For ordinary machining of low strength steel, what is the recommended ratio of soluble oil to water?

The recommended ratio of soluble oil to water for ordinary machining of low-strength steel is typically in the range of 10 to 20 parts of water to one part of soluble oil. This ratio is optimal because it ensures effective lubrication and cooling during the machining process, which helps to reduce wear on cutting tools and enhances the overall surface finish of the machined parts.

When using a ratio within this range, the soluble oil provides a protective film that minimizes friction between the cutting tool and the workpiece, while also aiding in the removal of chips and heat. Maintaining this balance is crucial for both the performance of the machining operation and the longevity of the equipment involved.

In contrast to other options that suggested either narrower or broader ranges, the 10 to 20 ratio aligns with industry standards and empirical practices, making it the most suitable choice for the conditions described.