To demand higher surface processing, according to rough, half of pure, finishing in stages and in rough finish machining can arrange between secondary surface (such as size TouYou hole, bearings lock) processing, mouth slot to make the work have full time distortion, in order to eliminate stress, ensure the precision of the processing.
The connecting rod main processing process analysis:
1.Both ends of the plane processing
The connecting rod surface is connecting rod surface processing and other the positioning standards and connecting rod in some automatic line of automatic conveyer base surface. The plane, and between the two end at both ends and the crankshaft pin hole with each other between the accuracy requirement of the position. The first working procedure linkage processing is processing both ends plane. In size head hole before finishing, often also to two plane this precision.
The connecting rod end processing general use of the grinding process. The connecting rod blank, of the two forging face pressure, fine size precision can reach + 0.15 ~ 0.20 mm +. The purpose is to improve the pure pressure blank precision, reduce surplus, make it no longer after turning, milling rough machining can direct grinding. Grinding way has two kinds:
1).In more than vertical shaft grinding wheel grinding surface grinder bosses on, this is a kind of the most commonly used in the machine tool, the way round the decorated grinding the adjacent at both ends, the connecting rod to end a fixture and small head external circular and big head a profile positioning, grinding, the face of a flip sides placed in another clamping fixture, grinding another end, through two times the installation, and the rotation with two laps, the a flip, finish grinding machine, both sides in a table can install DuoGe fixtures, the loading and discharging the auxiliary time and processing time overlap, so this is a highly efficient processing method. Size of the connecting rod, high class multi-purpose biaxial vertical shaft bosses or more surface grinder, head to the size range of link, used the high vertical five axis frustum surface grinding.
2). Adopts horizontal double grinding wheel to the grinding machine, the grinding and vertical shaft grinding wheel grinding machine more similar, in a large grinding wheel on the drum diameter wheel, equipped with DuoGe fixture, blank in the fixture, both sides to the location of the grinding wheel and the horizontal-axis installed in the two end face grinding workpiece fixture, this kind of means efficiency is very high also, also has the assistant time and the characteristics of the processing time overlap. Since the two end at the same time was grinding, no longer need to turn over face second installation.
2.Body and cover points in the plane of the surface and other processing
The connecting rod in addition to two end other than a plane, including body and cover points and positioning of the face with side, and overall size head of blank connecting rod body cut and cover when cut half surface, mostly in successive broaching machine and cut.
Successive pull with the following features:
1). A and pull cutting. In a large transmission chain, in turn on several clamp, installed with pull cutting through the area, the cut, cut each pull. These fixture type can, and therefore can be different will generally need two sets on broaching machine in the cutting process, complete, through the workpiece was installed in different kinds of jig method in a machine, combination on implementation.
2). In pull no empty cut tool for cutting process loss, and cutting tools motionless, fixture through the pull off the automatic cutting area, with the chain, the lower the expected return on the bed.
3).Mobile time and auxiliary time overlap. Successive pull cutting has the very high productivity, usually per hour for 200-300 pieces, some can reach 700 pieces or more. In addition, it also can pull, processing precision cutting surface stability, dimension tolerance can reach 0.05 mm, the tool life long. The body also can use this method cut cover. Continuous pull cutting method in it is the most widely used in processing connecting rod.