In recent years, the application of carbon fiber composite materials in the marine field has become more and more extensive. Corrosion in the marine environment, high pressure, and strong shear effects caused by underwater undercurrent flow have imposed strict requirements on the material's corrosion resistance, strength and fatigue performance. . Carbon fiber composites have excellent skin resistance and corrosion resistance, and they have an advantage in the development and expansion of the marine field. Nowadays, carbon fiber composites are playing an increasingly important role in the marine field.
First, the application of carbon fiber composite materials in the construction of subsea oil and gas fields
Carbon fiber composite materials can be used as production well pipes, sucker rods, storage tanks, subsea pipelines, decks and other components in oilfield drilling platforms. Its manufacturing process is divided into pultrusion process and wet winding process. Pultrusion is generally used on ordinary pipes and connecting pipes. The winding method is generally used as the surface of storage tanks and pressure vessels, and can also be used in anisotropic flexible pipes. Carbon fiber composite materials can be wound and arranged in the armor layer at a specific angle.
For a 1500m water depth drilling platform, the mass of the steel mooring line is about 6500t, and the density of the carbon fiber composite material is 1/4 of that of ordinary steel. If the carbon fiber composite material is used to replace part of the steel, the load on the drilling platform will be significantly reduced. To a certain extent, the construction cost of the platform can be saved. The sucker rod must be reciprocated during operation. Due to the imbalance between the pressure of the seawater outside the pipe and the pressure inside the pipe, fatigue fracture of the material is easily caused, and this problem can be solved with carbon fiber composite materials. Due to the corrosion resistance of the seawater environment, carbon fiber composite materials It has a longer service life in seawater than steel and can be used at deeper depths.
The carbon fiber composite continuous sucker rod is a film-like ribbon structure with good flexibility. Produced and used in the United States in the 1990s. It is produced by using carbon fiber as the reinforcing fiber and unsaturated resin as the matrix material, which is crosslinked and cured at a high temperature through a pultrusion process. From 2001 to 2003, China used carbon fiber sucker rods and ordinary steel sucker rods in a pilot project in the Chunliang Oilfield. The use of carbon fiber sucker rods can significantly increase oil output, reduce the load on the motor, and save energy by comparison. In addition, carbon fiber composite sucker rods are more resistant to fatigue and corrosion resistance than steel sucker rods, and are more suitable for application in the development of subsea oil fields.
Application of carbon fiber composite materials in offshore wind power
China's coastline is about 1,800 km, and more than 6,000 islands. The wind power in the southeast coast and island areas is rich and easy to develop. The offshore wind power resources are abundant. It is an important area for future development. It is also the most advanced and most demanding wind power area. Has been vigorously promoting the development of offshore wind power. More than 90% of the weight of wind power generation blades is composed of composite materials. Large offshore wind power and large power generation are bound to require larger blades and better specific strength and durability. Carbon fiber composites have high specific strength and specific stiffness, which can meet the requirements for the development of large-scale, lightweight, high-performance, low-cost power generation blades. Compared with glass fiber composites, carbon fiber composites are more suitable for marine applications. .
Carbon fiber composites have significant advantages in marine wind power. Carbon fiber composite blades have low quality, high rigidity, and the modulus is 3-8 times that of glass fiber products. Under the marine environment, the humidity is high, the climate is changeable, and the fan works 24 hours. The blades have better fatigue resistance and can better withstand the bad weather; the aerodynamic performance of the blades is improved, and the load on the tower and the axle is reduced, so that the output power of the fan is smoother and more balanced, and the energy efficiency is improved; the use of carbon fiber Through the special structural design, it can effectively avoid the damage caused by lightning to the blades; reduce the manufacturing and transportation costs of wind turbine blades; and have vibration damping characteristics.
Application of carbon fiber composite materials in marine engineering
Carbon fiber composites are used in marine engineering buildings because of their lightweight, high-strength and corrosion-resistant properties. They replace traditional reinforced building materials with tendons and structural parts to solve the problems of seawater erosion of steel bars and high transportation costs over long distances. It has been used in offshore islands and reefs, docks, floating platforms, and light towers. The use of carbon fiber composite materials for engineering repair began in the 1980s. Japan's Mitsubishi Chemical Corporation took the lead in studying the mechanical properties of carbon fiber composite materials and their application in engineering reinforcement. The initial research focus was on the use of carbon fiber composites to strengthen reinforced concrete beams, and later developed to strengthen and strengthen various civil engineering.
The excellent properties of carbon fiber composite materials make it have broad application prospects in marine applications. In general, compared with mature applications in aerospace and other fields, the application of carbon fibers in the marine field has started relatively late. At the same time, the cost of carbon fibers High is also an important factor restricting its large-scale application. With the development of the maritime military and the development of marine resources, vigorously promoting the application of carbon fiber in the marine field is an inevitable trend of development. On the other hand, the increasing demand for carbon fiber composite materials in the marine field will also promote the carbon fiber industry from application traction. The healthy development of the chain.