Davit arms come in many sizes and styles to facilitate the particular functions necessary for their designated roles. Because of this, customization is a key consideration when it comes to their design and production.
What Are Davit Arms?
Davit arms are apparatuses made of wood or steel and are sometimes jointed. They come either singularly or in pairs, depending on their need, and fit at the top of any drop-off where they serve primarily as cranes for a variety of purposes.
Historically, these devices served large vessels as a means of lowering dinghies and other small craft. In 1926, A.P. Schat set forth to improve davits systems by making them more dynamic and safer in operation. Davit makers have used his patented designs as a guide ever since.
The arms, specifically, come in at least three basic styles, although other combinational forms exist as well.
Lean-over – for extension over edges.
Vertical – with a spine for high-rise positioning.
Portable Cantilever – for maneuverability or transportation.
Features for davit arms are contingent on the particular purpose, but typically involve configuration capabilities, swinging and flexing adjustments, weight balance and space accommodation. Davit arms are just as much for enhancing appearance and facilitating human movement as they are for performing their primary tasks. For this reason, many industries have adopted their use.
What Do Certain Industries Use Them For?
Several industries implement davit arms, and for multiple uses. That shows just how versatile and sophisticated these devices have become.
Public Safety electric utility requires davit arms for conductor/fiber optic suspension. Utility vehicles feature davit units to conduct rescue or perform work in confined areas.
Construction davit arms serve primarily as a means of retrieval and elevation. They quite often perform these tasks simultaneously, as in the case where pallets or iron beams ascend, descend or shift from one area to another when delivering personnel and/or supplies where they need to go. This includes confined spaces where access is difficult.
Manufacturing davit arms work much like jib cranes that facilitate the production process. Assembly lines require davit arms to crane parts into position or lift away obstructions to make work easier.
Cruise Lines’ davit arms lift/drop cargo, anchors and lifeboats. These operate on hydraulic, free-fall and/or mechanical systems controlled by a limit switch.
Military/Naval davits hoist/lower lifeboats with the double-link Pivoted Gravity system. They use a drum-type winch that has a wire rope fall. Retrieval capabilities increase anchorage height and decrease mast extension when necessary.
Fishing davits, also called “firm davits,” function as cranes to lift the anchor flukes to the bow. Curved arms, made of timber or iron, extend over the stern sides to lift/lower lifeboats. These davits also raise fishing nets and other hauling necessities.
Oil/petrochemical oilrigs use davit arms suspend and move items such as oil drums for reorganization, cleaning and damage control purposes. These facilities also have lifeboats for emergency departure in case of fires.
Shipping davit arms elevate/suspend personnel, cargo and supplies, as well as offer support and balance for the purpose of organization, clean-up and damage control.
In the current age, davit arms are a necessity in virtually every aspect of life. The continuing expansion of their designs reflects the growing needs of human civilization, and shows how davit systems will influence the technology to come.