Deep Drawings – Executing Complex Shapes with Hydraulic Presses
Deep drawing sheet metal is a form of stamping that is generally defined by the ratio of the width to the height of a finished piece, such that the height of the stamping is greater than its width. Yet, in practice, there are many applications that require this approach to metal forming, but which would fall outside this strict definition of deep drawings. There are many examples of deep drawn stampings in both the consumer durables as well as the consumer disposables industry. Items such as stainless steel kitchen sinks are an example in the consumer durables area, while beer and soda cans are examples of consumer disposable products.
Deep drawing sheet metal can be further categorized into simple shapes and complex shapes. Simple shapes are typically seamless tubular products with straight walls, while complex shapes may have non-symmetrical geometries and additional surface features such as bump-outs, recesses or holes of different dimensions or shapes. Deep drawing is usually a compound process that includes stamping – radial tension-tangential compression -and stretch-and-bend along the sides of components. The stamping action in deep drawing is always accompanied by other forming techniques within the press.
A common example of a product this type of process might be used to produce is motorcycle gas tanks. These commonly have completely unusual topologies in any given dimension and often include some beading, flanging and openings for filling and feeding fuel out to the engine.
ATACO specializes in producing complex, deep drawings and has a staff that has many years of experience planning and assisting clients design for manufacturability. In addition to staff expertise, the company has invested in large tonnage presses, up to 1700-ton, and state-of-the-art press and controls. To support extreme drawing requirements, hydraulic presses are utilized, ranging in tonnage from 400 to 1,100 tons, an unusual capability in the contract stamping industry. The controls feature state-of-the-art software, sensors I/O and drives that make it possible to vary the speed and pressure applied by a die throughout a forming stroke.
The key benefits of this technology translate to an ability to draw a wider range of materials and shapes, a more uniform grain in the deep drawn material and improved cosmetic characteristics of the finished product. Common imperfections such as pitting, surface voids, stain, wrinkles and cracks can be eliminated with proper planning.
ATACO has also acquired FASTFORM software in order to improve die design and every other aspect of the forming process, as well as the quality of the finished product. This deep drawing simulation software eliminates the traditional trial and error iterations based a tool and die maker’s best guess. It speeds up the development process by producing first time perfect dies in 90% of design cases.
The finishing touch to this deep drawing capability includes 5-axis robotic laser cutting and trimming. This complementary equipment makes it possible to add openings of any shape in any location of a deep drawn part, adding to production flexibility, reducing total capital investment for tooling , and speeding production for short, medium or long runs.
Thanks to consistent investment in equipment and staff, ATACO has developed an industry-leading capability for complex deep drawings. The breadth of materials and shapes that can be produced is one of the most extensive available in the industry. From prototypes to large runs ATACO’s design and production team can get clients quick turn samples and high quality finished products on spec, on time, on budget.