Why choose cast floating seals

When selecting floating seals, it is important to consider whether forged steel floating seals or alloy cast iron floating seals are more suitable.

Many buyers are unaware of the differences between the two. The metal seal rings of floating seals can be categorized into alloy cast iron metal seal rings (manufactured through casting) and steel floating seals (produced by forging). The cast iron floating seals exhibit superior quality and sealing performance compared to the forged steel floating seals, albeit at a slightly higher price. This is attributed to several factors.

The upper image depicts the alloy cast iron metal seal ring body, displaying a color as shown in the image, with a dull sound when tapped.

The lower image showcases the forged steel metal seal ring body, appearing in a matte black color, producing a crisp sound when tapped.

In the domestic market for floating seals, the number of manufacturers producing cast floating seals is significantly smaller than the number of manufacturers producing forged floating seals. Additionally, the selling price of alloy cast iron floating seals is higher than that of forged steel floating seals. So what’s the reason of it?

This is because the alloy cast iron material of the metal seal ring body needs to undergo a dual process of annealing and quenching in the manufacturing process, resulting in a longer production cycle compared to forged steel floating seals. Additionally, the production of cast floating seals requires high precision and the processing technology is more challenging at various stages. In contrast, forged steel floating seals typically only utilize high-frequency quenching technology, making the processing from blank to finished product less difficult than that of cast floating seals.

Do you know why high-quality users are willing to pay high prices for alloy cast iron floating seals?

To provide a more intuitive understanding, we conducted an experiment where we selected forged steel and special alloy cast iron floating seals of the same size specifications. We then used a hardness tester to perform indentation hardness tests at multiple positions on the sealing cone surface and the metal seal ring sealing surface.

The experimental results indicate that the hardness of different points on the cast floating seal falls within a specific range, with a very uniform distribution. In contrast, the external surface of the forged floating seal exhibits significantly higher hardness compared to the internal hardness, resulting in a hard exterior and soft core. The hardness values at various sealing surface points vary greatly, leading to low compression resistance during operation, which can result in oil leakage, poor sealing performance, and a shortened lifespan. On the other hand, the cast floating seal is more adaptable and offers better sealing properties.

In conclusion, when choosing floating seals for use in critical applications such as coal winning machine, mining truck, and trench cutter with double wheels, it is recommended to choose high alloy cast iron floating seals.