Abstract: A cylinder block of an internal combustion engine has a portion between a cylinder block body and a cylinder liner which is sealed against a coolant so as to prevent the coolant from entering a crank case. The cylinder block body is made of a first material. The cylinder liner is cast in the cylinder block body. The cylinder liner is made of a second material different from the first material. The cylinder liner has an engaging portion contacting a portion of the cylinder block body from outside in a radial direction of the cylinder liner.

Abstract: A first cavity is formed between a mold and a core. One of a cylinder block material and a liner material is supplied to the first cavity. A second cavity is formed by expanding or shrinking the core or replacing the core with another core. The other of the cylinder block material and the liner material is supplied to the second cavity. The cylinder block with a liner is produced successively using the same apparatus.

Abstract: A method for producing a cylinder block for an internal combustion engine having a sealing surface on which a gasket is mounted, a number of cylinder bores arranged side by side, each cylinder bore opening to the sealing surface, a water jacket surrounding the cylinder bores, and a cooling passage located between the cylinder bores. A liner assembly is first formed by joining a set of cylinder liners with each other side by side. At least one of the liners has a recess that forms a space located between adjacent cylinder liners when the liners are joined. A cast body having the water jacket is molded by pouring molten metal into a mold after the liner assembly is positioned in the mold. The molten metal is prevented from entering the space during the molding process. The space is communicated with the water jacket to form the cooling passage.

Abstract: A process for casting a pipe such as a delivery pipe with transversal holes, the pipe having an elongate longitudinal hole and at least one pair of transversal holes communicating with the longitudinal hole in a substantially normal direction thereto. The process comprises the steps of positioning a rod-like center pin for forming the longitudinal hole in a predetermined positional relation to a cavity formation surface of a casting die, positioning a pair of mandrel pins for forming the pair of transversal holes such that end faces thereof are in contact with side surfaces of the center pin, and charging molten metal into a die cavity after the center pin and the pair of mandrel pins have been positioned. The molten metal is charged under the condition that the center pin is prevented from deforming by the pair of mandrel pins.

Abstract: A method of manufacturing cylinder blocks. A cylinder block includes cylinder liners, the number of which corresponds to the number of cylinders in the engine, and a block body molded integrally with and about the cylinder liners. A liner assembly is formed by aligning cylinders in a single row and connecting the adjacent cylinder liners. A variable section provided between each pair of cylinders enables the distance between the axes of the outer cylindrical surface of each cylinder liner to be varied. The block body is molded by first arranging the liner assembly in a mold. Molten metal is then charged into the mold. When the metal solidifies, the block body is formed encompassing the liner assembly. A reference point on the block body is used to machine the inner cylindrical surfaces and form the cylinder bores.

Abstract: A method for coating a die surface with a foamed release agent is disclosed. The release agent is foamed outside a die and then is supplied to a die cavity. Alternatively, liquid release agent is supplied to the die cavity and then is foamed inside the die. Excess foamed release agent is removed from the die before molten metal is supplied to the cavity. Alternatively, the foamed release agent is left in the cavity, and molten metal is supplied to the cavity. The release agent is foamed through mechanical agitation, bubbling, or by gas released from the release agent when heated.

Abstract: A pressure casting method is disclosed, which permits sufficient pressurizing effect to be obtained for the entire molten metal by varying the speed of advancement of a pressurizing pin according to the state of solidification of the molten metal during pressurizing. In pressure casting using a pressure casting apparatus, while charged molten metal is solidified, it is pressurized by causing advancement of the pressurizing pin into a cavity of the die. During this time, the reaction force received by the pressurizing pin from the molten metal is measured by a pressure sensor, and the speed of advancement of the pressurizing pin is varied through control of the opening degree of a flow control valve according to the measured reaction force. While the reaction force during the progress of solidification of molten metal is high, the flow control valve is controlled to a high opening degree to provide for a high speed of advancement of the pressurizing pin so as to apply a high pressurizing force.

Abstract: The disclosed method of controlling a pressurizing pin, which serves to replenish for the necessary locality with molten metal during solidification of molten metal charged in the cavity, features that the operation of the molten metal replenishment by the pressurizing pin is caused when it is detected that the volume of non-solidified metal has become less than the volume effective for obtaining a molten metal replenishment effect. It is thus possible to obtain efficient replenishment for the necessary locality with molten metal by using a pressurizing pin which is limited in size and stroke.