A giant octopus constructed of rebar and mesh has been sunk to the bottom of the sea off the coast of Virgin Gorda in the British Virgin Islands as part of Project YOKO, the world’s largest underwater art installation and marine life habitat. It will be open to divers for a small fee, raising funds for research into the area’s coral reefs.
Mandy Barker has a new photography series out called “Beyond Drifting.” It continues her work documenting trash in the ocean and her study of how this pollution affects the environment.
Caption: Phoronilasteri crae (Tricycle wheel). Specimen collected from Whitepoint, Cobh shoreline, Cove of Cork, Ireland. (Photo Credit: Mandy Barker)
Ocean Signal has appointed Rich Galasso as its new U.S. sales manager.
Bringing more than 20 years’ experience in the marine industry to the role, Galasso joins Ocean Signal following a seven-year stint as regional distribution manager with satellite communications and tracking company Globalstar/SPOT.
“Chasing Coral” will debut on Netflix and in theaters in New York and L.A. July 14. This doc by Jeff Orlowski, which was included in the 2017 Sundance Film Festival, captures the effort to invent a time-lapse camera to show the process of coral bleaching. Learn more about the film here.
Low-Density Polyurethane Foam for Subsea Buoyancy Systems
Addressing Buoyancy Requirements with Hydrostatic, Pressure-Resistant Foam
By Dr. G. Joel Meyer
According to a forecast by the research firm MarketsandMarkets the market for UUVs, specifically ROVs and AUVs, is expected to reach $4 billion by 2020. The increase in the ROV commercial segment is due to the growing demand for survey and seabed mapping, offshore drilling and pipeline inspection, while the increase in the AUV market can be attributed to greater activity on the military and scientific research front.
The design and material considerations for UUVs are heavily dependent on the nature of its applications, with the right buoyancy material counting as one of the critical choices manufacturers have to make. Successful operation of these vehicles requires buoyancy that performs at a specific range of depths, while taking into consideration chemical environment conditions.
The LAST-A-FOAM R-3300 buoyancy foam series provides a range of hydrostatic, pressure-resistant polyurethane foam in various densities that address common buoyancy requirements.
LAST-A-FOAM R-3300 foam is specifically formulated to be a dimensionally stable, closed-cell, water- and impact-resistant foam that can withstand the harsh conditions of shallow to mid-depth subsea operation. The high strength and modulus of the polyurethane foam is a result of the proprietary formulation of highly crosslinked polyurethane foam, along with a manufacturing process that minimizes cell structure variation throughout the material. Polyurethane foam does not support the growth of micro-organisms and will not rot or decay over time. These properties make it optimal for subsea buoyancy systems, marine and underwater robotics applications, and as a core material for resin transfer.
General Plastics has an in-house testing method based on ASTM-D 570 that was developed to simulate subsea conditions. In this hydrostatic testing, a sample of foam is placed in a reinforced pressure vessel and filled with water to a pressure corresponding to specific oceanic depths, with the assumption that pressure increases by 1 psi per 2.31 vertical feet. For example, material that is qualified to 1,200 ft. is placed in a pressure vessel at 580 psi. Using this method, we can simulate the conditions that the foam will be exposed to at a large number of varying depths. The material is then held at pressure for 24 hours.
After the test is complete, the sample of foam is then measured for dimensional stability and water absorption. As seen below in Table 1, the average volume change for all densities of material is well below 1 percent. With an average weight gain range of only 2.0 to 2.8 percent, the material shows minimal changes when subsea pressures are applied. The data below is based on an average of more than 300 different batches of material produced to full scale.
|Density||Average of Vol. Change (%)||Average of Weight Gain (%)|
LAST-A-FOAM R-3300 has shown to retain strength and stability when put through these harsh underwater conditions. General Plastics Mfg. Co. certifies the naked foam to be stable to up to 1,200 ft. for 25 pcf material, and it gains even more stability when an epoxy or polyurea coating is applied. In all of the foams tested, depths accessible using coated R-3300 foam doubled when compared to the noncoated foam (see Table 2).
Table 2: Depth Chart
|Products||Density (lb/ft3)||Tested Depth (ft.) (uncoated)||Tested Depth (ft.) (coated)|
Physical and Thermal Property Data: Case Study
Outland Technology, manufacturer of underwater systems, has been using General Plastics’ LAST-A-FOAM R-3300 polyurethane foam series for ROVs in applications such as oil rig and pipeline inspections, collegiate research and military uses. In earlier projects, the company’s ROV flotation material requirements included low-density conditions, buoyancy up to 500 ft., and the ability to customize foam size and thickness to fit individual applications. Their product choice, the R-3315, fit the density requirement at 15 lb. per cubic foot and could go to depths up to 700 ft. uncoated and 1,400 ft. when coated. Additionally, Outland Technology had the ability to machine the foam to desired thickness.
Over the years, Outland Technology designed their ROV with higher voltages and better cables giving it the ability to reach depths of 1,000 ft. or 500 psi. The expanded range of the R-3300 foam series allowed General Plastics to address the customer’s evolving needs. With density ranging from 12 to 25 lb. per cubic foot, the R-3300 foam series provides buoyancy with depths up to 1,200 ft. uncoated or 2,400 ft. coated. It is dimensionally stable, performs in freshwater and saltwater and is easy to machine, coat and paint.
Dr. G. Joel Meyer is the chemistry laboratory manager at General Plastics Manufacturing Co., where he oversees a team of chemists and materials scientists to bring new advanced materials and applications to market. As head of the company’s R&D group, he works with customers to create products that fulfill specific requirements and applications.
The first-ever World Ocean Festival will take place for a week starting June 4 in New York City. It will be the prelude to The Ocean Conference June 5 to 9.
The festival, organized by the Global Brian Foundation, will bring public attention to the UN Sustainable Development Goals (SDGs), specifically Goal 14 on conservation and use of the oceans, seas and marine resources for sustainable development.
The conference will address ocean-related problems cause by human activities.
Learn more here.
Photo Credit: UN/Martine Perret
Do you use Chesapeake Technology‘s SonarWiz side scan sonar mapping and processing software? If you do, you could enter the contest to send images that will be considered for the cover of Sea Technology magazine’s June issue.
Submissions are due May 19.
You can also enter to win a $20 gift card.
Caption: Last year’s contest winner.
Ninety percent of fisheries around the world are threatened or depleted, according to the United Nations Food and Agriculture Organization. This affects lives and livelihoods worldwide, particularly in the developing world.
China’s aggressive expansion of fishing practices, including illegal ones, is exacerbating the problem, The New York Times reported. Read the full article here.
Caption: A school of jack mackerel. (Photo Credit: Richard Ling)
Ranking behind Singapore are Hamburg, Oslo and Shanghai, in respective order.
Experts say Singapore would remain the “most important city” come 2022, although Shanghai will likely become the second most important maritime hub.