陕西科技大学：《包装技术基础 Fundamentals of Packaging Technology》课程PPT教学课件（英文版）Lesson 6 Glass Containers 第6课 玻璃容器

Lesson 6 Glass Containers 第6课 玻璃容器 ⚫ Glass Types and General Properties ⚫ Bottle Manufacture ⚫ Bottle Design Features

Lesson 6 Glass Containers 第6课 玻璃容器 ⚫ Glass Types and General Properties ⚫ Bottle Manufacture ⚫ Bottle Design Features

一. Glass Types and General Properties ⚫ Definition and characters- an inorganic substance fused at high temperatures and cooled quickly ⚫ About the principle component -silica (quartz), ⚫ The ingredients of the components and different formulations. ⚫ Other mineral compounds be used to achieve improved properties: decolorizers – to clear; colorants– change the appearance. ⚫ Other glass types used for special packaging purposes. lead compounds, boron compounds, borosilicate glasses. ⚫ The problems of different formulations include soda-lime and regular container glass are mixed when recycling

一. Glass Types and General Properties ⚫ Definition and characters- an inorganic substance fused at high temperatures and cooled quickly ⚫ About the principle component -silica (quartz), ⚫ The ingredients of the components and different formulations. ⚫ Other mineral compounds be used to achieve improved properties: decolorizers – to clear; colorants– change the appearance. ⚫ Other glass types used for special packaging purposes. lead compounds, boron compounds, borosilicate glasses. ⚫ The problems of different formulations include soda-lime and regular container glass are mixed when recycling

一. Glass Types and General Properties Advantages as a packaging material: ⚫ inert to most chemicals ⚫ perfect foods container. ⚫ impermeability ⚫ clarity ⚫ perceived image ⚫ rigidity ⚫ stable at high temperatures Disadvantages : breakability; high weight; high energy costs

一. Glass Types and General Properties Advantages as a packaging material: ⚫ inert to most chemicals ⚫ perfect foods container. ⚫ impermeability ⚫ clarity ⚫ perceived image ⚫ rigidity ⚫ stable at high temperatures Disadvantages : breakability; high weight; high energy costs

二. Bottle Manufacture 1. Blowing the Bottle or Jar ⚫ Process: "blow-and-blow”; "press-and-blow" ⚫ two molds: blank mold forms the neck and the initial shape blow mold produce the final shape ⚫ A blank mold comes in a number of sections: finish section cavity section (made in two halves to allow parison removal) a guide or funnel for inserting the gob a seal for the gob opening once the gob is settled in the mold blowing tubes through the gob and neck openings

二. Bottle Manufacture 1. Blowing the Bottle or Jar ⚫ Process: "blow-and-blow”; "press-and-blow" ⚫ two molds: blank mold forms the neck and the initial shape blow mold produce the final shape ⚫ A blank mold comes in a number of sections: finish section cavity section (made in two halves to allow parison removal) a guide or funnel for inserting the gob a seal for the gob opening once the gob is settled in the mold blowing tubes through the gob and neck openings

二. Bottle Manufacture Figure 6.1 Furnace draw-off orifice and gob shears ⚫ Molten glass flows depending on the bottle size. ⚫ Mechanical shears snip off "gobs" of molten glass. Each makes one container. ⚫ Falling gob is caught by spout and directed to blank molds. ⚫ Mass-production is made up of several individual sections, each is an independent unit holding a set of bottle-making molds. ⚫ Large bottles consists of a blank mold and a blow mold. ⚫ Higher production using double or triple gobs on one machine. two or three blank molds and similar blow molds. Gobs -to form blank mold

二. Bottle Manufacture Figure 6.1 Furnace draw-off orifice and gob shears ⚫ Molten glass flows depending on the bottle size. ⚫ Mechanical shears snip off "gobs" of molten glass. Each makes one container. ⚫ Falling gob is caught by spout and directed to blank molds. ⚫ Mass-production is made up of several individual sections, each is an independent unit holding a set of bottle-making molds. ⚫ Large bottles consists of a blank mold and a blow mold. ⚫ Higher production using double or triple gobs on one machine. two or three blank molds and similar blow molds. Gobs -to form blank mold

二. Bottle Manufacture ⚫ Blow-and-blow process-for narrow-necked bottles ⚫ The two processes differ according to the parison producing. ⚫ Blow-and-blow process: (Figure 6.2): 1. Gob dropped into the blank mold through a funnel-shaped guide (985°C) 2. parison bottomer replaced guide ;air blown into settle mold to force the finish section. At this point the bottle finish is complete. 3. Solid bottom plate replaced parison bottomer ; air is forced to expand the glass upward and form the parison. 4. Parison removed from the blank mold, rotated to a right-side-up orientation for placement into the blow mold. 5. Air forces the glass to conform to the shape of the blow mold. The bottle is cooled to stand without becoming distorted and is then placed on conveyors to the annealing oven

