Название файла: guidelines_PMKVY.pdf
Размер файла: 552 Килобайт
Количество загрузок: 590
The two properties of hot strength and collapsibility go hand in hand, and one cannot be discussed without the other. The type of core binder is important from the viewpoint of gas-generating properties as well as the strength the binder will develop. Silica sand is readily available, low in cost, and possesses properties that enable it to withstand the effects of molten metals.The primary function of any molding material is to maintain the shape of the casting cavity until the molten metal is poured and until the casting solidifies. This is illustrated in figure 50. The green strength increases as the sand changes from a coarse sand to a fine sand. Such records are useful in locating a pattern for future use.