Factors Affecting Sheet Metal Parts And Joint Design

Varied metals and metal alloys can be formed into sheets and used to fabricate sheet metal parts.

Factors affecting sheet metal parts and joint design. For noncircular sheet metal parts the maximum diameter is sometimes used. Sheet metal bending is the plastic deformation of the work over an axis creating a change in the part s geometry. Sheet metal bending methods design tips k factor bending is one of the most common sheet metal fabrication operations. Selection of the type of sheet metal joint affects product design cost assembly process and its performance.

Also the buckling and torsional strength of many sheet metal and tubular parts depends primarily on the thickness of the material rather than its allowable compressive and shear strengths. Also known as press braking flanging die bending folding and edging this method is used to deform a material to an angular shape. In general distortion can be controlled to varying degrees by clamping or fixturing use of heat sinks see figure 2 and special welding techniques. Thickness to diameter ratio is a main factor used to quantify the geometry of a blank and can be calculated by t d b.

Required joint type. Distortion can be a major factor in sheet metal welding. Several factors affect the final shape and accuracy of the components including the effect of the punch and die radii the punch to die clearance the heat treatment of tooling the lubricant the press speed the press force and the blank holding pressure. Bending of sheet metal is a common and vital process in manufacturing industry.

Proper joint design and correct welding procedures limit distortion. Cutting and forming thin sheets of metal usually performed as cold working sheet metal 0 4 1 64 to 6 mm 1 4in thick plate stock 6 mm thick advantage high strength good dimensional accuracy good surface finish economical mass production low cost. Whenever sheet metal is heated some distortion will occur. Following factors affect the selection of sheet metal joining process.

See figure 8 for typical distortion in a t and butt joint. The choice of materials depends on the requirements of the application and factors in material selection include formability weldability corrosion resistance strength weight and cost. Similar to other metal forming processes bending changes the shape of the work piece while the volume of material will remain the same. The manufacturer s srm often indicates what material can be used as a substitution and how much thicker the material needs to be.

Thickness is represented by t and d b is the diameter of the blank. Since each metal fabricator has its own tooling bend factors and equipment to develop the flat blank it is better to fully dimension to formed views for that manufacturer.