Designing with sheet metal requires considering several key guidelines to ensure manufacturability, functionality, and cost-effectiveness. Here’s a summary of important guidelines:
1. Material Selection
Material Type: Common sheet metals include steel (carbon, stainless), aluminum, and copper. Choose based on mechanical properties, corrosion resistance, and cost.
Material Thickness: Thickness (gauge) affects bend radius, forming limitations, and strength. Ensure the material thickness is appropriate for the design.
2. Bend Radius
Minimum Bend Radius: To avoid cracking and maintain strength, the inside bend radius should generally be at least equal to the material thickness.
Bend Allowance: Account for material stretching during bending by calculating the correct bend allowance and k-factor.
Bend Relief: Provide bend relief cuts to avoid tearing or distortion at the ends of the bends.
3. Bend Direction
Grain Direction: Bends should be made perpendicular to the material grain to reduce the risk of cracking.
Uniform Bends: Ensure that all bends are consistent in radius to simplify tooling and reduce costs.
4. Hole and Slot Placement
Hole Distance from Edge: Holes should be placed at least 1.5 times the material thickness away from edges or bends.
Hole Size: The minimum hole diameter should be at least the thickness of the sheet metal.
Slot Design: Keep slots away from bends and edges to avoid weakening the part.
5. Forming and Flanges
Flange Length: The minimum flange length should be 4 times the material thickness.
Hemming and Seaming: For improved edge strength, consider hemming (folding over) or seaming edges.
Form Height: The height of any form should be less than the die width to avoid issues in the forming process.
6. Notches and Tabs
Notch Size: Notches should be at least 1.5 times the material thickness deep and spaced apart by at least the material thickness.
Tab Design: Tabs should be at least 3 times the material thickness wide to ensure they don’t break during bending.
7. Tolerances
Bending Tolerances: Typically, bending tolerances are ±0.005 inches (0.13 mm) for precise work.
Hole Tolerances: Standard hole position tolerances are typically around ±0.010 inches (0.25 mm).
8. Design for Assembly
Fasteners and Joining: Consider self-clinching fasteners, spot welding, or riveting as common joining methods. Design holes and features to accommodate these.
Ease of Assembly: Design parts to be easy to assemble, with features that facilitate alignment and fastening.
9. Surface Finish
Surface Treatments: Consider the end-use environment. You may need to specify coatings like anodizing, painting, or galvanizing for corrosion resistance or aesthetic purposes.
Deburring: Ensure that all edges are deburred to avoid sharp edges that could cause injury or interfere with assembly.
10. Cost Considerations
Material Utilization: Optimize nesting and cutting patterns to minimize waste material.
Tooling Costs: Standardize bends, holes, and other features to reduce tooling complexity and costs.
Design Complexity: Simplify design where possible to avoid unnecessary complexity that could drive up production costs.
These guidelines help ensure that your sheet metal design is both manufacturable and functional while controlling costs.
Click sheet metal fabrication company china or china sheet metal forming manufacturers to learn more about sheet metal fabrication services.
For all your electrical enclosures from China, contact china sheet metal fabrication factory JIATONG now.
From Sheet Metal Fabrication Companies in China, china sheet metal fabrication manufacturers, china sheet metal fabrication companies – JIATONG