Published: 2026-08-23
Underwater robots (ROVs), underwater cameras, and deep-sea exploration equipment all use neutrally buoyant cables. Many customers think that neutral buoyancy means 'able to float in water,' but the core of a neutrally buoyant cable is **density matching**—making the net weight of the entire cable in water close to zero.
Ordinary floating cables rely on a foam layer to provide buoyancy, making the entire cable "float upward." When equipment tows it, additional resistance is generated, affecting the attitude control of underwater robots; in contrast, zero-buoyancy cables achieve a "zero-gravity" state in water by precisely balancing buoyant materials with weighting materials, allowing the cable to move freely with the equipment without floating or sinking.
There are two key technical points to achieving neutral buoyancy: first, the uniform foaming of buoyant materials, with density controlled between 0.5-0.8 g/cm³, and they must withstand high deep-sea pressure without collapsing; second, the weight calculation of the conductor and sheath, with each core calculated individually for multi-core and different cross-sections, so that the overall cable density is uniform. In addition, the water pressure differences at depths of 100 meters, 300 meters, and 1000 meters are significant, and the foamed layer will be compressed in deep water, causing changes in buoyancy, so it must be designed according to the actual water depth.
Selection Recommendation: Inform the manufacturer of the underwater robot's working depth, cable length, number of cores, and signal requirements. Shanghai Suoqi Zero-Buoyancy Cables support customization of 3-pair twisted 6-core, multi-core composite (power, signal, fiber optic) cables, with buoyancy proportion calculated according to the water depth.
About Shanghai Suoqi
Shanghai Suoqi Electric Wire & Cable Co., Ltd. is a specialized cable enterprise focusing on the research and development, design, production, and sales of special flexible cables. The company's products cover a series including reel cables, flat cables, drag chain cables, encoder cables, polyurethane cables, seawater-resistant cables, seawater-resistant network cables, and high-altitude vehicle cables, which are widely used in ports machinery, mining, industrial automation, marine engineering, and other fields. For more product information or inquiries, please call 13311756197 (same number on WeChat).