Die casting is a technique for mass-producing metal products and components, and die casting mold design is one of the most important steps in the process because the shape and attributes of the mold directly affect the final product. The die casting procedure forces molten metal into molds using high pressure and it requires a mold with exact specifications to achieve the task.
The Importance of Die Casting Mold Design
Die casting molds
Mold design affects the shape, configuration, quality, and uniformity of a product created through the die casting procedure. Improper specifications can result in tool or material corrosion, as well as inferior product quality, while an effective design can improve efficiency and production time.
Factors Contributing to Quality Die Casting Mold Design
There are a number of mold design factors to consider when deciding on the appropriate specifications for a project. Some of these factors include:
- Die draft
- Parting lines
- Holes and windows
- Wall thickness
Draft is the degree to which a mold core can be tapered. A precise draft is needed to smoothly eject the casting from the die, but since draft is not constant and varies according to the angle of the wall, features such as the type of molten alloy used, shape of the wall, and depth of the mold can affect the process. Mold geometry can also influence draft. In general, untapped holes require tapering, due to the risk of shrinkage. Likewise, inner walls can also shrink, and therefore require more drafting than outer walls.
A fillet is a concave junction used to smooth an angled surface. Sharp corners can hinder the casting process, so many molds have fillets to create rounded edges and reduce the risk of production errors. With the exception of the parting line, fillets can be added nearly anywhere on a mold.
The parting line, or parting surface, connects different sections of the mold together. If the parting line is imprecisely positioned or becomes deformed from work strain, material may seep through the gap between the mold pieces, leading to non-uniform molding and excessive seaming.
Bosses are die cast knobs that serve as mounting points or stand-offs in mold design. Manufacturers often add a hole to the interior structure of the boss to ensure uniform wall thickness in a molded product. Metal tends to have difficulty filling deep bosses, so filleting and ribbing may be necessary to alleviate this problem.
Die cast ribs can be used to improve material strength in products lacking the wall thickness required for certain applications. Selective rib placement can reduce the chance of stress cracking and non-uniform thickness. It is also beneficial for decreasing product weight and improving fill capabilities.
Holes and Windows
Including holes or windows in a die cast mold directly affects the ease of ejecting a completed molding and enables the creation of substantial drafts. Additional features, such as overflows, flashovers, and cross feeders may be necessary to prevent unwanted casting within the holes or poor material flow around the holes.
Manufacturers often include brand names or product logos in the mold design of die-cast products. While symbols do not typically complicate the die casting process, their use can affect production costs. In particular, a raised logo or symbol requires additional molten metal volume for each manufactured part. Conversely, a recessed symbol requires less raw material and can reduce expenses.
Additional Considerations for Die Casting Mold Design
Some of the additional factors that should be considered before starting a die casting mold development project include the following:
- Gate calculation, feeding speed and fill time.
- Press size, clamping forces calculation.
- Shot sleeve choice and calculation.
- Venting and overflows.
- Establishing cast and technological Datums
- Establishing machining stock.
Contact us for more information regarding our die casting mold development processes.
JINGXIN is your ideal partner & factory in aluminum & zinc die casting
JINGXIN® is a full-service supplier of quality products in the aluminum die casting, zinc die casting, post process CNC machining, finish treatment in house; We are an ISO 9001:2008 and IATF 16949 certified factory in China. With our 15+ years skilled R&D Team support, We have successfully finished over 2000+ cases to our customers over the world. We have been serving customers in various fields, which include new energy automobile, LED lighting, industrial automation, communication engineering products and more.
Die Casting Mold Design & Making in House
At JINGXIN , All the die casting dies were designed and made by our R&D and workers in house. Our skilled R&D design the mold according to the drawing and production requirement, flow simulation, perpetual tooling and tool maintenance programs are utilized to extend tool life, reduce cycle times, reduce costs and provide high quality die castings.
Die Casting Workshop
With 150-1600T high precision die casting machines, to meet all die casting parts’ dimension requirements. JINGXIN® provides high pressure die casting, and a range of post process custom manufacturing such as CNC milling, CNC turning, finish treatment. parts assembly ,. etc . the integrated services required to be your complete global manufacturing resource.
Quality Assurance & Control
ISO certificated and IATF 16949 Certification. our quality policy is “Integrity Centered, Customer First, Quality Priority and Continuous Improvement”. Every steps are under ISO such as mold design, mold making, die casting, post machining fabrication.