Whats wrong with using a pin-nose-seal if it doesnt shoulder?
Pin-Nose-Seals, also known as metal-to-metal seals, are extremely susceptible to damage, and a single ding on a nose or its seat too small to see under field conditions, can cause leakage, even though extreme care was taken during assembly. Although a ding can be filed down so you cant feel it, the sealing capability cannot be restored in the field, and no adjacent seal as exists in thread seals, is close by to compensate. The most important function for a pin-nose-seal is to reduce the pressure area of a connection to the minimum, which becomes an advantage for such as a flush- joint connections when a 100% pressure rating is required, and when used, threads that seal should be present to back it up. Also, improperly designed pin-nose seals may fail after minimum corrosion.
