Abstract: A method and apparatus for finishing pistons (10) and the like from foundry-turned castings during one clamping operation to provide enhanced manufacturing productivity. Separate boring and turning modules (34, 24) of the apparatus are mounted on a primary base (18) and a grooving module (54) is mounted on a secondary base (72). The modules automatically groove the ring grooves (11), turn the complex shape of the skirt (15) and bore the wrist pin bore (13) through an ordered sequence of manufacturing steps. The piston stock is mounted for rotation on headstock and tailstock assemblies (82, 84). These assemblies are carried on the secondary base (72) which is slidably mounted on the primary base for movement into operative position with respect to the boring and turning modules according to the ordered sequence. The method and system improve piston quality while reducing manufacturing costs including saving factory floor space.

Abstract: A method and apparatus for locating and clamping a piston (10, 110) between headstock and tailstock assemblies (18, 118 and 20, 120) before rotating same about a rotary axis (22, 122) in a machining operation is characterized by an equalizing mechanism or member (50, 150) for equalizing the axial force between a pair of equalizing pins (48, 148) of a first set of axially extending locating pins (46, 48; 146, 148) to thereby create a locating plane on a first surface of the workpiece. The first set of axially extending pins coacts with a second set of axially extending equalizing pins (30, 130) to clamp the workpiece therebetween. The first set of locating pins are located in a housing member (38, 138). The first set of pins also includes two fixed locating pins (48, 148) which contact the outer surface of the piston.

Abstract: A method and apparatus for finishing pistons (10) and the like from foundry-turned castings during one clamping operation provide enhanced manufacturing productivity. Separate boring and turning modules (34, 24) of the apparatus are mounted on a primary base (18) and a grooving module (54) is mounted on a secondary base (72). The modules automatically groove the ring grooves (11), turn the complex shape of the skirt (15) and bore the wrist pin bore (13) through an ordered sequence of manufacturing steps. The piston stock is mounted for rotation on headstock and tailstock assemblies (82, 84). These assemblies are carried on the secondary base (72) which is slidably mounted on the primary base for movement into operative position with respect to the boring and turning modules according to the ordered sequence. The method and system improve piston quality while reducing manufacturing costs including saving factory floor space.