Galvanized and Galvanneal · Miami Gardens, Florida
Galvanized and Galvanneal Fabrication
Zinc-coated steel for parts that live outdoors or get painted. We laser cut, punch, form, weld and finish G60 and G90 galvanized and galvanneal sheet for enclosures, panels, brackets and equipment housings, prototype through production.
Overview
Corrosion Protection Without the Cost of Stainless
South Florida is one of the most corrosive climates in the country: humidity, heat and salt air. Zinc-coated steel gives outdoor enclosures, electrical boxes, HVAC parts and equipment panels years of protection at a fraction of the price of stainless steel.
Galvanized and galvanneal are two of the materials customers ask us for most. MJM fabricates both under one AS9100 Rev D and ISO 9001:2015 quality system. For cutting detail see galvanized steel laser cutting.
Which One
Galvanized vs Galvanneal
| Material | What It Is and When to Use It |
|---|---|
| Galvanized (G60, G90) | Steel with a pure zinc coating and the familiar bright spangle. G90 carries more zinc than G60. Best for parts used bare: outdoor boxes, back panels, HVAC housings, brackets and hangers. |
| Galvanneal | Galvanized sheet that is annealed so the coating becomes a matte gray zinc-iron alloy. It takes paint and powder coat very well, spot welds and forms cleanly, and still protects the steel at a scratch. Best for painted or powder coated enclosures and cabinets. |
Rule of thumb: if the part will be powder coated or painted, ask for galvanneal. If it stays bare, ask for galvanized. Put the coating designation on the drawing.
Processes
How We Fabricate Zinc-Coated Steel
Five amada lasers (one ventis 4 kw fiber, three ensis 3 kw fiber and one co2) on 5 x 10 ft tables, with fume extraction for zinc. The coating burns off in a narrow strip at the cut line; the rest of the sheet stays protected. Tolerance ±0.005 in.
Punching shears the sheet cold, so the zinc is not burned at the edge. The Amada AE 2610NT also forms louvers and knockouts for outdoor boxes. CNC punching.
Nine Amada press brakes to 240 tons and 14 ft. Forming.
Resistance spot welding, MIG and TIG with proper ventilation for zinc fumes. Welded areas are cleaned and touched up or coated. Welding services.
Self-clinching nuts, studs and standoffs installed on four Haeger presses. Hardware insertion.
Powder coat and paint over galvanneal, zinc-rich touch-up at cut edges and welds when called for, and laser marking. Finishing.
What We Build
Galvanized and Galvanneal Parts
- Outdoor electrical enclosures: Type 3R style boxes, meter and panel housings, back panels and subpanels. See electrical enclosure fabrication.
- Painted cabinets and housings: galvanneal cabinets, doors and covers for kiosks, security and access control, telecom and data center equipment.
- HVAC and refrigeration: housings, panels, brackets and ducts.
- Construction and transit: brackets, clips, hangers and equipment mounts.
- Marine and coastal equipment where bare carbon steel would rust in a season. See marine fabrication.
Design Notes
Design Tips for Zinc-Coated Parts
- Cut edges are bare steel. For most parts the surrounding zinc protects the edge. Where it matters, call out zinc-rich touch-up or a full powder coat.
- Minimize welding. Welds burn away zinc. Tabs, formed corners, spot welds and hardware keep more of the coating intact.
- Specify the coating weight (G60, G90, or the galvanneal designation) and whether the part is painted.
- For harsher exposure such as direct salt spray or washdown, consider stainless steel or aluminum.
Straight Talk
What We Do Not Do
We fabricate from pre-coated galvanized and galvanneal sheet. We do not hot-dip galvanize in our building; weldments that need hot-dip galvanizing after fabrication are quoted with that step included.
FAQ
Galvanized and Galvanneal Questions
What is the difference between galvanized and galvanneal steel?
Galvanized steel has a pure zinc coating with a bright spangled surface and is normally used bare. Galvanneal is galvanized sheet that has been annealed so the coating becomes a matte zinc-iron alloy, which holds paint and powder coat much better and spot welds well.
Does MJM fabricate galvanized and galvanneal sheet metal?
Yes. MJM laser cuts, punches, forms, welds and finishes G60 and G90 galvanized and galvanneal steel at its Miami Gardens, Florida facility.
What happens to the zinc coating when galvanized steel is laser cut?
The zinc burns off in a narrow strip at the cut edge, leaving bare steel at the edge while the rest of the coating stays intact. Edges can be touched up with zinc-rich coating or covered by powder coat when required.
Should I use galvanneal for powder coated parts?
Usually yes. Galvanneal gives paint and powder coat a better surface to bond to than bare cold rolled or spangled galvanized steel, and it keeps protecting the steel if the coating is scratched.
Can MJM weld galvanized steel?
Yes. MJM welds and spot welds galvanized and galvanneal steel with proper ventilation for zinc fumes, then cleans and protects the welded areas.
What is G90 galvanized steel?
G90 is a coating designation meaning a total of 0.90 ounces of zinc per square foot of sheet, counting both sides. It is the standard commercial coating for outdoor sheet metal parts. G60 is a lighter coating.
Related
Related Services
- Galvanized Steel Laser Cutting: G60 and G90, what happens at the cut edge.
- Steel Fabrication: cold rolled and hot rolled sheet and plate to 1 in.
- Electrical Enclosure Fabrication: NEMA-type boxes, cabinets and panels built to print.
- Stainless Steel Fabrication: 304 and 316 cut, formed, welded and finished.
- CNC Punching Services: Amada turret punching with 794 tools on the shelf.
- Metal Finishing and Powder Coating: powder coat, anodize, chem film, passivation and plating on one PO.
- Custom Metal Fabrication: the full shop under one roof.
Send Us Your Drawings
STEP files and PDF drawings to sales@mjmmfg.com or (305) 620-2020. Quotes in 24 to 48 hours.