Direct answer
Start-up, stop and restart procedures should keep the bottle, closure and machine state unambiguous and prevent uncertain packs entering accepted production.
Before start-up, verify line clearance, format parts, settings, cap supply, bottle flow, inspection and downstream readiness. After a fault or stop, identify bottles whose capping status is uncertain, correct the cause, restore the intended machine state and approve the first acceptable packs before normal release. Shutdown should leave components, records and equipment in the defined end-of-run condition.
Final machine settings, checks and release criteria must be based on the actual bottle, closure, product condition, machine configuration and site quality system. The guidance below provides a structured engineering route without replacing application-specific trials or a competent site assessment.
Operating sequence
Define the pack and machine state at every transition.
A controlled sequence prevents bottles with missing, loose, double-applied or uncertain closures from being mixed with accepted production. The exact procedure belongs in the machine instructions and site system, but the project specification should state the required states, checks and responsibility.
| Phase | Control objective | Evidence or decision |
|---|---|---|
| Pre-start line clearance | Confirm the previous product, bottles, caps, labels, tools, records and rejected packs have been removed or identified as required. | Clearance record, correct components, correct tooling and authorised format setup. |
| Controlled start-up | Establish bottle flow, cap supply, capping state, inspection and downstream availability before releasing normal production. | First-off samples, machine settings, cap-feed condition and approval record. |
| Normal stop | Stop in a known sequence that avoids uncontrolled bottle queues, cap overfeed or partially processed packs. | Machine-state sequence and defined treatment of bottles in each zone. |
| Fault stop and restart | Contain the uncertain zone, correct the cause, verify machine state and re-establish first acceptable production. | Fault record, last known good point, affected bottles, restart checks and approval. |
| End-of-run shutdown | Clear or secure bottles and closures, record remaining materials, clean as required and leave the equipment in the defined safe state. | Line clearance, material reconciliation where applicable, cleaning and shift handover. |
Pack control
Define what happens to bottles between the last known good result and the first verified good result after restart.
A restart procedure should not assume that every bottle already inside the line is acceptable. The project team should agree whether bottles are rejected, quarantined, reworked or reinspected and how the boundary is identified.
Identify the uncertain zone
Map bottles between the relevant inspection point, capper, conveyors and downstream machine at the moment of stop.
Prevent uncontrolled release
Use the available stops, gates, reject logic and operator instruction to keep uncertain packs separate.
Restore the machine state
Confirm tooling, settings, sensors, cap presentation, guides and connected-machine conditions before restarting.
Approve first accepted output
Apply the agreed cap position, torque, leak, orientation or tamper checks before normal production resumes.
Roles and records
Assign who starts, verifies, releases and records each stage.
Operators, engineers and quality personnel may have different responsibilities. The sequence should state who can clear a fault, who approves the first-off pack, who releases contained bottles and which record is retained.
| Question | Why it matters | Project evidence |
|---|---|---|
| Who owns the start command? | Prevents machines starting before cap supply, bottle flow or downstream equipment is ready. | Control narrative and operating instruction. |
| Who approves first-off packs? | Keeps machine readiness separate from product-quality release. | Approved checks and named role or function. |
| How is the last known good bottle identified? | Defines the containment boundary after a fault or inspection failure. | Inspection position, time or bottle sequence and reject path. |
| What remains site-dependent? | Utilities, connected equipment and local procedures may not be fully represented at factory testing. | FAT/SAT split and commissioning action list. |
Buyer questions
Questions production, engineering and procurement teams ask.
Each answer is written so the project team can turn a broad question into evidence for specification, testing and handover.
What should be checked on the first bottles after start-up?
Use the finished-pack checks relevant to the closure: cap position, thread engagement, torque or opening method, leakage, tamper feature, pump or trigger orientation and visible damage. Also confirm bottle flow and cap-feed behaviour before accepting sustained output.
What should happen to bottles already inside the line after a fault stop?
Treat the defined zone as uncertain until the process state is known. Depending on the site procedure, bottles may be rejected, quarantined, reinspected or reworked. The method should identify the last known good result and prevent uncontrolled release.
Should the cap feeder run before bottles enter the capper?
The sequence depends on the system, but automatic production normally needs a stable supply of correctly oriented caps at the transfer point before continuous bottle release. The control narrative should prevent bottle flow when the cap supply cannot support the application step.
Is routine start-up the same as commissioning?
No. Commissioning establishes and proves the installed system, settings, interfaces and procedures. Routine start-up uses that approved configuration for each production run or shift. A commissioning gap should not be hidden inside an operator start-up instruction.