ACTU-VATOR: Folding Hatch Cover Innovation From The Main Deck, Inc.
The Main Deck, Inc. has designed a new type of folding hatch cover that may be fitted at both weather deck and tweendeck hatchways. In its simplest form, this type of hatch cover consists of two, flat-topped panels, similar in basic construction to those currently in use and driven by hydraulics, but completely self-contained inside the hatch cover. Adjacent panels are hinged together so that they fold. The panel at the stowage end is hinged to a plinth, welded to the deck. Mechanical actuators, gearbox, drive shaft, pillow block bearings and electric motor are contained within the cover. The mechanical actuator unit designed for the system is reportedly very safe to operate, inexpensive and durable for a shipboard environment.
Components Reportedly, parts and equipment of the ACTUVATOR system are relatively inexpensive, and due to the system's simplicity, repairs can be performed by ships personnel in port or underway. The ACTU-VATOR lifting system is a simple arrangement consisting of the following components: • Electric Motor. Five-hp, coupled to accept a 2.25-inch stainless steel drive shaft. The motor is controlled by a hand-held control unit, attached to a flexible cable, plugged into the coaming or convenient receptacle, outside the cargo hold. The control unit is attached to an electric cable, lengthened to suit.
• Motor Drive Shaft. 2.25 in., stainless steel, supported midway by a pillow block bearing, running on to the gearbox.
• Gear Box. Transfers power from the single, incoming drive shaft to a transverse drive shaft used to power the mechanical actuators. • Mechanical Actuator. Transfers power from the transverse drive shaft, creating a lifting movement as the screw moves forward and a closing movement as the screw retracts.
• Yoke. Installed at the end of the actuator screw. The opposite end of the yoke is pinned through the cam action hinge assembly, which is attached to the hatch cover at the break point. Different configurations of various designs can be incorporated into cargo access openings. For a larger application, the size of the actuator and drive shaft would be enlarged, and the number of actuators and the rated hp of the electric motor would be increased. Different types of gear reducers can be introduced to maximize power configurations. All the drive system's components are attached to the underside of the hatch cover panel. All drive mechanisms are held in place by brackets welded to the underside of the top panel and supported by cross beams. This places the drive system out of harm's way and out of the elements.
The ACTU-VATOR drive mechanism is a positive locking system, so unless the motor is engaged and the drive system energized, the covers will not move. This design feature reportedly prevents covers from free falling. For emergency operations such as a power failure, a manually operated ratchet assembly is incorporated into the drive train. The Main Deck claims ACTUVATOR hatch covers can be operated virtually by anyone who is capable of operating the hand controls (open/close), and there is no need for more than one operator. The covers can reportedly be stopped in an instant in the event of an emergency. Applications for the ACTU-VATOR system include, but are not limited to, ship's cargo hatch covers on coamings and ship's cargo hatch flush hatch covers in the weather and below decks; barge cargo hatch covers; shipboard aircraft hangar covers; large stores hatches; single section stern, bow ramps and side port ramps; ship's interior ramps; bow, stern and side port door openings; submerged door openings for torpedo tubes and missile launch tubes; large shipboard doors in bulkheads and deckhouses; inland waterway lock gates; and shore side facility doors horizontal, inclined or vertical.
For more information on The Main Deck Circle 32 on Reader Service Card