Investment casting manufacturing process

1、 Make moulds according to different shapes of products.  The mold is divided into up and down concave die, through the car, planing, milling, etching, electric spark and other comprehensive processes to complete.  The shape and size of the pit are consistent with the half of the product.  Because wax mold is mainly used for industrial wax pressing, so the melting point is not high, hardness is not high, the requirements are lower, the price is cheaper, the weight is lighter aluminum alloy materials do the mold.  

2、The use of aluminum alloy mold to produce a large number of industrial wax solid core model.  Under normal circumstances, an industrial wax solid core model can only correspond to a blank product.  

3、The wax mold peripheral allowance for fine repair, after deburring a number of single wax mold stick (also known as group tree) prepared mold head, the mold head is also produced by wax mold industrial wax solid core model.  (Shaped like a tree)  

4、 will have been fixed in the mold head of a number of wax mold coated with industrial glue evenly sprayed on the first layer of fine sand (a refractory sand, high temperature resistance, usually used is silicon sand).  The sand particles are very small and fine, which ensures that the final blank surface is as smooth as possible.  

5、In the set room temperature (or constant temperature) to spray the first layer of fine sand wax mold natural air drying, but can not affect the shape of the internal wax mold changes, natural air drying time depends on the internal complexity of the product itself, the general investment casting first air drying time is about 5-8 hours.  

6、After the first sand spraying and natural air drying, industrial glue (silicon slurry) is continued on the surface of the wax mold, and the second layer of sand is sprayed. The particle size of the second layer of sand is larger and thicker than the first layer of sand before.  After spraying the second layer of sand, let the wax mold dry naturally under the set constant temperature.  

7、 After the second sand blasting and natural air drying, the third sandblasting, the fourth sandblasting and the fifth sandblasting are carried out in sequence.  Requirements: - According to the product surface requirements, volume size, weight and other corresponding adjustment of sandblasting times.  In general, the number of sandblasting is 3-7 times.  - Each sandblasting sand size is different, usually the sand after the process is thicker than the previous process sand, air drying time is not the same.  Generally, the production cycle of sand on a complete wax mold is about 7-15 days.  

8、Will have completed the sand blasting process of wax mold in the baking process, then evenly coated with a layer of white industrial latex (silicon slurry), in order to bond and solidified sand mold, as well as sealing wax mold, to prepare for the next baking process.  At the same time, after the baking process, but also improve the brittleness of the sand, easy to break the sand layer, take out the blank.  

9、The baking process will be fixed on the mold head, and complete sandblasting air drying process of wax mold into the metal closed special oven heating (commonly used is kerosene burning steam furnace).  Because the melting point of industrial wax is not high, the temperature is about 150゜ ゜, wax mold is heated and dissolved to form wax water flowing along the gate, this process is dewaxing.  The wax mold is just an empty shell.  The key to precision casting is this empty shell.  (Generally this wax can be used repeatedly, but these wax must be re-filtered, otherwise the unclean wax will affect the surface quality of the blank, such as: surface sand hole, pitting, but also affect the shrinkage of the investment casting product).  

10、 Baking sand shell to make the waxed sand shell more solid and stable, before pouring stainless steel water, must bake sand shell, usually in the high temperature (temperature about ゜ 1000゜ about) stove baking.  

11、The stainless steel water that has been dissolved into liquid at high temperature is poured into the waxed sand shell. The liquid stainless steel water is filled with the space before the wax molding until it is fully filled, including the middle part of the mold head.  

12、 Because the boiler of dissolved stainless steel will have different ingredients mixed with the material, the factory must test the material percentage.  Then adjust the proportion as needed, such as adding those aspects to achieve the desired effect.  

13、 Liquid stainless steel water cooling after solidification, with the help of mechanical tools or manpower will be the outermost shell of sand broken, exposed solid stainless steel products is the original wax mold shape, that is, the final need for blank.  Then it will be cut one by one, separated and then roughed into a single blank.  

14、 Check the blank: the blank with trachoma and porosity on the surface must be repaired by argon arc welding. If the waste products are serious, they will be returned to the furnace after cleaning.  

15、Cleaning blank: the blank after inspection must go through the cleaning process.  

16、Process other processes until finished products.