6.1 Maintenance Governance: KPIs, Roles, Escalation

Total Productive Maintenance (TPM) is not a cleaning schedule; it is the operationalfiscal methodologydiscipline usedof Asset Utilization. In high-volume electronics, a machine sitting idle due to maximize"unplanned downtime" is actively burning capital. We shift the operational efficiency of manufacturing equipment. It shifts the paradigmmodel from "repairingRepair when broken"Broken" to "maintainingMonitor to prevent failure.Prevent." InThe the context of high-volume electronics manufacturing, TPMgoal is thenot primarymerely driverto forfix minimizingmachines, unscheduledbut downtimeto and stabilizingstabilize process capability (Cpk). Thisso chapterthat definesyield theis calculationa ofconstant, Overallnot Equipmenta Effectiveness (OEE) and mandates the execution of Autonomous Maintenance.variable.

Overall Equipment Effectiveness (OEE)

OEE is the definitivenon-negotiable metric forof equipment productivity.truth. It is calculated asexposes the product"hidden factory" of Availability,slow Performance,cycles and Quality.micro-stops. The facility target for critical SMT assets is > 85%.

Formula: OEE = Availability x× Performance x× Quality

1. Availability (A)

Measures the percentage of scheduled time that the equipment is capable of operating.

• Calculation:Definition: (PlannedThe Productionratio of Run Time - Unplanned Downtime) /to Planned Production Time
• Loss Drivers: Equipment failure, material shortages, setup/changeover time.Time.
• Mandate:If Setup timesChangeover (SMED) must betakes <> 15 minutes per-> Then the process is Failed.
  • Constraint: Pre-stage feeders and stencils off-line while the machine is running the previous batch.
• If Material Shortage stops the line changeover.-> Then Log as "Logistics Loss," not "Maintenance Loss."

2. Performance (P)

Measures the speed at which the equipment runs relative to its designed cycle time.

• Calculation:Definition: (TotalNet CountSpeed /vs. Run Time) / IdealDesigned Cycle Time
• Loss Drivers: Minor stops (jams, pickup errors), speed throttling (running machines slower than rated spec).Time.
• Mandate:If MachinesMachine must not beis throttled below < 95% of rated speed without-> writtenThen engineeringEngineering justification.Justification is required.
  • Physics: Running a chip shooter at 80% to "save the nozzles" masks the root cause of the nozzle failure (likely vacuum leaks or contamination). Fix the vacuum, restore the speed.

3. Quality (Q)

Measures the yield of Good Units produced relative to the Total Units started.

• Calculation: (Total Units - Defective Units) / Total Units
• Loss Drivers: Solder defects, misplacements, scrap.
• Mandate:Definition: First Pass Yield (FPY) of good units.
• If FPY at AOI must exceeddrops < 98.5%. -> Then Stop the line.
  • Reason: Producing bad boards faster improves OEE Performance but destroys OEE Quality. Net output is zero.

Pro-Tip: Do not accept "Idle" as a status code. Configure the MES to force the operator to select a specific reason (e.g., "Waiting for Parts," "Nozzle Jam") before the machine can restart. "Idle" is data fog.

The Pillars of TPM

ImplementationMaintenance reliesis ona specifictiered pillarsresponsibility tailoredstructure, tonot thea facilitysiloed infrastructure.department.

Pillar 1: Autonomous Maintenance (AM)

Operators are the first line of defense. AM transfers routine maintenance tasks from technicians to machine operators to ensure early detection of abnormalities.

• CleanRole: &The InspectMachine Operator.
• Logic:: OperatorsThe person closest to the machine must cleandetect sensors,the nozzles,drift before it becomes a failure.
• Mandate:
  • Start of Shift: Clean sensors and transport rails at the start of every shift.rails.
  • LubricationWeekly:: Operators must verify lubricant levels and apply grease to accessibleInspect linear guides weekly.and verify grease levels.
  • TaggingTagging:: OperatorsApply musta applyphysical "fuguai" (abnormality) tagstag to any looseleak, bolts, leaks,noise, or noisesloose bolt for technician review.

