Why is the cast bronze bushing blank so much larger than the finished product?
Because the copper alloy is rapidly oxidized in contact with air at high temperatures, this thick layer of copper alloy oxide must be removed until it is cut to the size that meets the precision machining. Oxides are mainly produced in the smelting and casting steps, which are also unavoidable in the production and processing of bronze bushings.
- During the smelting process of the copper alloy of the bronze bushing, oxides will always be produced in the contact part between the liquid surface layer and the air in the high-temperature furnace of thousands of degrees. Workers removed it carefully.
- The most important thing is that during the casting process, when the ultra-high temperature copper alloy liquid is poured into the rapidly rotating bronze bushing mold, the outermost layer of copper alloy liquid is completely in contact with the air, which will produce a thick layer of oxides.
- For example, for a 10 cm thick bronze bushing blank, only 1/3 of the blank remains after precision machining; or if a 3 cm thick bronze bushing is required, the blank may be 10 cm thick.
Therefore, the quotation of bronze bushings can not only be based on the material price. Among them, the special requirements of loss, processing, and even chemical properties are important points to test whether the factory is qualified.
We have been in the bronze bushing industry for nearly 30 years, with casting capabilities ranging from 6mm to 5m in diameter. Countless customers have turned to us to buy products because of the inferior materials of their original suppliers, and the quality cannot be guaranteed. We are proud of this.
How to remove dross/impurities inside bronze bushings?
Impurities are absolutely not allowed inside the bronze bushing. If there are impurities, the whole product will be scrapped. We reviewed the entire smelting process many years ago and concluded how to avoid it:
- Increase the melting temperature. If the smelting temperature is too low, the copper alloy material in the electric furnace will not be fully dissolved or even boiled. The gas, impurities, and scum in it cannot be removed in time or even rolled to the surface to volatilize. Once the impurities are deposited into the bronze bushing, the entire product will be scrapped.
- Speed up the casting speed. Too low a casting speed will result in an unqualified shape of the bronze bushing and may also allow impurities to settle inside the bronze bushing. Another point is that some special chemical materials cannot be evenly distributed in the finished product. Eventually, to the scrapping of the entire product.
Why are there fine holes on the surface of the bronze bushing?
When the technology was immature many years ago, we found that the surface of the finished bronze bushing had pores, some as thin as pinholes, and some were completely circular as if a bubble was inside. After rechecking the entire production process, it was found that it was the relationship between air and humidity. Cleverly, pinholes and blowholes never exist at the same time, so we have a solution right away.
- There are pinholes on the surface of the bronze bushing. This is because there is hydrogen in the copper alloy liquid, and by increasing the melting temperature, the hydrogen can be completely evaporated; it should be noted that our factory is located in a subtropical area, the air is humid, and there are long rainy seasons, plum rainy seasons, workshops and Materials need to be kept dry.
- There are bubble holes on the surface of the bronze bushing. This is because there is oxygen in the copper alloy liquid, so it is necessary to add an appropriate amount of deoxidizing material during smelting. It is necessary to ensure that no air bubbles are generated and the chemical properties of the bronze bushing are not affected.
We all ask our customers: What do you value when purchasing? price? quality?
We have achieved results through nearly 30 years of honest cooperation: real price, assured quality, and service that will not be offline. We manufacture bronze bushings to ASTM standards: C83600, C90710, C95400, C95800, C95500, C93800, C94100, C86300, C86400. Provide the inspection certificate, and the quality assurance you need. Hope to have the opportunity to cooperate with you. thanks.
