5. Separate nominal cycle arithmetic from qualified delivery capability
After the two expected changeovers, the nominal machining time is:
- 480 - 2 × 25 = 430 minutes;
- 430 / 3 = 143.33 nominal cycles, or at most 143 complete cycles under those assumptions;
- 120 × 3 = 360 nominal machining minutes, leaving 70 minutes before other demands on that same capacity.
This arithmetic has no allowance for yield loss, rework, interruption, loading assumptions omitted from the quoted cycle, inspection that uses the same constrained resources, or transport. It also says nothing about coating capacity, batch size, lead time or whether returned acceptable parts meet the day’s delivery boundary. Extra work on independent resources need not subtract directly from the machine’s 430 minutes, but it can still constrain delivery.
Use OPS.10.1 to construct the capacity account from the needed acceptable output, actual processing and rework passes, opening work, resource demands and provider returns. Use OPS.10.2 to place those operations within their availability and delivery constraints. The methods are available; the missing production values and their applicable limits still have to be obtained.
A changed condition can already reject a candidate without a complete production study. Suppose the day starts with no partly completed brackets and an additional 71 minutes of machine unavailability leaves 359 minutes after changeovers. Even 120 single passes require 360 minutes. Under those assumptions, this machine cannot complete the proposed day’s work. Before that change, the spare 70 minutes alone did not establish delivery through coating and return.
One conforming specimen does not establish the process distribution or its sustained behavior. The NIST/SEMATECH process-capability Method is a bounded historical statistical source: its familiar capability indices compare a stable process with specification limits under applicable distribution and sampling conditions. Qualify the measurement chain separately. Distinguish relevant variants and operating conditions, and justify any pooling before interpreting a capability index.
The remaining production contributions can now be assigned.
| Contribution needed for this production case | What its receiver needs before the dependent claim can proceed |
|---|---|
| Tooling, program and changeover qualification | An operative procedure and evidence for the intended machine, material, fixture variants, program/configuration and changeover conditions, including the failed or interrupted case. |
| Finished-part measurement and acceptance | A qualified measurement chain with applicable uncertainty and an authorized decision rule for the coated bore and identified part/lot population. |
| Sustained process capability | Suitable observations from the qualified measurement process, stability and model checks, and a justified capability result for the relevant conditions. The NIST source is used only where its Method applies. |
| Acceptable-part delivery capacity | An end-to-end result including yield, rework, constrained resources, provider capacity, transport, waiting and the actual delivery horizon; not the isolated nominal cycle count. |
| Nonconforming-material and recovery disposition | An authorized way to identify and segregate affected material, determine permitted inspection/rework/replacement or acceptance, and establish the result before reuse. |
Use the available Suite Methods for the stated constructions. Obtain or develop the physical procedures still missing, and obtain the case inputs and qualification results needed by the receiving decision. The common platform language connects those contributions.