Two 100-ft-long carriers handle cables that supply power to gates and vehicle arrestors on the John T. Alsop, Jr. Bridge, Jacksonville, Fla. Anodized aluminum crossbars are bolted in place at more than 400 links. Stainless steel bars include additional vertical separators and horizontal dividers to keep cables in place.

Cable and hose carriers prevent the lifelines of automated machinery from tangling and fatiguing prematurely by limiting flexion to a specified radius, and imparting a gentle rolling to feed lines in and out as machinery moves. But there's a lot more to applying cable and hose carriers than just stringing cables through — and picking a carrier out of a catalog is not likely to provide the best possible solution. After all, application variables make it difficult to satisfy weight requirements, travel speeds, environmental conditions, mounting configurations, and space limitations with one standard product. A better tactic than catalog shopping or even developing a custom design from scratch, which can be prohibitively expensive and time-consuming (particularly for limited quantities) is an approach somewhere in the middle.

Assembling standard components (including links, crossbars, and accessories) into configurations that satisfy a specific application often makes for ready-to-install carrier subassemblies, with all the necessary accessories, mounting hardware, brackets, and fabrications. This is a practical way to achieve the results of a custom cable and hose carrier at a reasonable cost.

Choosing which type

Underground directional drills use high-strength metal carriers to handle multiple lines in demanding operating conditions.

Most cable and hose carriers consist of parallel side links joined together by crossbars that support the hoses, where pivot pins and stops allow the links to travel through a predetermined arc. Some designs are open between links, while others are completely enclosed for greater cable and hose protection.

Open, nonmetallic carriers are made of heavy-duty fiber-reinforced nylon, and are most suitable for high speeds and long travels. These carriers are nonconductive and corrosion-resistant, particularly when they incorporate nonmetallic pins or bars. Typical uses include machine tools and industrial robots. Lighter versions are also suited to automation machinery or where quiet operation is necessary.

Completely enclosed carriers are another link-type design that envelops the top and bottom of hoses and cables in environments with abrasive materials. Several enclosure subtypes allow easy access to cables and hoses with removable slide strips or plates.

Metallic link-type carriers consist of metal links joined by hardened steel pins that act as both bearings and lock points. They are suitable for machine tools, cranes, industrial robots, mobile and construction equipment, and steel mill machinery.

Demanding applications

he end of a metal cable and hose carrier on an underground drill includes hose sleeves inside to help control hoses and contain any oil. Velcro closures along the hose sleeve’s length make these easier to install during production, and simplify field repair or replacement.

In some applications, carrier design is central to long-term machine operability. One example is aerial boom lifts — built with ever-longer lengths for greater reach. Cable and hose carriers located between telescoping boom sections allow machines to reach greater heights with a smaller retracted boom envelope. By controlling the motion of hydraulic hoses and wiring cables attached between the base and tip of the boom sections, carriers also prevent cable fatigue.

Minimized weight and resistance to environmental conditions are key. Light nylon-based materials are one option. New metal carriers with less steel content are another way to reduce weight, as well as exposure to steel market instability. These light yet strong units can support the longer cantilevered spans increasingly common in aerial lift design.

Underground directional drills are another illustrative application. Here, carriers free operators from having to pace with the machine's carriage, and allow them to remain stationary. But the challenge is managing hydraulic lines to the carriage that feeds drill pipes used in the operation, and electrical cables for controls, speed sensors, and solenoid-operated valves. Dirt, oil, and weather extremes abound; a water and bentonite mud mixture flows during operation, and there is exposure to hydraulic oil during maintenance.

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