - this process has the advantage of (1) not damaging the galvanizing layer and (2) not requiring precise hole alignment (no holes at all). However, the cycle time (about 1 second) is relatively slow. Also, the clinching process doesn´t seem well suited to automation in our case.

Self-piercing rivets have a too-slow cycle time (also about 1 second). Blind rivets require precise hole alignment.

Spot welding seems to be the fastest joining process for sheet metal. However, the heat will vaporize the zinc around the weld region, and re-coating these regions (with a cold galvanizing coating) is not an option. We COULD choose a different material- I´ve already considered aluminum (not stiff enough) and stainless steel (too expensive). We´ve already re-designed the structure to reduce the number of joints.

Any thoughts on a corrosion-resistant, automatable joining process for this sheet metal structure?

Thank you,

SD

 

[IFRs]

You have an optimim method of joining that eliminates several costly steps and results in a better product. I would work on finding a way to "clinch" faster. Does your company have a web site or can you send me some drawings?

 

[arto]

how about adhesive??

 

[CalculatorDave]

Adhesive could work if it had the following properties:

1. Service temperature up to 100 deg. C
2. Fast setting time (10 minutes or less)
3. Excellent strength and toughness
4. Moisture-proof

For our particular structure, I think that clinching would be faster than adhesives. Unfortunately .

SD

 

[IFRs]

Acrylic and Methacrylate adhesives may work for you.
3M makes acrylic tape adhesive. Instant stick.
Look on

http://www.devcon.com

for Metal Welder - the stuff is amazing. Cures fast also.