包装盒专业英语5

Three-Piece Steel Cans
Figure 5.7 The double seam is a critical can component. Every angle, radius, and dimension must be correct to ensure a hermetic seal
Lesson 5
Metal Containers
第5课 金属容器 课
Background
Steel is one of the older packaging materials. - Originally used for round, square, and rectangular boxes and canisters. - The old-fashioned appearance of a fabricated metal box is effectively used to create nostalgia for specialty and gift-type containers. - Sanitary food can, hand-soldered cylindrical metal cans started in the early l800s. - Metal cans’ advantages:
Common Metal Container Shapes
Three-piece steel sanitary food cans. ·Aerosol cans, made by two methods: (1) Three-piece steel cans with a welded body and two ends, and (2) one-piece, impact-extruded aluminum cans necked-in to accept the valve cup. ·Steel or aluminum two-piece drawn-and-ironed beverage cans. ·Two-piece steel or aluminum cans by drawing or by draw and redraw. Full-opening, ring pull-top cans Double-seamed, conventional-top cans ·Cans with hinged lids, usually steel
Three-Piece Steel Cans
Figure 5.5 Typical can-end embossing pattern
Threigure 5.6 Double-seaming is the attachment of the can end to the body. It involves two curling steps.
Common Metal Container Shapes
Figure 5.2 Examples of specialized can shapes
Three-Piece Steel Cans
Steel three-piece can bodies can be mechanically seamed, bonded with adhesive, welded, or soldered (Figure 5.3). - Aluminum cannot be soldered and cannot be welded economically. - Welded sanitary three-piece can bodies are therefore made exclusively of steel. - Mechanical seaming or clinching is used only for containers intended for dry product
Three-Piece Steel Cans
Figure 5.4 The can-welding process
Three-Piece Steel Cans
Sidewall beading: requires more material reduces top-to-bottom compression strength complicates labeling - Can ends intended for thermal processing and a series of circular expansion panels (Figure 5.5). This allows for movement of the end panels so that the contents are able to expand and contract without bulging or otherwise distorting the can. - Can-end compound applied around the perimeter curl as a caulk or sealant (Figures 5.6 and 5.7).
Two-Piece Cans
Draw ·Draw and redraw (DRD) ·Draw and iron (D&I ) Draw Process: Shallow-profile cans（whose height is less than their diameter）can be drawn directly from a circular metal blank. The process is sometimes referred to as "shallow draw." Blanks for drawn cans may be decorated prior to drawing (Figure 5.8)
Three-Piece Steel Cans
Process: （Notes: Soudronic-the global leader for resistance and laser welding systems and key production systems for the metal packaging industry (3-piece cans, industrial packaging) body sheet - a tube with a slight overlap - passing between electrodes - an electrical current heats and fuses the metal (Figure 5.4). Welded seam: about 30% thicker than the two base metal sheets. - Sanitary food cans and bead: to improve resistance to collapse (preventing collapse during pressure differentials encountered during retorting and enables the can to withstand an internal vacuum).
Three-Piece Steel Cans
Figure 5.3 Mechanical, welded, and adhesive-bonded side seams for three-piece cans
Three-Piece Steel Cans
Adhesive bonding, or cementing, uses a thermoplastic adhesive extruded onto a hot can blank. Being an attractive body-assembly method for not being subjected to thermal processing having full wraparound lithography i.e.,three-piece beverage containers ,some frozen juice concentrate and paint cans - Soldered a can, (solders : 97.5% lead and 2.5% tin). Lead extraction by food products and a potential problem with soldered seams Being no longer permitted for food in North America - Welded cans, (strong and eliminate potential lead hazards).
Background
Figure 5.1 Three-piece (left) and two-piece(right) can construction
Background
Shallow drawn containers with friction or slip covers - Two-piece shallow drawn cans with double-seamed (folded) ends - Two-piece cans (Figure 5.1). reduced metal usage improved appearance elimination of a possible leakage location more elaborate tooling required - Deeper draws and multiple draws and draw-and-iron process -Impact-extrusion: tin, lead, and Al; collapsible tubes (nearly Al); heavier gauge aluminum extrusions used for pressurized aerosol containers