Stainless Steel vs Painted Steel Frame 1

[ksb24]

I am working on a custom, one off, welded frame design for a troughed roller conveyor. This will require a ~8'x2'x3' welded box frame (2" x1/16" thk square tubing) and two u channels about 6" wide, 2" tall, 6' long (9ga) welded on. Customer does not require stainless but painted steel at minimum. I primarily deal with stainless (pharma industry) as do all of my vendors so I would prefer sticking with it unless there is a big price difference between 304 stainless, painted steel, and galvanized steel . (I know I can just call up some vendors but they're all closed right now)

Thanks

 

[RVAmeche]

Are you asking if there is a big price difference? Yes, carbon steel will be much cheaper than the 304 SS you're used to.

 

[ksb24]

I'm aware of the cost difference with the raw material, but does getting a large frame like that powder coated eat up most of the cost difference?

 

[JohnRBaker]

I suspect that the stainless will still be more expensive.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[jlnsol]

Have made this comparison more than once and in every instant stainless was still more expensive.

 

[itsmoked]

And.... still a better route. Powder coating a BIG frame isn't cheap. Only select powder coaters will be able to do it. They often can be a pain to deal with as they don't have to compete on big items. They can more easily miss something on a big frame shape, then you have a problem with powder coating.

So what's your time and aggravation worth and multiple shippings. I suspect you can get a pretty good price on the stainless you normally use. Go with it and remind the customer they won't be having to scrape and paint the thing in a couple of years like they'd have to with a painted structure.

I'd guess the painting alone would be about $300 and change.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MJCronin]

Not true ....

"..remind the customer they won't be having to scrape and paint the thing in a couple of years like they'd have to with a painted structure"

Unless you are using WalMart paint ... and are located within 200 feet of the ocean ...

There are quality painting systems for carbon steel that will last for decades

Powder coating is not your only option ....

MJCronin
Sr. Process Engineer

 

[EdStainless]

A coating that may be of interest

https://www.uscoatings.com/blog/vsc...-coating-with-superior-long-term-performance/

I have seen this in action and it is very good.
Or you use a traditional system, blast white, Zn rich primer, epoxy, top coat

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[Unserviceable]

In my experience stainless steel has usually come in at a comparable price to mild steel blasted and painted to a high performance 3-layer paint system. Powdercoating is harder to comment on - it depends on what suppliers you have locally and what powders they are typically running. If it is likely that the frame will get dinged during installation, or will suffer scrapes or rough treatment in service, then stainless is an attractive option.

 

[MJCronin]

What is the problem with coming up with a conceptual sketch and getting budgetary quotes for painted and in stainless ???

We haven't even discussed schedule yet ...


MJCronin
Sr. Process Engineer

 

[CWB1]

Jersey tends to be expensive on pretty much everything, but here in the Midwest I'd figure a frame that size would be $50-100 to paint with a really good quality, UV-resistant industrial enamel and $150-200 to powder coat. Unless you're using uncertified scrapbinium stainless I'd be surprised if you could buy it for less than cheap carbon steel. Not sure of your requirements but one of the biggies with coatings and finishes is usually fading over time. If that's critical then you might find an industrial enamel is preferred as stainless can be a bear to keep bright and shiny, hence the clearcoats and waxes often applied to it.

 

[Nereth1]

My company designs these as a matter of course.

99% of our industry uses galvanised mild steel frames. Even sea ports use just plain galv. Only extreme places like salt mines or chemical plants might step it up to e.g. paint-over-galv, or pickled/passivated stainless.

For cost comparison, the entire frame you describe, assuming it weighs a hundred kg or so, isn't critically badly designed for fab, and we are selling at least a few dozen, would sell for ~a few hundred $AUD (and we are a high cost of production country), so there isn't room for expensive materials or treatments.

We can't understand the 1% of clients asking for paint alone. It is almost always (in our experience) more expensive and less effective then plain galv, and requires touchups after inevitable dings. Which, regardless of handling during install, it will get in service because of conveyed material spillage falling on it anyway.