I. Main Problems Identified

1. Lack of Mold Number Identification Points

The bottle currently has no mold number identification point. When a quality problem occurs, it is therefore not possible to use the automated inspection and sorting system to identify and sort bottles according to their mold numbers.

Manual identification of the mold number on the bottle base at the lamp inspection station is not practical. This also increases the risk of missing defective bottles during inspection.

Recommended Solution

It is recommended to add a mold number identification point to the bottle base.

The photo-integrated inspection machine can be used to identify the mold number identification point and automatically reject bottles with defects.

With this function, lamp inspectors can focus primarily on visual appearance defects, helping reduce the risk of missed defects.

II. Key Quality Control Points During Inspection

1. Bottle Arrangement and Spraying

The arrangement of bottles on the mesh conveyor directly affects spraying quality. For flat bottles in particular, the bottles must be arranged neatly and consistently.

Only when the bottles are properly aligned can spraying be controlled to prevent the coating from reaching the bottle mouth and ensure uniform absorption of the coating liquid by the bottle body.

Proper bottle arrangement also helps prevent ink marks and scratches during transportation and protects the bottle surface.

If excessive numbers of bottles are tipped over or improperly arranged, the affected bottles can only be scrapped. The production team shall communicate and make timely adjustments when such problems occur.

2. Concave or Uneven Body in the Label Area

For flat bottles, strict attention must be paid to bottle body dimensions.

The label area must not have recesses, bulges, or uneven surfaces, as these conditions may affect the labeling process.

Three points on the bottle body — upper, middle, and lower — shall be inspected to ensure that the body dimensions remain within the specified range and to control bottles with concave body deformation.

Quality inspectors shall check the bottle body dimensions once every hour.

3. Bottom Deviation

The bottle base must not be uneven, patterned, or wavy.

A bottom deviation exceeding the specified 1:1.5 ratio is unacceptable. Such bottles shall be classified as non-conforming products and scrapped.

The bottle base requirement of 3 mm or above shall be treated as an acceptable product standard.

4. Production Weight Control

The target bottle weight shall be determined according to the drawing, nominal capacity, and specified liquid level.

Upper and lower weight control limits shall be established accordingly.

Since slight deviations may occur in actual bottle weight, the target weight shall be adjusted according to the actual glass density.

The online inspection data for bottle weight, capacity, liquid level, and other dimensional parameters shall be checked for each production shift every day.

An independent measurement shall also be performed once a day to verify the inspection results and prevent inaccurate or falsified inspection data from affecting product quality.

5. Packaging

Finished-product pallets must be stacked neatly and must not be tilted.

If an uneven or tilted pallet is found, the cause shall be investigated.

Particular attention shall be paid to whether the supporting backboard has become deformed or whether the partition boards were incorrectly positioned during manual palletizing.

The problem shall be identified and communicated to the production supervisor for timely corrective action.

6. Pallets Held for Pending Inspection

Because product quality cannot be continuously tracked during the middle and night shifts, finished-product pallets from these shifts shall be retained for pending inspection.

One pallet shall be retained for inspection for every two pallets produced.

The held pallets shall be retained from the time the products leave the factory until the retained-pallet inspection is completed after the products enter the factory on the following day.

III.  Issues with Machine Inspection Functions

1. Testing Machine

Detect cracked threads, cracked base openings, cracked necks, chipped mouths, mouth sealing performance and mouth dimensional measurements.

2. Photo-Integrated Machine

Detect visual defects including grit particles, bubbles, material depressions, cold cracks, material folds, large-area body cracks and metallic inclusions.

IV. Inventory and Packaging Management

The integrity of finished products in inventory must be properly maintained.

After sampling and inspection of the pallets held for pending inspection, there is no need to damage or unnecessarily open the packaging of other inventory products.

If a problem is found on a pallet held for inspection, strict sampling inspection shall be carried out on the corresponding inventory products according to the relevant pallet number.

Unless there is another specific reason, the outer packaging of inventory products shall be kept intact.

Intact packaging provides better stability during transportation and helps prevent pallet collapse.

The following conditions shall also be monitored:

• Whether inventory pallets are stacked neatly
• Whether the storage location is suitable
• Whether external weather conditions may affect the stored products

V. Color Control

At the beginning of production, the production color shall be compared with the color of the trial-production samples.

After production starts, one finished bottle shall be retained each day as a color reference sample for comparison with the following day's production.

If any color variation is identified, it shall be reported promptly and the production parameters shall be adjusted accordingly.

A higher proportion of re-fed glass material generally results in better product color.

Overall Production Inspection Workflow

During production, the following inspection and control points shall be followed:

Ensure bottles are arranged neatly on the conveyor
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Ensure spraying does not reach the bottle mouth
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Check bottle surfaces for ink marks
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Check the operating condition of the photo-integrated inspection machine
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Confirm adequate staffing at the lamp inspection station
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Check online inspection for any missed defects
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Check palletizing quality and pallet stability
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Sample and inspect pallets held for pending inspection
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Check inventory storage conditions
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Once production is stable, measure and verify all relevant specifications