Materials in Motion

Retrofit Drives: Benefits and Disadvantages

Retrofit Conversion Kits for Jib Cranes

What’s the point of a Retrofit Conversion Kit?

Retrofit conversion kits—better known as retrofit jib drives—are used to convert an existing manual rotation jib crane to a motorized system. Motorizing your jib crane provides powered rotation of the boom, which is ideal for lifting heavy loads. Powered rotation of the jib boom is also imperative for certain applications, particularly for workers using the crane on a busy or dangerous factory. In these situations, manual rotation of the jib boom can be unsafe, impractical, and inefficient. If your manufacturing operation is constantly growing or you are concerned about the safety of employees who need to manually rotate the jib boom, a retrofit jib drive is the way to go.

Obviously, most overhead crane manufacturers produce and sell motorized jib cranes as standard systems in their product lines. Motorized jibs are available for freestanding systems, wall-mounted and wall-cantilever systems, and even mast-style systems, whereas retrofit jib drives are only available for freestanding systems. But, for companies that have already purchased a manual freestanding jib crane, a retrofit jib drive is far less expensive than purchasing an entirely new motorized system. The jib drive, quite simply, converts your existing crane to a motorized system. So what’s the catch?

There really isn’t one. Universal retrofit jib drives fit any freestanding jib crane with a box-style head. They are engineered using a modular design that bolts onto the back of the box-style head assembly for quick conversion from a manual system to a motorized one. Most jib drives also feature a high-efficiency electric motor and worm gear reducer.

What Is A Worm Gear Reducer?

Worm gear reducers have many names, depending on the industry and application for which they are being used. They are generally comprised of terms like “gearbox” and “speed reducer”, which are use interchangeably for power transmission and motion control applications. Gearboxes, for instance, are used for speed reduction and to increase torque.

The term “speed reducer” became synonymous when gearboxes were first introduced to multiple industries. That’s because speed reduction is an important function for the gearbox, allowing manufacturers to replace cumbersome belts and outdated pulley technology.

You may have noticed that the term gear reducer is used interchangeably with gearbox and speed reducer. Other common terms used to describe worm gear speed reducer technology are terms like “gear motor” or “geared motor”. Gear motors are the same as speed reducers or gear reducers, only they provide a motor directly mounted to the input. Most overhead crane manufacturers prefer to use worm gear speed reducers for their flexibility, compactness, durability, and longevity.

Why Is A Worm Gear Speed Reducer Important?

A worm gear speed reducer is an important part of the motorization process because it provides a wide-variety of industrial applications with effective gearing performance. The SE Encore series of worm gear speed reducers, for instance, provides a wide variety of industrial applications with highly proficient gearing performance. The SE Encore series is also developed with performance features that boast up to 40 percent higher output torque ratings. Additionally, this particular series affords engineers a vast array of shafting and mounting options, motor connection options, and gear configurations, which is why Spanco manufactures its retrofit jib drives using this particular series of speed reducers.

Furthermore, the SE Encore Series operates with an optional on/off vent and features a patented epoxy coating system that can withstand everyday use and harsh environmental and duty conditions, such as outdoor use or installation for cranes in corrosive environments. This particular line of worm gear reducers also uses a premium H1 food-grade synthetic lubricant that eliminates the need for oil changes during normal operation.

As we stated above, the worm gear reducer is an essential function in the design of a retrofit jib drive. That’s because the worm gear reducer drives a set of large, heavy walled steel rollers, which are fitted with polyurethane treads for exceptional durability and traction on the crane’s mast. The rollers maintain accurate and consistent pressure against the mast, using a spring-loaded tension adjustment mechanism to assure smooth operation. The drive roller is easily adjusted to ensure a constant driving force.

Most jib drive control panels include a mainline contactor, reversing magnetic contactors, thermal overload, 110V fused control transformer, branch circuit fusing to the crane motor, and solid state “soft start” control adjustable for time and torque—all sealed off in a NEMA 3R enclosure. Although the worm gear reducer is engineered for both indoor and outdoor applications, retrofit jib drives are only recommended for indoor applications, although some can be customized to meet your outdoor needs.

Overall, adding a retrofit jib drive to convert your existing manual jib crane to a motorized system is an easy, cost-effective way to solve potential worker’s compensation issues or safety concerns. Upgrading your current system is far less expensive than purchasing another new jib crane that’s already motorized, and the end-result is exactly the same.