Monobloc containers

Aluminium aerosols are inherently more expensive than tinplate but can be made in one piece with neither side seam nor bottom chime. However, for practical or economic reasons these Monobloc containers are usually restricted to the smaller sizes of aerosol. Larger sizes are produced in two pieces, i.e. with a continuous side wall and a seamed-on base. In the past few years the process of drawing and wall ironing has enabled continuous side wall containers to be produced from both aluminium and tinplate sheet. Unlike two-piece extruded body containers, these containers have no base chime but instead have a seamed-on cone. When two different metals are involved, e.g. aluminium body and tinplate base, additional product compatibility checks must be carried out due to the risk of electrolytic corrosion. Again special coatings are available to inhibit this effect. 

V design and comprises six lead-acid cells in a monobloc container. This battery is compatible with the vehicle electrical system that operates in the voltage range from about 12 to 14 V. Until around 1970, 6-V systems were also in use. In European trucks and buses on the other hand, it is common practice for two, 12-V batteries to be connected in series to achieve a nominal voltage of 24 V. 

Also available in the standard range is the R series of engine-starting standby batteries. These batteries are supplied as single cell containers with capacities up to 384Ah, or as monobloc containers with capacities up to 276 Ah (Table 50.12). 

Capacities up to2152 Ah are available in this range (Table 50.15). Batteries are also available in moulded monobloc containers with capacities up to 250 Ah. 

Aluminum. The majority of aluminum containers are of monobloc (one-piece) constmction, impact extmded from a slug of lubricated aluminum alloy. These containers are widely used for many products and are available in a vast array of heights and diameters. Because these containers lend themselves to additional shaping, many unusual shapes can be found in the marketplace. They may also be coated after the extmsion process. 

Modern hairspray consists of a solution of long, chainlike molecules (called polymers) in a highly volatile solvent. Some brands may also contain oils such as resins and lanolin. In general, a volatile substance is one whose state is unstable at room temperature and may readily change from liquid to gas form. Thus, hairspray is in liquid form within the can, as air pressure has been removed. The can is frequently composed of compounds (e.g., aluminum monobloc or tri-layered steel) that allow for a decreased likeliness of puncturing. Spraying the product results in the deposit of a polymer layer around each hair afrer evaporation of the volatile solvent. The web of polymer molecules on the hairs yields a stiff texture and allows the hairs to resist changing shape. 

The use of Monobloc cans produced by this method is usually restricted to smaller sizes for cost reasons, but in countries where aluminium is cheaper relatively large aerosols are produced. Impact extrusion is also used to produce open-ended cylinders onto which bases are seamed, e.g. general purpose liquid containers and two-piece aerosol cans. In this case a ring slug is used rather than a disc, and the lower end is formed in the shape of the shoulder during the extrusion process, e.g. as for collapsible tubes. 

The above-mentioned traction batteries in grid plate design for smaller vehicles are treated by DIN 43 594. A revised standard will be edited for monobloc batteries in plastic containers (containers as in use for automotive batteries). The pasted plates are thicker the batteries have a special separation between the plates (see Table 2.5). 

The small sealed or semisealed lead-acid cells are available as single 2-V units or as multiple-cell units, usually in 6-V monobloc constructions. They are an outgrowth of the earlier ER-type batteries in which the electrolyte was absorbed in wood pulp separators. The ER-type cells, while spill-proof, contained more electrolyte, did not recombine oxygen on overcharge, and were vented. 

Monobloc batteries, using the cylindrical cell, are produced with two to six cells interconnected in a single plastic container. These 4-, 6-, and 12-V batteries have performance characteristics similar to those of the single cell. The monobloc design is illustrated in Fig. 24.3. A newer type of small cylindrical lead-acid cell made within film electrodes has been introduced. This design has been characterized by Atwater et al. for use in portable electronic and communication applications. 

Container Wood tray holding 2-8 cells Either resin rubber monoblocs or wood trays Either metal containers or wood trays... 

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