Because rare metals are important in modern industry, they are sometimes separated from non-ferrous metals and become a single class. And juxtaposed with ferrous metals and non-ferrous metals, it becomes the three major categories of metals. Non-ferrous metals are the basic materials for the development of the national economy. Most industries such as aviation, aerospace, automobile, machinery manufacturing, power, communications, construction, and home appliances are based on non-ferrous metal materials. With the rapid advancement of modern industry, agriculture and science and technology, the status of non-ferrous metals in human development is becoming more and more important. It is not only an important strategic material in the world, an important means of production, but also an important material for indispensable consumption materials in human life. Over the past 50 years since the founding of the People's Republic of China, China's non-ferrous metal industry has made brilliant achievements. It has built a large number of non-ferrous metal mines, smelting and processing enterprises, and established geological, design, survey, construction and other construction units and scientific research, education, environmental protection, information and other businesses. Units and materials supply and marketing and import and export trade units have formed an industry with a relatively rational layout and a relatively complete system. In 2006, China's non-ferrous metal industry maintained a good development trend as a whole. The output of non-ferrous metal products continued to grow, and the economic benefits of enterprises rose sharply. The total output of 10 non-ferrous metals reached 19.17 million tons, ranking first in the world for five consecutive years. The national non-ferrous metals enterprises above designated size achieved the main business income, profits and taxes, and profits reached 134.7 billion yuan, 163.1 billion yuan, 110 billion yuan respectively, and the total import and export trade of non-ferrous metals exceeded 65 billion US dollars. The annual gold output was 240.08 tons, the highest level in history. In 2007, China's non-ferrous metal industry fixed asset investment continued to maintain rapid growth. Among them, the investment in fixed assets in the field of non-ferrous metal mines increased significantly. The fixed assets investment was 35.5 billion yuan, an increase of 54% over the previous year, accounting for 22% of the total investment in fixed assets. The investment in fixed assets in the field of non-ferrous metal alloy manufacturing and rolling processing increased rapidly. The fixed assets investment was 42 billion yuan, an increase of 33% over the previous year, accounting for 26% of the total investment in fixed assets. The fixed assets investment in the non-ferrous metal smelting field was 73 billion yuan, an increase of 15% over the previous year, accounting for 46% of the total fixed assets investment completed by the industry.
DIN 965 countersunk head screws are a type of fastener that is commonly used in a variety of applications. They are designed to be driven into a pre-drilled hole and are secured with a countersunk head. The head is designed to sink flush with the surface of the material being fastened. These screws are available in a variety of materials, thread sizes, and lengths. They are commonly used in woodworking, metalworking, and other applications.
Countersunk head screws are a type of fastener that are commonly used in woodworking and metalworking projects. They have a flat head with a conical shape that tapers down to a smaller diameter at the top. This design allows the screw to sit flush with the surface it is being fastened to, creating a clean and neat appearance. Countersunk Head Screws,Hex Socket Countersunk,Hex Socket Countersunk Head Screw,Countersunk Cap Screw Taizhou Wanluo Hardware Products Co., Ltd. , https://www.wlhardware.com
The head of a countersunk screw typically has a single slot or a cross-shaped recess, known as a Phillips or a slotted head respectively, which allows for easy installation using a compatible screwdriver or bit. The countersunk shape also enables the screw to be easily countersunk into the material, meaning it can be driven below the surface to create a smooth and level finish.
Countersunk head screws are available in various materials, such as stainless steel, brass, or zinc-plated steel, providing different levels of strength, corrosion resistance, and aesthetic appeal. They come in different sizes and lengths, allowing for versatility in different applications.
In summary, countersunk head screws are fasteners with a flat head that tapers down to a smaller diameter, allowing them to sit flush with the material's surface. They are commonly used in woodworking and metalworking projects, and are available in various materials, sizes, and lengths.