Metal enclosures guard electrical, mechanical, and technological components. Protection is the name of the game when it comes to these enclosures, which range from simple boxes to complicated multi-level assemblies. If you’re new to the metal enclosure industry, this beginners’ guide will help you understand the basics.  

Common Metals Used for Enclosures  

Your metal choice is critical to ensuring your enclosure will meet your expectations around durability, weight and protective properties (i.e., heat and corrosion) 

Here are some of the commonly used metals for enclosures:

1. Aluminum: Lightweight and naturally corrosion-resistant, aluminum is an excellent choice for outdoor enclosures. It’s easy to work with, strong for its weight, and holds up well in tough conditions. 
   
   
2. Stainless Steel: If strength and durability in harsh environments are a priority, stainless steel is a solid option. It resists corrosion exceptionally well, making it ideal for applications exposed to moisture, chemicals, or extreme temperatures.
   
   
3. Cold-Rolled Steel (CRS): A cost-effective and durable material, CRS is commonly used in enclosures that require strength and precision. However, it does need a protective coating—like powder coating or plating—to prevent rust over time.
   
   
4. Hot Rolled Pickled and Oiled (HRPO): HRPO steel undergoes a process that removes surface impurities and applies a protective oil coating, making it more formable and durable than standard hot-rolled steel. It’s a great fit for industrial enclosures and structural applications that need a balance of strength and workability.
   
   
5. Galvanized Steel (G90): G90 steel is coated in zinc to help prevent rust and corrosion, making it a reliable choice for enclosures that need protection from moisture, especially in moderate outdoor environments.

Now that we’ve covered common metals, let’s dive into the fabrication process.

An Overview of Metal Enclosure Fabrication  

Here are some commonly used steps in fabricating metal enclosures to ensure they meet the required standards and specifications.  

Engineering 

All fabrication processes begin with engineering and design. This includes defining the required features, dimensions, material, and tolerances. Engineers create detailed models that are the blueprint for the enclosure build. To ensure that enclosures are engineered to best fit their production requirements, engineers review DFM (Design for Manufacturing) possibilities to see if there are opportunities to improve the design for manufacturing processes, reducing cost and improving efficiency. 

Metal Cutting  

Once the design is frozen, the metal is precisely cut into flat patterns using laser cutting, turret punching, or waterjet cutting. These advanced cutting methods ensure accuracy while reducing material waste and maintaining high-quality edges. 

Metal Bending & Forming 

After cutting, the metal sheets are shaped into the required enclosure form using press brakes or panel benders. Maintaining tight tolerances during this process is critical to ensure proper fit and function, especially for complex enclosures with multiple bends and intricate features. 

Welding & Joining  

For enclosures that require assembly, TIG, MIG, or spot welding fuse metal components together, ensuring structural integrity and strength. Depending on the application and material compatibility, riveting or fasteners may be used instead of welding in some designs. Clean, precise welds are essential to maintaining durability, aesthetics, and functionality. 

Assembly (Including hardware insertion) 

Once the enclosure components are fabricated, assembly ensures structural integrity and functionality. Fasteners such as PEM inserts, standoffs, and hinges are installed to support mounting and accessibility. Doors and panels are attached, ensuring proper alignment with latches, locks, and gaskets for secure closure and environmental protection. Internal brackets or reinforcements may be added for strength and cable management. Final adjustments, including verifying door operation, securing fasteners, and checking fitment, ensure the enclosure meets design specifications before moving to finish and inspection. 

Surface Treatment and Finishing 

To enhance durability and aesthetics, the enclosure undergoes several finishing processes. Deburring and grinding smooth out sharp edges left from cutting and welding. Depending on the application, enclosures may receive powder coating, painting, plating, anodizing, or galvanizing to improve corrosion resistance and provide an attractive, long-lasting finish. 

Final Quality Control (QC) & Inspection 

A thorough quality control process is the final step before the enclosure is shipped, ensuring it meets all design and manufacturing specifications. These inspections guarantee the enclosure meets quality standards before final packaging and shipping.
Our process includes dimensional checks using tools like calipers, micrometers, and coordinate measuring machines (CMM) to verify tolerances. We also have dedicated, final-stage quality control inspections which guarantee every enclosure meets quality standards before final packaging and shipping. 

Weld Integrity - Weld integrity inspections involve visual examination, dye penetrant testing, or ultrasonic testing for strength and uniformity.

Surface Finish Evaluations - We check for proper powder coating, painting, or plating adhesion, often using thickness gauges and adhesion tests.

Fit and Function Testing - Fit and function tests confirm door alignment, gasket sealing, and fastener security, while environmental resistance tests, such as salt spray or IP/NEMA rating verification, ensure the enclosure can withstand its intended conditions.

Metal enclosure fabrication is a detailed process that balances design, material selection, and manufacturing techniques. Whether you need an enclosure for an industrial control panel or a rugged outdoor electronic system, understanding the fundamentals ensures you choose or build the right solution.

If you’re considering a custom enclosure, working with a skilled fabrication partner can help you balance durability, protection, and cost-efficiency. Need help designing an enclosure? Contact our team!