Abstract: An apparatus and method for spraying solid lubricant to obtain coatings thereof on inner surfaces of an injection sleeve and a spool bushing of a die-casting machine. The die-casting machine further includes a first spraying assembly 1 having nozzles 11 and 12 directed to the injection sleeve 85 and a second spraying assembly 2 having a nozzle 21 directed to the spool bushing 86. The nozzles 11, 12 and 21 are connected to a tank 4 for the solid lubricant. The first and second spray assemblies 1 and 2 are provided with corresponding moving devices 3 and 23 for obtaining a desired movement of the nozzles 11 and 12 and 21, respectively. Nozzle cleaning devices 71 and 72 are provided for cleaning the nozzles 11 and 12 and 21, respectively after the completion of the spraying operation.

Abstract: A method of discriminating the quality of die-cast articles when casting an article by pressurizing and filling a molten metal into a die through an injecting sleeve using an injecting plunger. The method has the steps of measuring at least one of the operational parameters of a die temperature, a gas pressure in a die cavity, a molten metal pressure in a die cavity, an injecting sleeve temperature, an injecting plunger travel speed, and an injection plunger displacement; and discriminating the quality of a die-cast article by comparing the measured parameter value with a reference value determined on the basis of a predetermined interrelationship between the operational parameter and an allowance limit of the amount of a casting defect.

Abstract: A die-casting method in which a lubricant is heated to a temperature higher than a temperature of mold cavity surfaces before molten metal is injected into the mold cavity. The lubricant is heated when the mold cavity is formed by bringing a movable mold into contact with a stationary mold. The heated lubricant is introduced into the mold cavity and applied on the mold cavity surfaces, and the molten metal is then injected into the mold cavity. The molten metal is allowed to solidify in the mold cavity to become a solidified article. A die-casting device for carrying out this method is also provided according to the present invention.

Abstract: A die-casting arrangement which prevents a lubricant from becoming mixed into a die cast article which might cause it to bulge when later heated. The lubricating agent is sprayed over a high-temperature portion of a sprue interconnecting a mold cavity and an injection sleeve in order to partly carbonize the lubricant. The carbonized lubricating agent even if mixed into a die cast article will not expand even when the article is heated thereby preventing bulging of the article.

Abstract: A die-casting arrangement which prevents a lubricant from becoming mixed into a die cast article which might cause it to bulge when later heated. The lubricating agent is sprayed over a high-temperature portion of a sprue interconnecting a mold cavity and an injection sleeve in order to partly carbonize the lubricant. The carbonized lubricating agent even if mixed into a die cast article will not expand even when the article is heated thereby preventing bulging of the article.

Abstract: A die-casting method that eliminates the need to inject insulation. By injecting molten metal sufficiently quickly after injecting tip lubricant, die-cast products may be removed from the mold even without injecting isulation. To this end, a movable die may at least begin moving toward a fixed die before tip lubricant is injected. The tip lubricant may be injected from a molten metal pouring port in a shot sleeve or from the movable die toward the shot sleeve. Tip lubricant which has been introduced into the shot sleeve is conveyed into the die cavity by movement of the molten metal, thus coating the die cavity inner surface.