ISO 9057:1991

Overview

ISO 9057:1991 - Glass containers: 28 mm tamper-evident finish for pressurized liquids - Dimensions specifies the dimensional requirements for a 28 mm tamper‑evident glass container finish intended for pressurized liquids. The standard defines the geometric features shown in figure 1 (dimensions in millimetres) and notes that all untoleranced dimensions are nominal. It is intended to ensure reliable sealing and compatibility with tamper‑evident closures for pressurized products.

Key topics and technical requirements

• Scope: Dimensions of the 28 mm tamper‑evident finish for glass containers used with pressurized liquids.
• Normative reference: Vocabulary and related definitions follow ISO 7348:1991.
• Tamper‑evident finish definition: A finish designed to accept a closure that must be snapped before opening.
• Dimensional control: All critical dimensions are given in figure 1; untoleranced dimensions are nominal and dimensions are expressed in millimetres.
• Material/finish integrity: The glass wall thickness through the full depth of the finish must be adequate to withstand normal handling; the finish must be free from cracks likely to impair sealing performance.
• Figure 1 annotations (selection of explicit notes in the standard):
  • Entrance bore: specified as 18.1 mm ±1 mm over a specific depth from 1.5 mm to 3 mm from the top.
  • Cutter diameter: specified as 12.5 mm.
  • For best sealing, the finish should be round and diameters close to nominal; the mean of d3 max and d3 min should approximate d3 nominal.
  • Thread/pitch conversion note: a pitch of 8 threads per inch is equivalent to 3.175 mm.
  • Several maximum radii and form features are detailed in the figure (e.g., R 0.65 max, R 0.8 max) to control sealing geometry.

Applications and users

• Primary users:
  • Glass container manufacturers (tooling and finish design)
  • Closure designers and closure manufacturers (tamper‑evident closures for pressurized liquids)
  • Beverage and pharmaceutical bottlers of carbonated or pressurised products
  • Quality assurance and inspection teams (incoming inspection and process control)
  • Standards and regulatory auditors ensuring packaging integrity
• Practical uses:
  • Designing and tooling moulds/finish press equipment for 28 mm tamper‑evident necks
  • Verifying closure-fit and sealing performance under pressure
  • Establishing inspection criteria and acceptance limits for production runs
  • Ensuring interchangeability of closures and glass finishes across suppliers

Related standards

• ISO 7348:1991 - Glass containers - Manufacture - Vocabulary (normative reference cited by ISO 9057:1991)

Keywords: ISO 9057:1991, glass containers, 28 mm tamper‑evident finish, pressurized liquids, finish dimensions, tamper‑evident closure, glass bottle neck dimensions, ISO 7348.