CFS is one of the largest stainless steel foundries in China and uses the lost wax method for stainless steel castings. By means of this method, stainless steel investment castings can be produced with high dimensional accuracy and complex shapes. Besides that, it provides the engineer great freedom in product design and material choice. Your specific wishes and demands can be incorporated into the castings. CFS acts as a custom stainless steel casting supplier and exporter with the goal of attaining good quality products for our customers. Our company is the most reliable manufacturer in stainless steel lost wax casting!
Stainless Steel Lost Wax Casting Process
Step 1: Mould Making
The mould used for stainless steel lost wax casting is mainly designed for injecting wax patterns, which are the same dimensions as final stainless steel castings. To ensure the quality of wax patterns, the mould must have high dimensional accuracy and small surface roughness value. Normally, stainless steel casting companies choose aluminum alloy as the mold material. Compared to other suppliers, CFS foundry selects aviation aluminum as the mould material, while other stainless steel casting factories just use normal aluminum to save cost.
Step 2: Wax Pattern Injection
Press the treated wax paste into the mold cavity, take it out after the ice water is condensed by the ice water machine, put it into the pool for a period of time, and get a single wax pattern after dressing and inspection. Wax pattern can be understood as a die cast part.
Step 3: Wax Pattern Reparing
The quality of wax patterns will directly determine the quality of final stainless steel castings. So, the wax patterns workshop needs to controlled with constant temperature, minimize the deformation of wax pattern. Meanwhile, inspect the surface quality of each wax pattern, for those wax patterns with burrs, flash and parting line, they need to be repaired.
Step 4: Tree Assembly
After wax pattern repairing, to improve productivity of qualified wax patterns, a single wax pattern is fused and welded on the pre-made casting system to form a wax pattern assembly. Generally, 2 ~ 80 wax patterns can be welded on one wax module. The tree-forming scheme determines the yield of products and the utilization rate of molten stainless steel. The tree-forming scheme should be carefully considered when designing, and it should be also considered whether the tree-forming scheme is convenient for the recovery and reuse of wax should.
Step 5: Wax Pattern Clearing
After standing for more than 45min, the wax modules behind group trees can be cleaned. Before making shells and hanging slurry, the wax modules after group number must be cleaned to remove wax crumbs and grease on the surface, and improve the adhesion of making shells. Immerse the module in cleaning fluid and reciprocate three times, about 4s in total. After taking out, blow dry the module with compressed air, and then make shell by sizing.
Step 6: Shell Making
After the coating wax patterns, put into shell making shop to dry. The surface layer was dried naturally, while the transition layer and back layer are dried by rotary air drying to speed up the drying. The coating was repeated for 5 ~ 7 times (5 ~ 6 layers for small stainless steel castings and 6 ~ 9 layers for large stainless steel castings). Surface layer with fine sand, transition layer sand slightly coarse, after several layers of sand is thicker), until forming 7 ~ 15mm hard shell, which has enough strength.
Step 7: Dewaxing and Wax Treatment
The shell backwards into the steam dewaxing axe, melt wax patterns, and outflow from the bottom of the shell. By the water separator separation, the liquid wax can be recyclable. 12 hours later, wax liquid through a filter will be included in the static barrels 6 ~ 8 hours, finally wax liquid into the insulation heat preservation box for second use.
Step 8: Shell Roasting, Pouring & Clearing
Before pouring, the shell after wax removal should be roasted. The shell should be roasted for 50 minutes in an oil furnace or electric furnace at 1100℃. The main purpose is to remove the residual wax liquid after wax removal, and improve the strength and permeability of the shell, so as to prevent deformation or rupture of the shell during pouring. Another extremely important factor is to reduce the temperature difference between the castable liquid stainless steel and the shell to reduce the shrinkage of the workpiece. When the heat preservation of molten steel is stable and can be poured, the shell which reaches the roasting time in the roasting furnace can be poured. After the casting condenses, the shell is destroyed and the pouring system is removed. Finally, the burr is cleaned and shot blasting is carried out to obtain the target cast stainless steel parts. The surface of stainless steel lost wax castings should be treated by pickling and passivation.
Benefits of Using Stainless Steel Lost Wax Casting
Intricate detail: Stainless steel lost wax casting allows the production of parts with complex geometric shapes and parts bearing ornate decorative details.
Minimal machining: Stainless steel components obtained through lost wax investment casting typically don’t require extensive machining. Both the precision casting in specific, accurate dimensions and the close tolerances achieved reduce the need for labor-intensive machine modifications during finishing.
Excellent surface finishing: Stainless steel lost wax casting typically displays limited metal burrs and other unwanted excess metal protrusions along flash and parting lines. They also boast an excellent exterior quality following finishing.
High strength: This method of production permits the creation of high-strength component parts, which proves especially useful in the creation of some machine components.
Versatility: Lost wax casting can be used to produce almost any grade of stainless steels, including duplex stainless steel. It can produce multiple detailed parts for high volume manufacturing and at the same time permits the flexibility of producing one part at a time using “one pattern creates one part” system. However, because of the relatively high tooling costs involved in creating the molds, stainless steel lost wax casting is usually employed in comparatively large production runs.
CONTACT CFS FOUNDRY
For any inquiry on stainless steel lost wax casting, contact us via email@example.com or call us directly. We welcome your inquiries.