Custom investment casting rope suspension part solutions
1. Analyze the drawings
A new project was entrusted to us by a German client, which required us to develop a rope suspension component. The complete set of this product is depicted in the first and second picture. Its assembly diagram in the third picture, showed how the various parts fit together, offering insights into the product's structural design and the assembly process.
In addition to the rope-suspension part, we also needed to develop certain plates specifically designed to securely fix the lift guide rails. These plates play a crucial role in ensuring the stability and proper alignment of the lift guide rails during operation.
2. Sampling and testing
The housing, wedge, and plates were all casted by the water glass casting process. The overall structure of these parts may not be very complex, but the customer had set relatively high standards for the chemical composition of materials and physical strength requirements, which ensure the products withstand the mechanical stresses and environmental conditions in actual lift applications.
These samples were made according to the customer-provided drawing and submitted to the Ningbo Quality and Technical Supervision Bureau for a series of tests. A chemical material element report was given to us, which shows the chemical composition and physical properties of the materials from the teat bar. This report served as a fundamental document for evaluating the product's compliance with relevant standards.
Tests on the tensile strength, yield strength, and impact resistance of the samples were carried out. The test bars were examined to determine their mechanical properties. The impact test, simulated the forces that the product might endure in real-world scenarios. Moreover, we took the initiative to conduct internal inspections on the products. By cutting the product, we checked for the presence of sand holes inside. This additional inspection step was crucial for ensuring the integrity and quality of the products.
3. Make mass production
After all tests met customer requirements, mass production will be carried out immediately. The pattern (a replica of the final product) is typically made from wax, as the picture showed. The wax melting point is usually between 40~90℃, which is much lower than the casting temperature of metal. The wax model will completely melt and flow out at high temperature and not leave solids, ensuring that the cavity is clean and free of impurities. Wax is cheap, and the melted wax during the dewaxing process can be recycled and reused, reducing production costs.
Then produced multiple identical wax patterns by injection molding.
The wax tree is dipped into a water glass slurry, it is then dusted with a coarse refractory powder (e.g., silica sand) to build a thick, durable outer layer.
This dipping and dusting process is repeated 4-8 times to create multiple layers, forming a shell around the wax patterns. Each layer is allowed to dry and harden before the next is applied. The shell is heated in a kiln at temperatures between 600–1,000°C.The wax melts and flows out of the shell through small vents, leaving a hollow cavity that matches the shape of the original pattern. Then molten metal (e.g., bronze, stainless steel, gold, or aluminum) is poured into the shell. The metal is allowed to cool and solidify completely.
The shell is mechanically broken to reveal the solidified metal casting, and metal tree is cut off from the casting using saws, grinders, or thermal cutting (e.g., plasma torches).
The casting parts are cleaned (e.g., shot blasting to remove surface defects).
4. Packing and Shipment
Finally, we checked the parts well and packed them in cartons, sticked the shipping marks, laid the cartons on pallets and tied them up with strips. Then the pallets were loaded into the container.
Conclusion
This project was finished successfully and the customer was very satisfied. We conducted multiple tests and strictly controlled the product quality in this project, it is not only about satisfying customers, is also about our attitude towards making products. The test bar is needed in the future project to make sure the products are qualified.