二. Bottle Manufacture ⚫ Blow-and-blow process-for narrow-necked bottles ⚫ The two processes differ according to the parison producing. ⚫ Blow-and-blow process: (Figure 6.2): 1. Gob dropped into the blank mold through a funnel-shaped guide (985°C) 2. parison bottomer replaced guide ;air blown into settle mold to force the finish section. At this point the bottle finish is complete. 3. Solid bottom plate replaced parison bottomer ; air is forced to expand the glass upward and form the parison. 4. Parison removed from the blank mold, rotated to a right-side-up orientation for placement into the blow mold. 5. Air forces the glass to conform to the shape of the blow mold. The bottle is cooled to stand without becoming distorted and is then placed on conveyors to the annealing oven

二. Bottle Manufacture Figure 6.2 Blow-and-blow bottle manufacture

二. Bottle Manufacture Figure 6.2 Blow-and-blow bottle manufacture

二. Bottle Manufacture Figure 6.3 Press and blow forms the parison by mechanical action ⚫ Gob delivery and settle-blow steps are similar to blow-and-blow forming. ⚫ Parison is pressed into shape with a metal plunger rather than blown into shape(Figure 6.3). ⚫ The final blowing step is identical to the blow-and-blow process. ⚫ Used for smaller necked containers. ⚫ Better control of glass distribution press-and-blow process-for wide-mouthed jars

二. Bottle Manufacture Figure 6.3 Press and blow forms the parison by mechanical action ⚫ Gob delivery and settle-blow steps are similar to blow-and-blow forming. ⚫ Parison is pressed into shape with a metal plunger rather than blown into shape(Figure 6.3). ⚫ The final blowing step is identical to the blow-and-blow process. ⚫ Used for smaller necked containers. ⚫ Better control of glass distribution press-and-blow process-for wide-mouthed jars

二. Bottle Manufacture Difference of the two processes ⚫ Blow-and-blow used for narrow-necked bottles. Press-and-blow used to make wide-mouthed jars and for increasingly smaller necked containers. Better control of glass distribution. ⚫ Typical production rates range from 60 to 300 bottles per minute, depending on the number of sections in a machine, the number of gobs being extruded, and the size of the container. ⚫ The blown bottle is removed from the blow mold with takeout tongs and placed on a deadplate to air cool for a few moments before transfer to a conveyor that transports it to the annealing oven

二. Bottle Manufacture Difference of the two processes ⚫ Blow-and-blow used for narrow-necked bottles. Press-and-blow used to make wide-mouthed jars and for increasingly smaller necked containers. Better control of glass distribution. ⚫ Typical production rates range from 60 to 300 bottles per minute, depending on the number of sections in a machine, the number of gobs being extruded, and the size of the container. ⚫ The blown bottle is removed from the blow mold with takeout tongs and placed on a deadplate to air cool for a few moments before transfer to a conveyor that transports it to the annealing oven

二. Bottle Manufacture 2. Annealing ⚫ Purpose-to reduce internal stresses; in annealing oven ⚫ Reasons- Walls are comparatively thick and cooling will not be even. The inner and outer skins of a glass become rigid The still-contracting inner portion build up internal stresses Uneven cooling develop substantial stresses in the glass. ⚫ Bottle passes through an lehr after removal from the blow mold. ⚫ Steps : glassware is carried on a moving belt temperature is raised to about 565°C gradually cooled to room temperature with all internal stresses reduced to safe levels.(about an hour) ⚫ Improperly annealed bottles are fragile and high breakage ⚫ Hot-filling also produce unacceptable breakage levels

二. Bottle Manufacture 2. Annealing ⚫ Purpose-to reduce internal stresses; in annealing oven ⚫ Reasons- Walls are comparatively thick and cooling will not be even. The inner and outer skins of a glass become rigid The still-contracting inner portion build up internal stresses Uneven cooling develop substantial stresses in the glass. ⚫ Bottle passes through an lehr after removal from the blow mold. ⚫ Steps : glassware is carried on a moving belt temperature is raised to about 565°C gradually cooled to room temperature with all internal stresses reduced to safe levels.(about an hour) ⚫ Improperly annealed bottles are fragile and high breakage ⚫ Hot-filling also produce unacceptable breakage levels