Feature ArticlePortable Winch Technology For Use on Smaller Vessels
By Gary Nishimura
Consultant to Markey Machinery
Auke Bay Laboratories
National Marine Fisheries Service
Traditional winches designed for oceanographic research have evolved with several unique features that set them apart from their relatives in commercial applications. Characteristics such as a large drum capacity for long lines, precision level-wind mechanisms and advanced motion compensation systems that maintain line tension in heavy seas have satisfied research mission requirements for greater depths, higher speeds, and improved control and repeatability. But throughout this evolution, the typical winch remains a relatively heavy deck-mounted machine that is powered by the vessel's hydraulic or electric system. This design works well for permanently installed equipment, but it can create operational challenges for temporary installations, and it cannot be used on small vessels.
A Sidewinder winch onboard the 24-foot RV Quest, which performs oceanographic work in nearshore operations.
Temporary equipment installations are increasingly required as the existing fleet of dedicated research vessels continues to age and more scientists turn to charter vessels and vessels of opportunity to complete their missions. Using a variety of vessels requires the frequent transfer of equipment between unfamiliar platforms with different deck layouts, space constraints and existing machinery. In addition to temporary installation requirements, new advances in oceanographic instrumentation and equipment have led to more compact, lightweight packages that permit deployment from vessels as small as 24 feet in length, greatly exacerbating the problems of winch installation, limited deck space and weight allowance. Some equipment has become small enough to deploy by hand, but most is still too heavy or requires operational protocols that dictate a powered winch. These factors have created increasing demand for winches with traditional oceanographic quality and features but packaged in a small and portable configuration.
Winch portability can be defined in many ways and is related to the handling equipment available. For small vessels without a crane, portable equipment must be handled directly by personnel; the maximum weight that can be handled by two people is about 150 pounds. In addition, small vessels often have limited onboard power sources and therefore require a dedicated power supply that is also portable. Gas-powered generators are an economical option but also pose safety hazards due to their high temperature, high voltage and noisy characteristics. Finally, winch installation and removal must be fast and simple, without permanent modifications to the deck or other parts of the vessel.
Defining Portable Winch Parameters
After receiving operater feedback, Markey Machinery (Seattle, Washington) developed a small portable winch named Sidewinder. Identifying winch requirements and developing a machine to satisfy them depended on observations and feedback gained through cooperation with staff at the Auke Bay Laboratories (ABL). The ABL samples juvenile salmon, their fish predators, zooplankton prey fields and physical oceanographic features from May to August during the annual Southeast Alaska Coastal Monitoring (SECM) research survey. Sampling is conducted within a few miles of shore where typical bottom depths are 100 to 500 feet.
During this work, a variety of small oceanographic instruments and nets are deployed from NOAA ships and chartered vessels ranging from 24 to 165 feet in length. Vessel configuration varies widely, and sampling operations must be adapted to each vessel platform. Fish trawling is accomplished with a research-scale surface trawl net that requires large winches and reels typically located amidships. Oceanographic sampling requires smaller winches that are typically mounted on one side, on an upper deck or on both. Some vessels do not have a winch of the appropriate size or location to conveniently deploy small instruments according to standard specifications. In these instances, the SECM project has provided a hydraulic winch with a separate electronic display showing meters of line out. However, this winch is relatively heavy and nonportable and requires a semipermanent mounting location near hydraulic lines. Like many winch systems, the rigging is directed through a remote block on a davit or boom that pivots to one side, where the sampling gear is attached. In addition, this winch is inconvenient because several staff members are needed to monitor its operation and coordinate with vessel power to meet specific sampling gear requirements, such as net deployment and retrieval at defined speeds and line angles. The operator uses winch-mounted controls, a second person reads line speed from an electronic display located away from the winch, and a third person monitors the line angle (40° to 50°) manually using an inclinometer. To continue this article please click here.
Gary Nishimura is a professional engineer and consultant to Markey Machinery. He has several years of experience designing specialized machinery for the commercial marine and oceanographic industries.
Molly Sturdevant is a fishery research biologist at Auke Bay Laboratories with more than three decades of experience in marine ecological research. The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the National Marine Fisheries Service.