THT Staffing Audit Worksheet

This worksheet accompanies the article "One Operator, Four Machines: Why Auto Insertion Changes the THT Staffing Model". Use it to calculate the staffing impact of replacing manual THT insertion with auto insertion machines on your specific line.

Step 1: Your Current THT Staffing

Parameter	Your Value
Manual THT operators per shift	___
Number of shifts per day	___
Monthly labor cost per operator (USD)	___
Working days per month	22

Total monthly labor cost = operators per shift x shifts x monthly cost per operator

Step 2: Manual Throughput Estimate

Parameter	Your Estimate
Average CPH per manual operator	400-700 CPH
Working hours per shift	8
Working days per month	22

Estimated monthly manual throughput = CPH x 8 hours x 22 days x 60 minutes

Step 3: Automatic Insertion Comparison

Machine Model	Type	Practical CPH	Replaces (Manual Operators)
S-3010B	Radial Insertion	13,000 CPH	15-20 per shift
S4000	Axial Insertion	20,000 CPH	25-30 per shift
S-70LD	Odd-Form Insertion	Component-dependent	5-10 per shift

Estimated machine monthly throughput = CPH x 8 hours x 22 days x 60 minutes

Operators needed for machines: 1 operator per 3-4 machines

Step 4: Rework Cost Comparison

Factor	Manual Insertion	Auto Insertion
Typical rework rate	2-5%	Under 0.5%
Rework cost per board	3-10x first-pass cost	Minimal
Training time per new operator	2-4 weeks	N/A
Operator turnover impact	High	Low

Annual Savings Estimate

Annual savings = (Current labor cost - Machine operator labor cost) + (Rework cost reduction) - (Machine depreciation + maintenance)

For a custom calculation that accounts for your specific product mix, shift structure, and local labor conditions, reach out to Jason Wu at jasonwu@smthelp.com or +86 13602562576. Southern Machinery provides free line consultation and proofing for new auto insertion setups.