SOP: Dimensional Checking of Glass Containers

GIFSQ — Global Institute for Food Safety & Quality

Principle

Dimensional checking ensures that the bottle will perform satisfactorily during filling, packing and handling. The bottle height is measured with vernier instruments and the diameter is checked with ring gauges against maximum and minimum limits. Deviation often occurs in local areas of the bottle surface that are not fully blown up to the mould or shrink away from it after blowing.

Apparatus required

• Vernier calipers with large enough jaws (for measuring height)
• Vernier height gauge or spring-loaded dial gauge (more convenient for height)
• Ring gauges (for measuring maximum and minimum diameter)

Procedure

Measurement of height

↓

Measure the height using ordinary vernier calipers having large enough jaws, or more conveniently with a vernier height gauge or a spring-loaded dial gauge set to the required height

↓

A go/no-go gauge may be constructed, as in the case of the seam testing gauge for cans

Measurement of diameter

↓

Use a ring gauge for measuring the maximum and minimum diameter

References

Ranganna, S., Handbook of Analysis and Quality Control for Fruit and Vegetable Products, 2nd edition.