Estimating Composites in SEER

At the highest or total parametric estimating level, SEER for Hardware (SEER-H) provides a comprehensive lifecycle cost estimate for composite processes and systems when information is limited to weight, volume and material mix. SEER-H has built-in knowledge bases that cover composite materials and manufacturing processes using its mapping databases and user selections for composite process requirements.

SEER for Manufacturing (SEER-MFG) operates at the manufacturing process level and allows you to model composites using three different approaches all of which have different levels of input and output granularity. The standard SEER for Manufacturing model comes with two modeling options: Composites Model and Detailed Composites Model. A plug-in we call SEER-Aerostructures offers more advanced modeling capabilities.

Ranging from simple to detailed state-of-the-art analysis, there are various ways by which composites estimation can be accomplished utilizing SEER models.

Composites Model

The standard SEER for Manufacturing Composites model estimates the costs of composite techniques requiring minimum inputs. This method is useful for quick, high-level trade study analysis. It provides a rapid answer when you need to obtain cost estimates for using a composite process, such as when you are doing a quick comparison of using metal vs. composites or deciding whether you want to do hand lay-up vs. spraying. The Composites Model supports the following operations/methods: Lay-up, Filament Winding, Pultrusion and Composite Spray.

Detailed Composites

SEER for Manufacturing’s Detailed Composites model provides a richer, more flexible modeling environment than the standard Composites model. This model can be used for detailed trade and design study analysis. You can describe in detail the part shape, including build-ups and cores, materials and resins, the material cutting process, the bagging process, consumable materials, hot-ply forming, curing, and trimming. You are able to model the tooling manufacture costs and inspection costs using non-destructive testing techniques. This model is used more prevalently within industry. The Detailed Composites Model supports the following operations/methods: HLU (Hand Lay-up), ATL (Automated Tape Lay-up), RTM (Resin Transfer Molding), LRI (Liquid Resin Infusion) and RFI (Resin Film Infusion).

Aerostructures (CAI)

Aerostructures Pro, which is sold separately as a plug-in to SEER for Manufacturing, provides the most detailed and flexible modeling environment. This model was developed in conjunction with the U.S. aerospace industries’ leading companies and has an aerospace-focus; however it can be used for any composite project due to the wide range of processes covered and the fact that the process models are based on time and motion studies for the process elements. When applying these standards an organization can adjust the model output to forecast their plant and equipment as well as their personnel experience levels. The plug-in offers state-of-practice as well as state-of-the-art composites modeling processes.

Aerostructures includes Composites Operations, Aero Cure and Aero Trim. Each of these three is treated as a distinct work element type, providing a great level of detail and modeling flexibility.

• With Composites Operations, you can define each ply layer in detail, specifying detailed tooling estimates, part marking, and packaging models. The Composites Operations Model supports the following Placement Methods: Braiding, Hand Layup, P4A, Tow Placement, 3D Weaving and Filament Winding.
• Cure is used for cured and infused parts. You can use this model for Pre-Preg Materials that are typically cured in an autoclave. You can also use this model for parts made up of Dry Fiber materials that have resins infused. This input defines which cure & infusion module will be used to model labor and material requirements. The detailed inputs available and resultant time alues will depend on this choice. Choose from Autoclave, E-Beam Fabrication, RTM, or VARTM
• Trim is used for the process to remove excess material, since most structural components are not fabricated to a net shape. Several methods can be used, including hand router, 3-axis, 5-axis, water jet cutting, ultrasonic knives and band saw cutting. The trim module algorithm is designed to provide estimates for the process of trimming parts or subassemblies. The module lets you input various trim lengths, material types, and thicknesses (mixed material stack-ups) along with cutter types. The module is intended to provide estimates for the trimming of individual detail parts and subassemblies.

With the plug-in, you can combine any or all of the above models as needed, giving a great deal of control over nuances of design.

Aerostructures also includes non-composite and composite enhancement processes:

• The Fitup, Drill & Fasten modules are designed to provide estimates for the process of assembling, drilling and fastener installations for detail parts or subassemblies into the next higher assembly and are flexible enough to model the smallest to the largest assemblies. All aspects of the aerospace assembly processes are covered from faying surface sealing, fuel containment sealing form, in-place gaskets as well as shimming and torque check for specific fasteners.
• Paste Bond is used to secondarily bond two materials together without using an autoclave.
• Electron Beam (or E-Beam) Assembly is a fusion process for welding joints with heat from a converted beam of high-energy electrons and is applied to composite curing techniques.
• 3-D Reinforcement has two basic processes: stitching and Z-pinning. Both are structural enhancements for composite structures and are used to add delaminating resistance and strength to the composite structure.
• Sheet Metal is comprised of a listing of possible and typical sheet metal operations for completing the sheet metal detail part being modeled. The data is based on a half a million plus parts database. Pre-Form, Form, After-Form and Finish operations are all covered.
• Superplastic Forming & Difusion Bonding (SPF/DB) is a process typically used to form flat sheets of titanium or aluminum into desired shapes using a heated die at high temperatures. The sheet or sheet pack is clamped into the die to create a gas-tight seal and then pressurized with inert gas. The part sheet or sheet pack is forced down into the die cavity through the use of very carefully controlled gas pressure until it conforms to the die. The part being formed can be made up of one or several sheets and may include inserts. Multiple sheets are welded together using several different weld methods and upon completion are very complex assemblies of multiple sheets bonded and welded together.

SEER for Manufacturing provides three answers to composite modeling with Composites Model, Detailed Composites Model and the Aerostructures Plug-in. Ranging from simple to detailed state-of-the-art analysis, SEER for Manufacturing provides the ultimate in modeling capabilities for composite estimation.