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 the strong shear effect of underwater underflow flow have placed strict requirements on the corrosion resistance, strength and fatigue performance of the material. .
Carbon fiber advantage
Carbon fiber composite materials have excellent skin resistance and corrosion resistance, and they have an advantage in the development and expansion of the marine field. Nowadays, carbon fiber composite materials are playing an increasingly important role in the marine field.
Application 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 oil pipelines, decks and other components in oilfield drilling platforms. The manufacturing process is divided into pultrusion process and wet winding process. The pultrusion method 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. The carbon fiber composite material can be wound and arranged in the armor layer at a specific angle.
For a 1500m water depth drilling platform, the quality of the steel tether is about 6500t, and the density of carbon fiber composite material is 1/4 of that of ordinary steel. If carbon fiber composite material is used to replace part of the steel, the load of the drilling platform will be significantly reduced. To a certain extent, the construction cost of the platform can be saved. The sucker rod needs to reciprocate during operation. Due to the imbalance of the seawater pressure outside the pipe and the pressure inside the pipe, it is easy to cause fatigue fracture of the material. The carbon fiber composite material can solve this problem. Due to the corrosion resistance of the seawater environment, the carbon fiber composite material The service life in sea water is longer than that of steel, and a deeper use depth can be obtained.
The continuous sucker rod of carbon fiber composite material is a film-like strip structure with good flexibility. It was produced and applied by the United States in the 1990s. It is produced by using carbon fiber as reinforcing fiber and unsaturated resin as matrix material, cross-linking and curing at high temperature, and then pultrusion molding process.
From 2001 to 2003, China used carbon fiber sucker rods and ordinary steel sucker rods as pilots in Chunliang Oilfield. The use of carbon fiber sucker rods can significantly increase the oil output and reduce the load of the motor, which is more energy-saving in comparison. . Moreover, the carbon fiber composite sucker rod is more fatigue-resistant and corrosion-resistant than the steel sucker rod, and is more suitable for application in the development of subsea oil fields.
Application in offshore wind power
China's coastline is about 1800km, there are more than 6,000 islands, the southeast coast and islands are rich in wind resources and easy to develop, and offshore wind power resources are rich. It is an important field for future development, and it is also the most advanced and demanding field of wind power technology. Has been vigorously promoting the development of offshore wind energy.
More than 90% of the weight of wind power blades is composed of composite materials. The offshore wind is large and the power generation is large. It is bound to require larger blades and better specific strength and durability.
Carbon fiber composite materials have high specific strength and specific stiffness, which can meet the requirements of developing large-scale, light-weight, high-performance, and low-cost power generation blades. Compared with glass fiber composite materials, carbon fiber composite materials are more suitable for marine applications.
Carbon fiber composite materials have significant advantages in marine wind power generation. Carbon fiber composite blades have low quality, high stiffness, and a modulus 3-8 times that of glass fiber products; the humidity is high in the marine environment, the climate is variable, and the fan works for 24 hours.
The blade has good fatigue resistance and can better resist bad weather; improves the aerodynamic performance of the blade, reduces the load on the tower and the axle, thereby making the output power of the fan smoother and more balanced, and improving energy efficiency; using carbon fiber Through its special structure design, its conductive performance can effectively avoid the damage caused by lightning strikes to the blades; reduce the manufacturing and transportation costs of wind turbine blades; and have vibration damping characteristics.
Application on ships
Carbon fiber composite materials have good mechanical properties. The hull used to manufacture it has the characteristics of light weight and low fuel consumption, and the construction process is relatively simple, the cycle is short, and the molding is convenient, so the construction and maintenance costs are much lower than that of the steel ship.
At the same time, the interface between the carbon fiber and the resin matrix can effectively prevent crack propagation, so the material has good fatigue resistance; in addition, due to the chemical inertness of the carbon fiber surface, the hull has the characteristics that the aquatic organisms are difficult to attach to and corrosion resistance, which is also the shipbuilding One of the most important factors in material selection.
Therefore, the carbon fiber composite material has its unique comprehensive performance advantages in shipbuilding. At present, it is widely used in this field. At the same time, the development of the carbon fiber industry has been driven by the expansion of the application field.
Military ship
Carbon fiber composite materials have good acoustic, magnetic, and electrical properties: good wave permeability, sound permeability, and no magnetism, so they can be used to improve the stealth performance of warships. The use of composite materials in the superstructure of the ship not only reduces the weight of the hull, but by embedding a frequency selective layer with a filtering function in the interlayer, it can emit and receive electromagnetic waves at a predetermined frequency, thereby shielding the enemy's radar electromagnetic waves .
Carbon fiber composite materials can also be used in ship propulsion systems, used as propellers and propulsion shafting, to reduce the vibration effect and noise of the hull, mostly used in reconnaissance ships and fast cruise ships. It can be used as rudder in machinery and equipment, some special mechanical devices and piping systems. In addition, high-strength carbon fiber ropes are also widely used in naval warship cables and other military items.
Civil yacht
Large yachts are generally privately owned and expensive, requiring light weight, high strength and good durability. Carbon fiber composite materials can be used in instrument dials and antennas of yachts, rudders, and reinforcement structures such as decks, cabins, and bulkheads. The traditional composite yacht is mainly made of glass fiber reinforced plastic, but due to insufficient rigidity, the hull is often too heavy after meeting the rigidity design requirements. The use ratio of carbon fiber composite materials in today's composite yachts has greatly increased, and some or even all use carbon fiber composite materials.
Marine engineering applications
It has been used in offshore island and reef buildings, docks, floating platforms, lighthouse towers, etc. abroad.
Carbon fiber composite materials are used in marine engineering construction due to their light weight, high strength and corrosion resistance, replacing traditional reinforced building materials in the form of tendons and structural parts to solve the problems of seawater eroding reinforced steel and long-distance transportation costs.
Regarding the application of carbon fiber composite materials in marine engineering, there is another type of repair and reinforcement of submarine pipelines or columns.
The repair of carbon fiber composite materials mainly uses carbon fiber cloth and epoxy resin and other high-strength and high-adhesion resin materials to adhere to the repair surface, so it is thin and light, high strength, good durability, convenient construction, adapt to different shapes, Has a significant advantage.
The use of carbon fiber composite materials for engineering repairs began in the 1980s. Mitsubishi Chemical Corporation of Japan took the lead in researching the mechanical properties and application of carbon fiber composite materials in engineering reinforcement. The initial research focus was on the use of carbon fiber composite materials to reinforce reinforced concrete beams, which later developed into the reinforcement and reinforcement of various civil engineering.
The excellent performance of carbon fiber composite materials makes it have broad application prospects in marine applications. Overall, compared with the mature applications in aerospace and other fields, the application of carbon fiber in the marine field is relatively late, and at the same time, the cost of carbon fiber The high side is also an important factor restricting its large-scale application. With the development of 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 the aspect of application traction. The healthy development of the chain.