Polyurethane system for automobile steering wheel can be foamed and simulated
Virtual simulation design helps to increase exhaust within the mold and predict foam density distribution
Bring benefits to steering wheel manufacturers: Shorter parts development cycle, more reliable customization process
The application of BASF's Ultrasim® simulation tool has been further expanded to accurately predict foaming and curing of polyurethane elastomeric skinned foam system Elastofoam® I for use in automotive steering wheels. Through a detailed simulation process, the tool can accurately calculate the polyurethane foam at Key chemical reactions and flow characteristics in the mold. This simulation takes into account temperature, pressure, material density and other process environmental conditions as well as special components such as metal skeletons and cables. In addition, the upgraded Ultrasim is also the first time for foam systems. An overall, detailed analysis is like providing a virtual magnifier to the developer, helping them to identify the key holes in the part, adjusting the vents, and designing a stable steering wheel manufacturing process long before the mold is made. The BASF service is beneficial to the steering wheel manufacturer to shorten the development cycle, thereby reducing costs, while promoting the functional integration of the steering wheel to enhance its electronic and personalized design level. At present, the users of this tool include the TRW Automotive Security System Co., Ltd. and other automotive supplies Business.
Do not be afraid of complicated flow characteristics: Predict vent holes and density distribution accurately
In the car, the steering wheel is the most important operating part: its feel, appearance and functionality are directly related to the design of the part. Taking into account the complexity of the steering wheel structure and styling - including metal skeletons, cables, buttons and features The design, as well as the limited space inside the car, is more demanding for polyurethane foams and foaming processes. During simulation analysis, developers must collect a wealth of material data and consider the complex material laws because they all affect the filling. Characteristics and final density distribution. Compared to dashboards and other components, the accuracy of modeling must be improved when analyzing the flow characteristics of the foam material of the steering wheel: The flow channel must be divided and compounded, and the small slot must be vacant. Thicker Parts must be filled and enriched.
Exhaust performance of the mold is a particularly important parameter. During the production process, the manufacturer adopts a variety of processing methods to ensure air permeability. The vent hole is designed to prevent damage to the steering wheel's stability and appearance in the components. Porosity. The fill simulation function in the Ultrasim tool accurately predicts the position and size of the pores and helps the customer to properly place the air vents, thereby reducing the risk of voids with a relatively lean, breathable design. The precise flow model also takes into account individual components and customer-specific The process, such as installing the mold pivot in the foaming process. In these applications, the comparison between the analysis results and the customer's finished product is sufficient to verify the BASF simulation tool's accuracy in predicting flow characteristics and porosity.
The BASF simulation tool can also calculate the density distribution. The density distribution determines whether the steering wheel feel can meet the requirements of automotive manufacturers, such as the surface hardness. Predict the density of parts throughout, BASF carried out the material model used by Elastofoam I Improvements to describe the expansion of foams based on chemical reactions, ambient temperature changes, pressures and initial gas concentrations to lay the foundation for further describing the process flow of polyurethane foam steering and judging its stiffness, hardness and other mechanical properties. The Shore hardness of the steering wheel cannot be predicted at the earlier pure virtual project stage, but it can be tested in a physical test.
Elastofoam I elastic skinning foam: lightweight core, hard skin
In addition to the existing technical services, BASF also develops customised manufacturing services for flexible, self-skinning foam systems in conjunction with the new Ultrasim tool to meet specific process and component application requirements. With existing one-step processing methods, the density can be processed into density. Low, aesthetically pleasing, UV-resistant, scratch-resistant Elastofoam I self-skinning steering wheel system. The skin of the steering wheel is hard and strong, soft and comfortable to handle, excellent in abrasion resistance, and resistant to sweat, sunscreen or cleaning agents. , Durable. At present, this foam system can significantly reduce the weight of 340 g / l, and maintain a faster demolding speed (60 seconds) and lower emissions.