Design of impeller blade shape with three yuan flow theory generally for the space curved surface, the vane and the impeller machining molding is the key of the manufacture, is also the difficulty. For three yuan impeller, there are two main types of commonly used processing methods:
: 1) the three body welding form that is roulette, blades, wheel cover, respectively, for processing. This processing method of equipment requirements is simpler, wheel, wheel cover only need car appearance is enough. Blade processing to some trouble, the first to use three coordinate milling machine tool blade mould, then good material of blade under heat treatment, pressed by the blade shape required. The final will be blade welding on the wheel, the wheel cover again good welding. So need equipment is about three coordinate milling machine, hydraulic press, heat treatment furnace and some other conventional equipment, the investment is lower, more suited to do.
2) overall milling: namely roulette with blade is the use of multi-axis device for integral milling and get one and a half open impeller. To avoid interference, the current international for the machining of the impeller are mostly using five coordinate machining centers. A probably from several million to tens of millions of more than five coordinate equipment, the cost is very high. At 600 mm impeller machining as an example, the domestic five-axis bed to about 3.5 million yuan, import five-axis bed it's about 4.8 million yuan, by four coordinate machine rotating table tilted ternary impeller of four coordinates integral milling, if blade consistency is larger, interference problem in four coordinates is inevitable. Four coordinates of equipment is relatively cheap, probably more than 100 yuan.