crimping, interconnecting cables, harnesses, and wiring - NASA

NASA-STD-8739.4 with Change 6Figure 9-12. Plastic Strap Orientation9.7 Metal Braid ShieldingMetal braid shielding can either be woven directly over a core or obtained in prebraided formand installed by sliding it over the wire bundle. To prevent potential damage (cold flow) of theunderlying wire insulation, a separator (e.g., a tape) shall be applied over the wire bundle to givethe wire continuous protection (Requirement). Prewoven braiding shall be tightened down tocontact the wire bundle (Requirement). Braids shall be terminated as specified by theengineering documentation (Requirement). Prewoven metallic braid shall be cleaned in asuitable solvent to remove contamination prior to installation over the harness (see Chapter 15)(Requirement).9.8 Insulation Sleeving/TubingInsulation sleeving shall be installed on all terminations that are not otherwise insulated orpotted, except those at ground potential (e.g., overall shield and coaxial cable terminations)(Requirement). Sleeving shall be installed to meet the dimensional requirements of theapplicable drawing or specification (Requirement).9.8.1 Heat-Shrinkable Sleeving. The heat-shrinkable sleeving selected shall be larger than themaximum diameter of the object being covered, and after shrinking it shall provide a tight fitover the object in the area of maximum diameter (Requirement). This will cause the sleeving tohave a tight mechanical grip on the item it covers. A guide for selecting sleeving sizes is givenin Table 9-3. There shall be no partially or incompletely shrunken areas (Requirement).Sleeving may have a slight surface crazing, but it shall be free of cracks, punctures, and charredor burned areas (Requirement).9.8.2 Tubing. Tubing shall be secured by spot ties or otherwise restrained to prevent them fromsliding back and forth over the wire bundle (Requirement).Page 47 of 114