Application of Precision Machining Equipment Crankshaft

XingChang Fan will talk about the development trend of crankshaft manufacturing technology.

1. Casting Technology

(1) Smelting

For the melting of high-grade cast iron, a large-capacity medium-frequency furnace or a variable-frequency medium-frequency furnace will be used for melting, and the composition of molten iron will be detected by a direct-reading spectrometer. Nodular cast iron is treated by subcontract, the new nodulizing agent is developed, and advanced inoculation methods such as stream inoculation, in-mold inoculation, and compound inoculation are adopted. The parameters of the melting process are controlled by a microcomputer and displayed on the screen.

(2) Modeling

Lost Foam Casting will be developed and popularized. In sand casting, no-box injection molding and extrusion molding will be paid attention to and will continue to be popularized and applied in newly built or rebuilt factories. The original high-pressure molding line will continue to be used, and some key components will be improved to realize automatic core assembly and core lowering.

2. Forging Technology

The automatic line with a hot die forging press and electro-hydraulic hammer as the main machine is the development direction of forging crankshaft production. These production lines will generally adopt precision shearing blanking, roll forging (cross wedge rolling) blank making, intermediate frequency induction heating, etc.

3. Mechanical processing technology

Crankshaft rough machining will widely adopt advanced equipment such as numerical control lathes, numerical control internal milling machines, numerical control lathe broaching machines, and the like to carry out numerical control turning, internal milling, and lathe broaching processing on the main shaft journal and the connecting rod journal, so as to effectively reduce the deformation amount of crankshaft processing. Crankshaft finish machining will widely use a CNC-controlled crankshaft grinder to finish grinding its journal.

This grinder will be equipped with an automatic dynamic balancing device for the grinding wheel, an automatic tracking device for the center frame, automatic measurement, an automatic compensation device, automatic dressing of the grinding wheel, constant linear velocity, and other functional requirements to ensure the stability of grinding quality.