Can a Colored Protective Case be accepted by eye alone?

Answer: No. Eyes cover the cosmetic lines; wall, retention, drop and salt spray need instruments. Visual-only batches typically run above 5 percent rework.

Is 13 pieces enough, and does a larger batch need more?

Answer: Follow the AQL 1.0 size; a 1,200-unit batch takes 21. More samples do not change the criterion, they cut the escape probability, and doubling cuts it to a quarter.

Supplier report or third-party report, which do you trust?

Answer: Both, and they must agree. The supplier report ties to batch and mould, the third party covers destructive tests. On conflict, the on-site reading decides.

Where does the 6 percent concession figure come from?

Answer: From rework cost. Rework is 38 yuan against a 62 yuan unit, so beyond 6 percent the discount no longer covers handling and rejection is cheaper.

Colored Protective Case Rework at 4.6 Hours: Six Checks

Quick answer: Acceptance cost for a Colored Protective Case sits in rework and rejection, not in inspection hours: 4.6 hours and 38 yuan per reworked unit, 24,000 yuan for a rejected batch. Fix the judgement lines in the contract and both stay small.

What Acceptance Really Costs on a Colored Protective Case
Which Document Wins: Drawing, Factory Standard or Contract
Six Tools, Three Readings on the Line
Appearance and Colour: Four Judgement Lines
Rework, Concession or Rejection: Three Cost Tiers
Sampling and Records: Closing the Escape Route
FAQ

1. What Acceptance Really Costs on a Colored Protective Case

Buyers negotiate the unit price and meet four other bills at goods-in: rework, concession, rejection and line stoppage.

Cost item	Trigger	Basis	This case
Rework	Weak latch, mismatch, flash	Labour per unit	4.6 h, 38 yuan
Concession	Appearance only, function passes	Batch discount	6 percent of value
Rejection	Wall or size out of tolerance	Full value plus freight	24,000 yuan
Line stop	No stock, parts unusable	Per line per hour	420 yuan

Rework looks cheapest and is the easiest to undercount. A reworked Colored Protective Case needs its latch stripped, paint touched in, gasket refitted and retested, and 2.1 of the 4.6 hours go into stripping and rebuilding. At 3 percent of a 500-unit order that is 69 hours, enough to idle a line for two days.

2. Which Document Wins: Drawing, Factory Standard or Contract

Three documents disagree more often than buyers expect: the drawing holds tolerances, the factory standard holds test methods, the contract holds sampling and disposition. Where they clash, the stricter rule governs.

A usable drawing of a Colored Protective Case carries five numbers: cavity size, wall thickness, latch retention, gasket compression, material grade. Remove one and the inspector falls back on feel.

Colored Protective Case: black case angled slightly right, right side wall and lid parting line visible, red latches fore and aft

3. Six Tools, Three Readings on the Line

Six tools cover the schedule, if each reads a defined number at a defined point.

Vernier caliper: wall thickness at three points per side, twelve in all, accepted between 2.85 and 3.15 mm.
Feeler gauge: lid gap, which must not admit a 0.3 mm blade anywhere.
Push-pull gauge: 200 N held for 10 seconds on the latch, with no release and no plastic set.
Tape and level: outline in three directions, then 1.5 mm lid sag maximum under four-high load.
Drop rig: 1.2 m, ten attitudes of six faces, three edges and one corner, then open and inspect.
Salt spray cabinet: 5 percent brine at 35 C for 96 hours, with no red rust on latch or hinge.

Add a scale: a weight deviation over 3 percent usually means the wall was thinned, and weighing checks it faster than twelve caliper readings. Record each reading on the spot in three columns: measured value, judgement line, verdict.

4. Appearance and Colour: Four Judgement Lines

Appearance is where close enough creeps in. Keep four lines for a Colored Protective Case.

Colored Protective Case: black case turned left, left wall and lid step in view, red latches seated, four feet under the base

Colour: ΔE00 within 0.8 batch to batch and within 1.2 of the sealed sample, under diffuse daylight at 30 cm.

Sink: light hollows at rib roots and behind bosses, 0.05 mm maximum.

Flash: 0.2 mm maximum at the parting line, never a continuous sheet, which signals a venting fault.

Mismatch: 0.3 mm maximum between lid and body, past which gasket compression drops under 20 percent and rain enters.

5. Rework, Concession or Rejection: Three Cost Tiers

Disposition turns on one question: functional or cosmetic?

Functional defects, meaning a wall under 2.85 mm, retention below 200 N, a split after drop or rust after salt spray, are reworked or rejected, never conceded. These faults amplify in transit.

Cosmetic defects, meaning colour, sink, flash or mismatch, may go to concession at 6 percent of batch value, provided the functional result is clean.

Rejection applies when two sampled units fail functionally, or any unit shows a through crack. Price the line stop first: at 420 yuan an hour, eight hours is 3,360 yuan, above the concession gap, so rework usually beats rejection.

6. Sampling and Records: Closing the Escape Route

Sample to AQL 1.0 at general level II: a 500-unit batch means 13 pieces, accept on zero, reject on one, drawn from three pallets.

Records must trace to mould and shift: eight columns for batch, mould, machine, material grade, measured wall, colour reading, verdict, inspector.

Keep three samples for 24 months: they settle whether a complaint is a batch fault or a user fault, which a Colored Protective Case colour dispute always becomes.

Conclusion

Acceptance cost for a Colored Protective Case depends on how tightly the judgement lines are written, not on how closely an inspector looks. Rework at 38 yuan, concession at 6 percent, rejection at 24,000 yuan and a line stop at 420 yuan an hour all map to a measurable line. Five drawing numbers, six tools, four cosmetic lines and three tiers turn the argument into a reading.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.