dielectric and the oil must be replaced. A promising mechanism for 

 making the electrical contacts underwater has, however, been developed 

 for a low-voltage connector application by the Crouse-Hinds Company 

 under contract to the Mare Island Naval Shipyard. 



The use of pressure-compensated, oil-filled volumes provides the 

 ability to assemble or disassemble the connectors for repair in the 

 field not provided by potted connectors. Installing a heat-shrink boot 

 over the cable end is also fairly time-consuming and complicated, but it 

 is effective, and is easy to install and repair on a wide variety of 

 cables. It also offers considerable compliance, so that relative motion 

 between the cable armor and the internal conductors under pressure and 

 other cable loads can be tolerated without breaking the seal. 



In addition to still being in the experimental or early prototype 

 stage, these large-scale connectors have other basic limitations. They 

 are large in size so that they cannot be handled over drums or sheaves. 

 They are heavy, even in water, so that they require special handling sys- 

 tems to allow underwater connection by divers or submersible. 



Reliability 



Reliability of an item of equipment is the probability that the 

 equipment will operate satisfactorily for a given interval of time (or 

 number of cycles) when used under specified operating conditions and 

 maintenance programs. 



Maintainability is the probability that a failed item of equipment 

 will be restored to operating conditions in not more than a specified 

 interval of down time when maintenance and administrative conditions are 

 stated. 



Quality control is the set of disciplines and techniques which en- 

 sures that the manufactured item conforms to the design specifications. 



The most urgent problem associated with the failure of components 

 subjected to deep submergence pressures has been the control of quality 

 (see Reference 1). This control of quality has been absent during one 

 or all of the various stages of manufacture, assembly, test, handling, 

 shipping, and installation. Certainly poor component design has been 

 responsible for many system failures in past years; however, many fail- 

 ures have been rightfully attributed to inadequate manufacturing and 

 installation quality control. The following paragraphs in this section 

 are addressed to quality control and reliability considerations in 

 connector and penetrator design. 



The following is a listing of problem areas that have been identified 

 in past years as failure modes for cable connectors, harnesses, and 

 penetrators : 



1. Inadequate bond of the molded connector boot to the cable. 



2. Inadequate bond of the molded connector boot to the 

 connector shell. 



3. Voids in the mold boot of the connector. 



4. Damaged cable jackets in the mold cable clamp area, 

 especially in neoprene-molded boots where the cable is 

 held in the mold. 



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