Dynatube fittings consist of a threaded male connector, a female shoulder with a machined beam, and a nut (fig. 6-30). Compared to the five components in a standard MS fitting, the three components in a Dynatube fitting are smaller, lighter, and have fewer potential leak paths. Dynatube fittings can be connected to rigid tubing by welding, but internal mechanical swaging with Resistoflex

hand tools is the authorized method for Navy personnel.

The repair methods using Dynatube fittings are discussed in this section and illustrated in figures 6-31 through 6-33.

One method of repairing damaged Dynatube fittings is to use longer length Dynatube fittings. These can be installed in place of damaged fittings on the same tube assembly, as shown in figure 6-31. Dynatube male fittings with minor surface damage such as scratches can be repaired using the Dynatube fitting resurfacing tool, shown in figure 6-32. Do not attempt to repair a damaged female Dynatube fitting. Damaged straight tubing can be repaired by cutting out the damaged section and installing a splice assembly in its place, as shown in figure 6-33.

Resistoflex hand tools are housed in a single carrying case (fig. 6-34). These tools are designed for in-place repairs. Figure 6-35 shows tools assembled

Figure 6-34.Field installation and repair tool kit.



Figure 6-35.Dynatube swaging process.



Figure 6-33.Splice assembly repair.



Figure 6-36.Field installation and repair tool kit.

for swaging process. Some of the tools used to swage fitting are shown in figure 6-36.

Tube expanders are precision swaging tools for expanding hydraulic tubing into serrations of Dynatube fitting sockets. Tube expanders are set to expand tubing to a specific diameter, and must be used only with the tube and wall thickness stated on the tool identification band.

Holding fixture dies support and position Dynatube fittings during swaging. Holding fixture dies have a nest that conforms to the shape and size of the fitting to be used. A male and female set of dies is provided for each basic tube diameter size that corresponds with male or female Dynatube fittings. Holding fixture collars are used to clamp holding fixture dies shut during swaging. The resurfacing tool assembly uses replaceable energy discs in progressively finer grades to remove scratches from the sealing surface of male fittings.