Nordson MEDICAL offers five series (X, K, B, C, D) of tube connectors with threads. Available threads include 10-32 UNF, ¼ - 28 UNF, 1/16 - 27 NPT, 1/8 - 27 NPT and 5 x .8 and 6 x 1 metric sizes.
The "X" Thread
Nordson MEDICAL X Series components have a tapered 10-32 thread that functions like a pipe thread. In comparison to standard 10-32 UNF threaded fittings, the tapered design works better with oversized ports and ports which are not perpendicular to the face of the component.
The 120 degree chamfer under the hex provides a seal when the fitting is tightened into a port with a countersink as shown below. It also seals on the thread due to interference on the pitch diameter. When using an elbow or tee, the tapered thread tightens radially and facilitates directional alignment of the barb.
Other Thread Series
Our K, B, C and D Series fittings, designed for use with 10-32 UNF ports, are straight-threaded components. These fittings seal against the 120 degree chamfer under the hex on the fitting, and do not tighten radially as they are assembled. Our S Series fittings are straight threaded components for 1/4-28 UNF ports, our M5 Series are for M5 x .8 ports and our M6 Series are for M6 x 1 ports.
Part numbers for fittings with pipe threads are easy to understand. Those for use with 1/16-27 NPT ports have part numbers prefixed with 16; those for 1/8-27 NPT ports have part numbers prefixed with 18; and those for 1/4-18 NPT ports have part numbers prefixed with 14.
The features shown here must be incorporated into the port when using our B, C, D, X, K, S, M5 and M6 Series fittings (see chart below). Failure to do so will jeopardize the performance of the seal between the fitting and port. For applications in which this seal is highly critical, we recommend that you contact a sealant specialist.