The document discusses several key metrics for evaluating equipment throughput and process reliability in circuit board assembly: - Effective throughput calculation considers factors like machine de-rate based on statistical run data, parts per million defects, changeover time, board load/unload time, and downtime. - First pass yield measures the percentage of total components run without defects. - Intrinsic availability calculates uptime as a percentage based only on repair and recovery downtime. - Placement repeatability and error measurements are based on attribute and variables data from insertion processes. - Cost per insertion is calculated based on equipment, replacement parts, operator labor, and maintenance costs divided by the number of components inserted.

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Equipment Throughput Calculation
• Simplistic Throughput Calculation
– Deduct a basic rule of thumb percentage from the
maximum machine cycle rate.
– The accuracy of this method is highly questionable.
• Effective Throughput Calculation
– Machine de-rate calculated using statistical data based
on actual run data and component counts.
– Also considers PPM, Product Changeover, Board
Load/Unload Time, and Downtime.

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First Pass Yield
Total Components Run - Defects
Total Components Run
X 100

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Intrinsic Availability
Productive Time
Productive Time + Repair Time
X 100
Intrinsic Availability is the percentage the
machine operates based on down time attributed
to relevant interrupts and active repair or
recovery time only.

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Total Components Run - Insert Errors
Total Components Run
X 100
Insertion/Placement Reliability

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• Placement
Repeatability for
through-hole is not
measurable.
Placement Error/Repeatability
• Placement error is
based purely on
attribute data.
• No meaningful
variables data has ever
been defined for
through-hole
processes.

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Sum
Cost Per Insertion
• CPI Calculation
Equipment Depreciation Expense
Replacement Parts Cost
Operator Labor Cost
Maintenance Labor Cost
Divided By
Number of Components to Be Inserted

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Process Issues
• Sequence of insertion
– Interconnect (Eyelet, Pins, Terminals)
– DIP
– Axial
– Radial

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Axial Lead Length, Direction and Angle
• Lead Angle Adjustable from 45-90 Degrees
• Lead Length Adjustable from 1.28 - 1.80mm
Process Issues

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Radial Lead Length and Angle
Lead Length and Angle Hard Tooled (Refer
to GS for Selections and Spec.)
Process Issues

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Process Issues
• Variables to Lead Length and Angle
– Lead Material
– Lead Diameter
– Hole Diameter
– Lead Hardness

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Radial Lead Direction “T” Style
Process Issues

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Radial Lead Direction “N” Style Clinch
Process Issues

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Axial Head Tooling
Process Issues

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Axial Clinch Tooling
Process Issues

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Radial Head Tooling
Process Issues

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Radial Head Tooling
Process Issues

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Radial Head Tooling
Process Issues

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Radial Clinch
Process Issues

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Printed Circuit Board Design Considerations
Process Issues