Is it acceptable practice to pull a line tight using a B nut?

It is not considered acceptable practice to pull a line tight using a B nut because this can compromise the integrity of the connection. B nuts are designed to secure a fitting to a line by allowing for a proper seal between them. When excessive force is applied to tighten a B nut in an attempt to pull a line tight, it can lead to deformation or damage to the fitting or line. This can create leak points and fail to maintain a proper, safe connection.

Moreover, the connection integrity relies on the correct torque specifications, which are established by the manufacturer. Over-tightening or improperly using a B nut can lead to joint failure or other mechanical issues, which can pose safety hazards in a system.

The other options highlight situations where some may think pulling tight could be allowed, but such practices would still ignore the fundamental principles of fluid dynamics and integrity of fittings in a system meant to operate under pressure. Proper installation practices focus on ensuring that connections are secure without overly relying on brute force.