Grids continual processing

Wrought lead—calcium—tin alloys contain more tin, have higher mechanical strength, exhibit greater stabiUty, and are more creep resistant than the cast alloys. RoUed lead—calcium—tin alloy strip is used to produce automotive battery grids in a continuous process (13). Table 5 Hsts the mechanical properties of roUed lead—calcium—tin alloys, compared with lead—copper and roUed lead—antimony (6 wt %) alloys. 

Schematics of continuous process for manufacture of plates with expanded grids [99].

A disadvantage of these alloys is their softness. So they cannot be manufactured by the conventional casting process, because they could not be handled in the usual equipment, like pasting machines. Rather they depend on continuous processes that combine grid manufacture with pasting. 

Other continuous grid manufacturing processes. The cross section of a lead-coated copper grid is shown in Figure 6.16. 

From a physical point of view, the finite difference method is mostly based based on the further replacement of a continuous medium by its discrete model. Adopting those ideas, it is natural to require that the principal characteristics of a physical process should be in full force. Such characteristics are certainly conservation laws. Difference schemes, which express various conservation laws on grids, are said to be conservative or divergent. For conservative schemes the relevant conservative laws in the entire grid domain (integral conservative laws) do follow as an algebraic corollary to difference equations. 

Because of this increase in the VOC/NOa ratio as the air mass moves downwind, isopleths appropriate for one portion of an air basin, e.g., the upwind portion, will not necessarily be applicable to other regions, such as the downwind areas. The development of sophisticated grid-based models and their application to entire air basins have allowed modelers to include continuing emissions, transport, and transformation processes (see Section A.3). 

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