Standardized work: sequence, takt and standard WIP

Standardized work: sequence, takt and standard WIP

A production standardized-work chart combines the demand reference, operator sequence and required in-process stock on the physical layout. It makes the agreed method visible where work occurs. Observe the current method first, agree a safe sequence with the team and mark the inventory needed for the cycle to function. Then trial the arrangement and revise the chart when learning changes the method. A written instruction can explain an operation in detail but may omit these relationships. The chart is an improvement baseline, not evidence that variation has vanished or that faster work is automatically safe.

Follow the method

1. 1. Collect kit
2. 2. Perform task
3. 3. Check output
4. 4. Handoff

Audit the route, clocks and stock positions

Fictional bench case: operator Mara collects a verified kit, performs the task, checks output and hands off before returning to the kit point. The supplied teaching layout has takt 80 seconds per required unit and two standard in-process units: one at Work and one at Handoff. No observed cycle time is supplied.

Follow the method

1. Takt
2. Cycle
3. Sequence
4. Standard stock
5. Quality

The route is more than four instructions

Read a standardized-work route with its takt, sequence and standard in-process stock, then identify what must change when the physical route or stock position changes.

Fictional bench case: operator Mara collects a verified kit, performs the task, checks output and hands off before returning to the kit point. The supplied teaching layout has takt 80 seconds per required unit and two standard in-process units: one at Work and one at Handoff. No observed cycle time is supplied.

Role: Operator and team leader reviewing the current method together.

Normal condition

The displayed chart matches the agreed route, material positions, quality checks and operating basis.

The gap

A replacement poster lists the four verbs but omits the return route and stock locations.

• Two units and the layout are illustrative settings, not validated operating requirements.
• A posted chart does not replace approved quality, safety or training instructions.

1. Orient the reader in the workplace

   Mara locates each of the four positions on the plan view and draws the operator’s route in order, including the return to the start. She distinguishes movement from the material’s processing status.

   Why: An ordered list alone does not reveal travel, crossing or the relationship of stock to the operator.

   Evidence: Route: Collect → Work → Check → Handoff → Collect.

2. Attach the required operating basis

   Record 80-second takt as the demand reference and leave actual cycle time unmeasured until observation. Show one standard unit at Work and one at Handoff.

   Why: The chart combines timing reference, work sequence and the stock needed for its stated method. It must not report a target as an observed cycle.

   Evidence: Two marked stock locations total two units; timing fields remain distinct.

3. Retain the acceptance and exception points

   Mark where identity is checked, where output acceptance occurs and how an abnormal condition gets help. Reference the controlled work instruction for detailed criteria.

   Why: A route can appear shorter after a check is omitted, but that changes the required work. The chart should expose checks rather than hide them in a caption.

   Evidence: Check output remains before Handoff; unverified output has no ordinary handoff event.

4. Compare the drawing with one actual cycle

   Observe the agreed method with the operator under local rules. Record any extra reach, waiting, travel or stock needed to sustain it; do not alter the workplace solely to match the poster.

   Why: The chart is a baseline for learning. A mismatch is evidence to investigate with the person doing the work.

   Evidence: Observation sheet records discrepancies and their operating condition; no achieved cycle value is invented.

5. Control the revision and teaching

   If a trial changes a location or sequence, revise the chart, timing evidence and affected instruction together. Coach the new method and verify understanding before retiring the old version.

   Why: An attractive new drawing cannot establish competence or prove the layout feasible.

   Evidence: Revision owner, effective condition and observed operator demonstration are recorded.

Handoff is moved behind the bench

A proposal moves Handoff to a new position and adds a return walk not shown on the original chart.

Mark the proposed route separately, observe the added movement and reassess timing, access and stock.

The old chart’s arrows and assumptions no longer represent the proposed method, even though the four step names are unchanged.

Before/proposed drawings and measured route evidence accompany the review.

Run a practice session

Materials

• Plan-view sheet and movable station/stock symbols
• Separate quality-check and return-arrow symbols

1. Walk the drawing with a finger · 4 minutes

   Where does the operator return after handoff?

2. Audit stock and clocks · 8 minutes

   Which value is a requirement and which is missing observation?

3. Repair the second-cell draft · 8 minutes

   What can you correct without inventing a time?

4. Plan a controlled revision · 5 minutes

   How will you know the drawing matches the taught work?

Debrief

• Ask why two stock symbols cannot stand for three units without an explicit legend.
• Retain the check step when participants seek a shorter route.

Trace a full cycle, then reconcile each stock symbol and timing field with the stated setting.

Transfer into the work

Owner: Process owner and trained operator representative

Record: Current/proposed chart, observed route and revision/training evidence

Review: During the method trial and at the agreed standard-work review

Evidence: Complete route, accurate stock positions and demonstrated acceptance/response steps

Investigate the mismatch; do not demand compliance with a drawing that has not been shown feasible.