EN ISO 13920-BF provides a range of tolerance classes, each with its own set of specific tolerance values. The tolerance classes are designated by a letter (e.g., f, m, c, or v), which corresponds to a specific level of precision. For example, the "f" class represents a fine tolerance, while the "v" class represents a very coarse tolerance.
Thus, – it likely means: Use ISO 13920 (unspecified class, usually Class D or E) + BF weld prep (ISO 9692-1). en iso 13920-bf
The use of EN ISO 13920-1:2014 provides several benefits, including: EN ISO 13920-BF provides a range of tolerance

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EN ISO 13920-BF provides a range of tolerance classes, each with its own set of specific tolerance values. The tolerance classes are designated by a letter (e.g., f, m, c, or v), which corresponds to a specific level of precision. For example, the "f" class represents a fine tolerance, while the "v" class represents a very coarse tolerance.
Thus, – it likely means: Use ISO 13920 (unspecified class, usually Class D or E) + BF weld prep (ISO 9692-1).
The use of EN ISO 13920-1:2014 provides several benefits, including: