Aftertreatment system with tube assembly for pressure sensing

A tube assembly for pressure sensing, the pressure sensing tube assembly comprising:

• a fitting assembly comprising:
• a fitting body comprising a fitting body aperture, an upward-facing surface, and a downward-facing surface, and
• a fitting tube extending from the downward-facing surface, the fitting tube comprising a fitting tube aperture at an inner end of the fitting tube, the inner end distal the fitting body;
• a coupling tube comprising a flared end;
• and
• a nut disposed between the coupling tube and the fitting body, the nut configured to be threadably coupled to the fitting body so as to compress the flared end against the fitting body.

A fitting assembly for a tube assembly for pressure sensing, the fitting comprising:

• a fitting body comprising:
• a fitting body aperture that is not threaded,
• an upward-facing surface,
• a downward-facing surface, and
• an inner surface comprising a fitting threaded portion;
• a fitting tube extending from the downward-facing surface of the fitting body, the fitting tube comprising a fitting tube aperture at an inner end of the fitting tube, the inner end distal the fitting body;
• and
• a nut comprising:
• a nut insert portion comprising a nut threaded portion that is configured to be threadably coupled to the fitting threaded portion, and
• a nut aperture that is not threaded and is configured to be aligned with the fitting body aperture when the nut threaded portion is threadably coupled to the fitting threaded portion.