Marine U-Joints with Improved Water Resistance

Underwater universal joints and complete drive shaft assemblies

Harsh environments, like marine and underwater applications, call for corrosion-resistant materials. Machines and components demand an exceptionally high resistance to corrosive elements and Belden products are designed to meet these strict requirements. From underwater oil field equipment to drinking water pumping systems and food processing applications, Belden’s Universal Joints and complete drive shaft assemblies are available in a variety of stainless steel grades. Various hub configurations, lubricants and additional protective measures, such as boots, are available for use in a wide range of corrosive environments. Belden’s Actuator Connection Shafts, developed for an undersea oil valve actuator, illustrates a deep knowledge of marine applications. This specific installation was located on the sea floor, some 330 feet below sea level where valves were opened and closed by small submarines.

To allow the submarines to perform this operation from a safe distance, the valves were fitted with articulated shafts to transfer the actuation movement and force to other parts of the system. The shafts were constructed like telescopes to allow change in length to adapt to small movements and relocation of the equipment’s position. The complete assemblies were also designed for easy disassemble, transportation and reassemble for refitting. Due to the extremely harsh underwater environment, Belden used a higher-grade stainless steel for the universal joints. The yokes of the universal joints were made of extremely corrosion-resistant 316L stainless steel. To prevent galling and to improve the joints’ friction properties, the yokes’ contact surfaces were PTFE-coated. The pins and blocks were also manufactured from 316L stainless steel and protected with grease-packed boots.

To provide higher strength and improved wear resistance, Belden’s standard stainless steel joints have AISI 303 stainless steel yokes and AISI 416 steel pins and blocks. Standard single joints can be modified with a variety of stainless steel grades, including 304, 316, 17-4 and 15-5, to meet specific applications’ requirements. Diameters range from 1/2 " (13 mm) to 6" (153 mm) with a standard operating angle of 35°. 

Additional Application Briefs Information