Water Pressure Resistance Research Articles

Performance Analysis Based on Bonded Surface Designs for Stitchless Welded Products

This study selected three model designs used for air injection type welding clothes designed for insulation purposes and analyzed the performance of each design. The bending characteristics were analyzed in order to identify the flexibility of the welded areas; subsequently, the seam breaking strength and water pressure resistance were analyzed to identify the bonding strength. In addition, two types of waterproof fabric, polyurethane (PU) coated 2 layer and PU laminated 2 layer fabrics, were used for a performance analysis, according to fabric processing specifications. The circle type showed the highest flexibility in the terms of bending characteristics that influence wearability and were followed by the wave and the straight type. In terms of breaking strength, the straight type showed the highest breaking strength, followed by the wave and the circle type. The water pressure resistance analysis found that the wave type was superior to the straight type in terms of water pressure resistance. The wave type is deemed to be a design type suitable for maximizing performance, provided that the issue of stabilization in the welding production process is addressed. Looking at the bending characteristics of waterproof fabric for each specification, the laminating waterproof cloth outperformed the coated waterproof cloth in terms of flexibility. However, in terms of seam breaking strength, the coated waterproof cloth outperformed the laminated cloth. In contrast, the water pressure resistance of the laminated waterproof fabric was found to be higher than the coated waterproof fabric, leading to the conclusion that the bonding strength of the laminated waterproof fabric is higher than that of the coated waterproof fabric based on the assumption of injecting air.

Effect of spacing distance on loading capacity and pressure resistance of miniature boat fabricated from superhydrophobic phenylenebenzobisoxazole (PBO) fiber bundles

An artificial superhydrophobic Poly-p-phenylenebenzobisoxazole (PBO) fiber bundles were designed and prepared using chemical surface modification. Water contact angles as high as 166.3° were achieved. The loading capacities and pressure resistances of these PBO fiber bundle boats were characterized. The highest loading weight of our superhydrophobic boats was more than 9.42 g, which was attributed to the air film trapped around the PBO boat surfaces. The depth of the water pressure resistance was about 656.4 mm.

形状記億合金で駆動する海外極限作業ロボット 深海底資源開発に向けての一提案

An advanced submarine robot model actuated by the driving force in thermo-mechanical transformation of shape memory alloy (SMA) was developed jointly by the engineering faculty of Tohoku University and Honda Seiki Co., Ltd.. A model “robot crab” about 1/20 of practical size was constructed with the artificial muscles of Ni-Ti SMA springs or wires in the every joint parts of the moving legs and it moves by electrical pulse currents with microcomputer controls. It is simple in structure and is also characterized by high strength, high water-pressure and corrosion resistance. It has more rapid motion under water than in air due to the high cooling capacity of water. Based on these characteristics and the advantages of SMA actuator, we have proposed and developed an extreme operation SMA robot model to investigate and collect very deep submarine resources. We also talk about the possibility, some technical problems and necessity for international cooperation in harvesting the deep submarine resources by this type SMA robot in near future.