I. Core Formula
The core formula for processing costs. According to industry standards, the calculation logic is straightforward: the processing cost per unit equals the machine’s hourly rate multiplied by the processing time, plus the tooling cost divided by the tool’s lifespan.
A more comprehensive approach involves summing the man-hours for each process step and multiplying them by the corresponding equipment hourly rate: first, list the processing steps (blanking, turning, milling, drilling, grinding, inspection); estimate the processing time (including setup/clamping) for each step; then multiply by the equipment’s hourly rate and sum the totals. Costs for programming, management, and transportation typically account for no more than 15% of the total.
II.
Reference Hourly Rates for Equipment
Hourly rates for common equipment.
Based on industry benchmarks: standard 3-axis machining centers cost 60–80 RMB/hour; economical CNC lathes cost 60–100 RMB/hour (with high-end slant-bed turn-mill centers costing more); standard machining centers are around 100 RMB/hour; milling machines are 50 RMB/hour; wire-cut EDM rates are 20 RMB/hour (fast-wire), 45 RMB/hour (medium-speed wire), and 80–160 RMB/hour (slow-wire); high-speed machines are 200 RMB/hour; vertical machining centers are 250–500 RMB/hour; 5-axis machining centers are 500–900 RMB/hour; and laser cutting is approximately 8 RMB/minute. Equipment grade directly determines the hourly rate;
5-axis machines can cost ten times as much as 3-axis machines.
III. Material Cost Calculation
How to calculate material costs.
According to national costing standards, the material cost for non-standard equipment is calculated as the net material quantity multiplied by (1 + processing loss coefficient) and then by the comprehensive unit price. You pay for the price of the raw stock (blank) rather than the weight of the finished part; waste from large clamping allowances is factored directly into the cost. Material costs are transparent: hard metals are quoted by the kilogram, and premium materials like 6061 aluminum and 316L stainless steel cost two to five times more than standard materials. The core processing fee consists of material costs, machining time charges, and tool amortization.
IV.
Batch Size and Amortization
Batch size affects unit price and the amortization of programming and setup costs.
Industry experience shows that batch size dictates the price: a single unit costs vastly different from a batch run. A single unit must absorb the costs of programming, machine setup, and tooling/fixtures (e.g., CNC turning at 80 RMB/hour and machining centers at 100 RMB/hour; while a half-hour machining job might only cost 50 RMB, the additional programming, setup, and tooling costs can push the single-unit price over 300 RMB). The larger the batch, the more these setup and programming costs are diluted. Small-batch customization is expensive precisely because one-time programming and setup costs cannot be spread across a large volume;
therefore, batch prices and single-unit prices should be evaluated separately.
V.
Methods for Verifying Quotes
When verifying a quote, industry practice suggests focusing on three areas: check material costs by multiplying net weight and the loss coefficient by the comprehensive price to ensure gross weight isn’t being charged as net weight; verify the duration of each process step plus setup time to prevent inflated labor hours; and question any instance where tool amortization and programming/management fees exceed 15% of the total. Note that sheet metal work involves independent pricing methods—such as 8 RMB/minute for laser cutting, 1 RMB per small hole, bending starting at 1 RMB per fold, and daily rates for welding. A quote is truly transparent only when its line items can be individually verified.
Conclusion
How are processing costs calculated for non-standard assembly line components? The answer is a cumulative sum of labor costs (hourly rate × time), material costs, and amortized expenses. The core formulas are: unit processing cost = (machine hourly rate × processing time) + tooling amortization; material cost = net usage × waste factor × composite price. Reference hourly rates are: CNC turning (60–100 RMB), machining centers (100 RMB), milling machines (50 RMB), wire-cut EDM (20–45 RMB), slow-feeding wire-cut EDM (80–160 RMB), 5-axis machining (500–900 RMB), and laser cutting (8 RMB/minute). There is a vast price difference between single-unit and batch production: single units must absorb programming, machine setup, and tooling costs, whereas batch production spreads these costs out, significantly lowering the unit price.
Industry practice dictates that materials, processing time, and tooling constitute the primary costs, while programming, management, and transportation should not exceed 15% of the total.
By requiring suppliers to itemize processing times and hourly rates by operation, and to verify material costs based on net weight plus a waste factor, processing costs can be calculated with complete transparency.
