It is often incorrectly called National pipe Size, due to confusion with National pipe thread.

通常被错误地称为国家标准尺寸，以免与国家标准螺纹尺寸相混淆。

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It is often incorrectly called National pipe Size, due to confusion with National pipe thread.

通常被错误地称为国家标准尺寸，以免与国家标准螺纹尺寸相混淆。

youdao