Vacuum Bag Process

There are multiple occurrences of this process in the routing for a Composites part. Note that some costs apply only to the first occurrence.

Also note that the process occurs as a sub-process of the Hand Layup process.

Cycle Time = Labor Dependent Process Time / Number of Operators

Cycle time depends on the following:

• Labor-dependent process time (see formula)

• Number of Operators: this is the number of operators for the Hand Layup process. By default, it is specified by the machine property Number of Operators. Users can override the default on a per-part basis with the setup option Number of Operators.

Labor Dependent Process Time =

Unroll Vacuum Bag Material Time + Install Vacuum Port Time +

Tape Vacuum Bag Edges Time

Labor-dependent process time is the sum of the following:

• Unroll vacuum bag material time: time to unroll the required amount of vacuum bag material prior to taping the bag edges to the mold. See formula.

• Install vacuum port time: this is 0 for all but the first occurrence of Vacuum Bag in the current routing. For the first occurrence, this is specified by the cost model variable installVacuumPortTime (300 seconds in starting point VPEs).

• Tape vacuum edges time (see formula)

Unroll Vacuum Bag Material Time =

Tool Surface Length / Unroll Vacuum Bag Material Rate

Unroll vacuum bag time depends on the following:

• Tool surface length (see Tool Length, Width, and Area)

• Unroll vacuum bag material rate: specified by the cost model variable vacuumBagMaterialUnrollRate (300mm/sec in starting point VPEs).

Tape Vacuum Edges Time = Part External Perimeter / Vacuum Bag Apply Rate

Tape vacuum edges time depends on the following:

• Part external perimeter: specified by the geometric property External Perimeter.

• Vacuum bag apply rate: specified by the cost model variable applyVacuumBagRate (30mm/sec in starting point VPEs).

Additional Direct Costs = Vacuum Bag Material Cost + Sealant Tape Material Cost

Additional direct costs are 0 for all occurrences of this process except the first one in the routing for the current part. Additional direct costs are the sum of the following:

• Vacuum bag material cost: this is 0 for all occurrences of this process except the first one. See formula.

• Sealant tape material cost: this is 0 for all occurrences of this process except the first one. See formula.

Vacuum Bag Material Cost =

Vacuum Bag Cost per Area * Vacuum Bag Material Used

Vacuum bag material cost is 0 for all occurrences of this process except the first one. It is the product of the following:

• Vacuum bag cost per area: specified in cost per square meter by the tool shop variable costPerArea_vacuumBag).

• Vacuum bag material used: this is 0 for all occurrences of this process except the first one. During the first occurrence, this is the area of vacuum bag used, which is assumed to be equal to the surface area of the tool—see Tool Length, Width, and Area.

Sealant Tape Material Cost =

Sealant Tape Material Cost Per Length * Sealant Tape Material Used

Sealant tape material cost is 0 for all but the first occurrence of this process. It is the product of the following:

• Sealant tape material cost per length: specified by the tool shop variable costPerLength_sealantTape.

• Sealant tape material used: this is 0 for all but the first occurrence of this process. See formula.

Sealant Tape Material Used =

Part External Perimeter * Sealant Tape Length Multiplier

This is 0 for all but the first occurrence of this process. During the first occurrence, it is the product of the following:

• Part external perimeter: specified by the geometric property External Perimeter (the length of the part’s contours, excluding internal contours such as internal cutouts).

• Sealant tape length multiplier: specified by the cost model variable sealantTapeLengthMultiplier (1 in starting point VPEs). Administrators can use the cost model variable to increase the amount of tape used relative to the part perimeter, if that better reflects your manufacturing practices.