Precision casting is a special kind of casting. Parts obtained in this way usually do not require machining. Investment casting, pressure casting, etc. One of the casting materials is aluminum, stainless steel, titanium, titanium alloy and copper. Significantly save the cost of machined parts.
Precision casting is a casting method relative to the traditional casting process. A relatively accurate shape and high casting accuracy are achieved. The more commonly used methods are: First, design and manufacture molds according to product requirements (very low or no residuals), and use casting method to cast wax to obtain the original wax mold increment. Repeat the coating and sanding process with a wax pattern to cure and dry the shell. The internal wax mold melts and removes the wax to form a cavity. Fire cannonballs to gain enough strength. Metal materials required for casting. After the shell is out, fine sand is processed to obtain a high-precision finished product. Heat treatment and cold processing are carried out according to product requirements.
Investment casting process design
Similar to the typical casting process design, the tasks of investment casting precision casting process design are as follows:
- (1) Machinability analysis of casting structure.
- (2) Choose a reasonable process plan, determine the relevant casting process parameters, and make casting drawings on this basis.
- (3) Design and determine the gating system of the modular structure.
Combining the above three aspects, the main basis is still the basic principles of the general casting process. Especially when determining the process planning and process parameters (casting fillet, mode tilt, machining tolerance, process ribs, etc.). Except for some data, the design principle is the same as sand casting, because the process characteristics of investment casting are slightly different.
- -Pressed wax (spark wax)
- -Wax repair
- -Wax inspection
- -Group tree (wax model tree)
- -Shell (dyed, polished, sizing, and finally air-dried)
- -Dewaxing (steam)
- -Shell roast-chemical analysis
- -Pouring (molten steel is cast in the mold shell)
- -Vibration firing
- -Separation of casting rod
- -Broken gate
- -Initial inspection (blank inspection)
- -Shot blasting
- -Product testing
The manufacturing process of precision castings can be roughly divided into wax, shell, pouring, post-processing and inspection.
The waxing machine includes waxing, waxing and grouping.
The shell contains hanging sand, hanging slurry and air-drying.
Pouring includes roasting, chemical analysis (spectral analysis), casting, shell, gate and gate shaking.
Post-treatment includes sandblasting, shot blasting, correction and pickling.
Inspection includes wax quality inspection, initial inspection, intermediate inspection and final product inspection.