Pillar 2: Planned Maintenance (PM)

Time-based or condition-based maintenance performed by skilled technicians to restore equipment to original condition.

• SchedulingRole:: PMSkilled tasksTechnician.
• Logic: Restore assets to "Day 1" condition based on usage, not calendar.
• Mandate:
  • Trigger: PMs are triggered by run-hoursRun-Hours or Cycle Counts (e.g., 10001,000 hours)hrs), ornever cycleby counts,"Months." notA calendarmachine days.running 24/7 wears out 3x faster than one running single shift.
  • PartsParts: Replacement:Replace Wearfilters partsand (filters, belts, vacuum cups) are replaced preemptivelybelts based on MTBF (Mean Time Between FailureFailure), (MTBF)before data,they not upon failure.snap.

Pillar 3: Focused Improvement (Kobetsu Kaizen)

Cross-functional teams analyze major losses to eliminate root causes.

• TriggerRole:: AnyCross-Functional downtimeTeam event(Process exceeding+ Maintenance).
• Logic: Eradicate chronic losses.
• If Unplanned Downtime > 60 minutes triggers-> aThen mandatoryMandatory Root Cause Analysis (RCA).
• Output:Output: CorrectiveA actions must includephysical hardware modificationschange or proceduresoftware updatesinterlock (Poka-Yoke) to prevent recurrencerecurrence. "Retraining operator" is not a valid corrective action.

Downtime Escalation Matrix

Escalation is not about "reporting trouble"; it is about unlocking resources to shorten Mean Time To Recovery (Poka-Yoke)MTTR). The technician owns the repair, but management owns the barrier removal.

• Level 1: Tactical Support (15 Minutes)
  • Trigger: Machine Down > 15 Minutes.
  • Who: Notify Maintenance Lead.
  • Action: Lead assesses if the technician needs additional hands or diagnostic tools.
• Level 2: Resource Allocation (60 Minutes)
  • Trigger: Machine Down > 60 Minutes.
  • Who: Notify Operations Manager.
  • Action: Manager authorizes expedited shipping for spare parts, approves overtime, or triggers the decision to re-route production.
• Level 3: Strategic Response (4 Hours)
  • Trigger: Machine Down > 4 Hours.
  • Who: Notify Plant Director.
  • Action: Activate Business Continuity Plan (BCP). The Director assumes responsibility for client communication regarding schedule slippage.

Digital Tracking & Reporting

Manual logslogbooks are insufficientdata forgraveyards. OEEIf analysis.the machine state is not in the MES, it didn't happen.

• MES IntegrationConnectivity:: All pick-and-place machinesSMT and reflowReflow ovensassets must push live state codes to the server.
• Visualization: OEE must be networked to the Manufacturing Execution System (MES).
• State Codes: Equipment must automatically report state codes (Running, Idle, Error, Setup). Generic "Idle" codes are prohibited; operators must select specific reason codes (e.g., "Waiting for Parts").
• Dashboarding: Real-time OEE data must be visualizeddisplayed on line-side Andon boards.boards in real-time. Hiding the score hides the problem.

Final Checklist

Metric / Pillar	Parameter	TargetMetric / MandateRule	Critical State
OEE Target	OverallComposite TargetScore	> 85%
AvailabilityChangeover (SMED)	Changeover TimeDuration	< 15 Minutes
Performance	Speed RatingDerating	>Prohibited (< 95% Rated Speed)
Quality	FirstFPY Pass YieldTarget	> 98.5%
AMEscalation L1	OperatorNotify TaskLead	Clean> &15 Inspect DailyMinutes
PMEscalation L2	TriggerNotify Manager	Run-Hours> /60 CyclesMinutes
ImprovementRCA Trigger	RCADowntime TriggerDuration	> 60 Min DowntimeMinutes
ReportingData Logging	Data SourceMethod	Auto-MES (No Manual)Paper)