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Guide to Vacuum Buttons and Container Sealing Study Guide

Learn about the critical role of vacuum buttons in ensuring hermetic seals in steel containers. This guide covers their design, the importance of minimum vacuum requirements, and how closure size impacts vacuum capacity. Includes a worked example for selecting the appropriate closure size based on required vacuum levels, essential for quality control and packaging engineers in the food safety and shelf-life industry.

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Types and Functionality of Closures

Steel Closures for PET Bottles

Steel closures for PET bottles range from 63 to 82 millimeters and feature more lugs to spread force because PET deforms during processing.

  • Steel closures
  • PET bottles
  • Lug count
  • Force distribution
  • PET deformation

Steel Lug and Glass Neck Finishes

Glass Packaging Institute standards manage finished drawings for steel closures and glass finishes to ensure closure suppliers can be interchanged.

  • Glass Packaging Institute
  • finish standards
  • finished drawings
  • closure suppliers
  • finish
  • threads
  • lugs
  • top ceiling surface
  • TSS
  • mold seam
  • blow mold

PT Closures and Plasticol Processing

Plasticol wraps around the outside of a PT closure and softens during a retort process to form thread impressions.

  • PT closures
  • Plasticol
  • Retort process
  • Thread impressions
  • Lug closure

P-T Section and Functionality

A cross-section of a P-T closure illustrates how glass, gasket, metal, and container body layers function to create a seal.

  • P-T closure
  • Cross-section of closure
  • Glass
  • Gasket
  • Metal
  • Container Body
  • Sealing

Steel Closure Components and Vacuum Requirements

Introduction to Steel Closure Components

This lesson covers steel closure components including lugs, plastisol gasket material, indicating buttons, and skirt heights.

  • lugs
  • plastisol gasket material
  • tamper indicating button
  • skirt
  • regular height closures
  • deep height closures
  • closure sizes

Elevation and Temperature Effects on Vacuum

This video explains how elevation and temperature affect the vacuum for steel closures measured in inches of mercury.

  • vacuum
  • inches of mercury
  • elevation
  • temperature
  • steel closures

Temperature Effects on Vacuum Requirements

Heat in the package changes vacuum requirements.

  • temperature
  • heat in the package
  • vacuum requirements

Steel Closures Vacuum and Button Temper

Temper indication ensures buttons stay down despite losing vacuum when increasing elevation.

  • temper indication
  • vacuum loss
  • elevation increase
  • button movement

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