Rock bolt drilling — Skagit Bluff · 12 shifts
| Gross rate (all shift time) | 24 m/shift |
| Net rate (productive time only) | 31 m/shift |
| Shift time lost to interruptions | 22% |
Both figures are always shown together. Either alone misleads.
Where the time went
rail traffic passage ████████ 38% engineer hold █████ 24% traffic control window ████ 18% weather ███ 13% equipment ██ 7%
The engineer hold is MoTI's own rule: drilling of the next lift may not proceed until stabilization is complete and the Ministry's geotechnical engineer's concerns are addressed.
By condition
| Condition | n (shifts) | Net rate | Note |
|---|---|---|---|
| Open ground | 5 | 38 m/shift | — |
| Constrained access | 4 | 26 m/shift | traffic control windows |
| Adjacent live rail | 3 | 17 m/shift | crews disengage and reposition for train passages |
Never a rate without its sample size.
Quantities recorded without interruption reasons cannot be interpreted.
Where a shift has quantities but no interruption record, the analysis flags it rather than computing a rate from it.
Layout as specified in SCR-045-production-analysis.md
┌──────────┬────────────────────────────────────────────────────┐ │ NAV │ Production analysis [work type ▾] [project ▾] │ │ ├────────────────────────────────────────────────────┤ │ │ ROCK BOLT DRILLING · Skagit Bluff · 12 shifts │ │ │ │ │ │ gross rate (all shift time) 24 m/shift │ │ │ net rate (productive time only) 31 m/shift │ │ │ ──────────────────────────────────────── │ │ │ 22% of shift time lost to interruptions │ │ ├────────────────────────────────────────────────────┤ │ │ WHERE THE TIME WENT │ │ │ rail traffic passage ████████ 38% │ │ │ engineer hold █████ 24% │ │ │ traffic control window ████ 18% │ │ │ weather ███ 13% │ │ │ equipment ██ 7% │ │ ├────────────────────────────────────────────────────┤ │ │ BY CONDITION │ │ │ open ground n=5 net 38 m/shift │ │ │ constrained access n=4 net 26 m/shift │ │ │ adjacent live rail n=3 net 17 m/shift │ │ ├────────────────────────────────────────────────────┤ │ │ [ contribute to rate library ] │ └──────────┴────────────────────────────────────────────────────┘
Implements spec/03-screens/SCR-045-production-analysis.md · SCR-045 · URL /production/analysis · Personas SUPV, OWN · Stories US-SUPV-007