As a product designer, especially of manufacturing products, there’s a pretty darn good chance you know how valuable sheet metal prototype fabrication is in product development. Yet, you might be unsure about how sheet metals are fabricated or the best tech drawing design for sheet metal structures.
Components that are made of sheet metal are widely employed in engineering applications owing to the benefits associated with using sheet metal. Metal in the form of thin slabs of varying thickness is known as sheet metal. These slabs can be utilized in different applications by performing operations such as cutting and bending. Sheet metal is used to make a wide range of daily goods. Thicknesses can vary greatly; extremely thin sheets are designated as foil or leaf, while pieces thicker than 6 mm are identified as “plate or structural steel”.
Traditionally, in the United States of America (USA), the gauge is used as the system through which the thickness of the sheet metal is indicated. The gauge system is nonlinear and steel sheet metal is commonly used in gauges ranging from 30 gauge to roughly 7 gauge.
Sheet thickness in the gauge system differs for ferrous and nonferrous metals. For example, the thickness of copper sheets is measured in terms of ounces per square foot. Sheet metal parts must have a consistent thickness for optimal results.
Sheet metal prototyping
The need for quickly and easily manufacturing metal parts can be met through sheet metal prototyping. There are geometric restrictions on the type of parts that can be produced through sheet metal prototyping. For example, complex geometric shapes that involve varying cross-sectional thickness cannot be manufactured through sheet metal prototyping operations and must be machined or cast instead. However, there are plenty of applications where simpler geometries lend themselves to be manufactured through sheet metal operations in large quantities.
Steel sheet metal is available in different grades. Steel sheets of grade 304 have strong corrosion resistance while yet being formable and weldable. For high-temperature applications, grade steel 316-grade sheets are used as this grade shows superior strength and corrosion resistance properties. This grade is preferred for applications in the marine industry.
Aluminium is a prominent metal used in sheet metal because of its flexibility, variety of possibilities, low cost, and other features. 6060-T6, 1100-H14, 3003-H14, and 5052-H32 are the most commonly used aluminium grades in sheet metalworking.
Grade 1100-H14 is ductile enough for deep drawing and weldable, although it’s weak. It has high weather and chemical resistance. Grade 3003-H14 has more strength than the 1100 series. It is relatively cheap and formable. It can be joined through welding. Grade 5052-H32 is substantially stronger than the 3000 series. It is also formable. It has excellent corrosion resistance and weldability. Electronic chassis, tanks, and pressure vessels are examples of common applications. Grade 6061-T6 is the most commonly used aluminium alloy used in aerospace applications. T6 represents that this alloy is heat-treated. As compared to the 5000 series, it has better strength and welding properties but lacks in formability.
Brass sheets are commonly used for metal forming operations. When compared to copper, it offers greater strength, corrosion resistance, and formability while preserving its conductivity.
Variation in entering sheet coil characteristics is a common challenge for the forming process in sheet hydroforming, particularly with materials for automotive applications. Despite the fact that arriving sheet coil may fulfil tensile test criteria, large rejection rates are frequently recorded in production due to unpredictable material behaviour. As a result, there is a considerable demand for a discriminating method for checking the formability of incoming sheet material. The hydraulic sheet bulge test simulates biaxial deformation situations that are prevalent in manufacturing processes.
Hems are frequently used to reinforce an edge, conceal burrs and uneven edges, and enhance aesthetics. Seams are often employed in the food business on canned foods, amusement park cars, metal roofing (using a roof seamer), and the automobile sector.
In Single Point Forming (SPF), also known as Incremental Sheet Forming (ISF), deformation is incurred in small steps to achieve the final shape. However, research has revealed that it may also be used on polymer and composite sheets. Computer Numeric Control (CNC) or robotic arm is used to hold the tool. The tool applies force on the sheet, creating small indentations that accumulate in the achievement of net shape. The tool sued in incremental forming is mostly round in shape. For certain cases, die can also be used to aid the process of final shape achievement. ISF is classified based on the number of contact points. In the case of using a flat plate is used to support the sheet while the tool is working on the sheet, only single point contact is formed. In case a die is also being used, the contact points in ISF increase to two.
Hydroforming involves using water to form the sheet metal in the desired shape. Laser cutting is a modern tool used to cut sheet metal in a precise manner. Other techniques include shearing, blanking, punching, bending, stamping, drawing, embossing, roll forming, sheet metal bending, and sheet metal curling.
The applications of sheet metal prototyping
Sheet metal is used in automobile and truck hulls, airplane fuselages and wings, hospital tables, building roofs (architecture), and a variety of other uses. Ferrous materials are used in transformers and other electrical applications due to their magnetic and structural properties. Another important factor is the expenses incurred as compared to other manufacturing processes. When compared to machining, sheet metal offers the advantage of less material waste and hence, it is economically more feasible. However, there are certain limitations associated with the process as well. These limitations include failure to achieve intricate and complex geometric features.
Sheet metal was historically used extensively in cavalry plate armor, and it is now used for a variety of aesthetic purposes, including harnesses.
For different electronic systems to be used in different applications, it is imperative to design an enclosure that meets the relevant requirements i.e. thermal management, weight limitations, structural integrity, etc. Server racks are made from sheet metal. In the avionics industry, it becomes even more important for proper enclosure design and sheet metal operations to meet structural requirements while minimizing the weight.
Car customization is one of the most prominent applications of sheet metal fabrication. For can customization personal preference takes precedence. Sheet metal work is extensively used during the initial manufacturing and assembly of vehicles. It is even more important when it comes to customizing. Another important application is in the automotive industry is related to the restoration of vintage cars.
For aerospace applications, sheet metal of multiple materials is used depending on the requirement. Requirements include components’ abilities to bear harsh conditions such as temperature variations, humidity, and extended periods of vibrations. Irregularities and weaknesses must be minimized, which is what our sheet metal fabrication for the aerospace production line is meant to do.
Sheet metal is used extensively in engineering applications. Reasons for such widespread use of sheet metal include easy availability, multiple material options, and multiple manufacturing processes available. Stainless steel, aluminium, and brass are the most commonly used material. Whereas, hydroforming, bending, seaming, and incremental sheet forming are some of the common manufacturing methods employed. Applications of sheet metal prototyping are in the field of aerospace, automotive, and electronics.