The basic knowledge of maintenance-free lead-acid battery people often say that the regular name of the maintenance-free battery is called the valve-controlled sealed lead-acid battery. Valve controlled sealed lead-acid battery from the appearance including, shell, valve cover, wiring terminals. The sealing material around the terminal is red and black (or blue) respectively to indicate the positive and negative terminals. The 12V battery is divided into 6 independent isolated cells, each cell has a positive plate group and a negative plate group connected by their own bus conductor. The plate of the lead-acid battery is like the structure of reinforced cement, which is formed by coating (or rolling) active substances on the sieve skeleton of the alloy wire: the material on the positive plate is lead dioxide (PbO), and the material on the negative plate is velvet lead (Pb). Each of the positive and negative 2.
The plates are separated by porous microfiber material (or filled with silica gel material), which adsorbs sulfuric acid (HSO) electrolyte.
This fiber material (or silica gel material) is the liquid and gas transport channel during the electrochemical reaction process, it is tightly assembled with the positive and negative plate groups to form a 2V cell. Since the plates of lead-acid batteries inevitably produce hydrogen and oxygen when they are being charged, pressure builds up in the cell when they produce too much and are not ready to melt into water. In order to ensure the normal and safe work of the battery, each single cell has its own air overflow valve, when the pressure is excessive, let the gas escape automatically. Compared with the battery tank filled with full of electrolytic liquid inside the battery, the valve controlled sealed lead-acid battery contains only a small amount of electrolyte inside, also called: the lean battery. However, due to the design of the electrolyte has a certain redundancy, and under the protection of the overflow, as long as the valve pressure be reasonable used, the water loss is minimal which is caused by the gas escape, and the valve control battery electrolyte in the life process of the basic need not supplement, so the valve control sealed lead-acid battery is also known as maintenance-free battery.
Maintenance Free Battery,Maintenance Free Car Battery,Sealed Maintenance Free Battery,Maintenance Free Lead Acid Battery Jinhua Juxing Power Supply Co., Ltd , https://www.poweriderbattery.com
In the past two decades, the development of China's manufacturing industry has been extremely rapid, and the machine tool industry has been among the largest machine tool manufacturers in the world with incredible speed. Bringing this scene of prosperity is even more glorious: In 2002, China's machine tool consumption reached 5.696 billion U.S. dollars, ranking first in the world. Since then, China has become the world's largest consumer of machine tools for 10 consecutive years. In 2009, China’s manufacturing output value surpassed Japan to become the world’s second largest manufacturing country. In 2009, China’s machine tool industry’s total industrial output value and sales revenue exceeded Japan’s. In Germany, it has for the first time leapt to the world's largest machine tool manufacturing country; in the 2010 Global Manufacturing White Paper, it ranked third among the “Top 10 Manufacturing Powerhouses in the World†list. Such a huge market with unlimited development potential is like a huge magnet, attracting all the machine tool companies in the world to plunge into the market.
With the entry of a large number of multinational companies, the Chinese machine tool market has undoubtedly evolved into an invisible battlefield filled with smoke. Here, all companies stand out in the competition with local competitors and other multinational companies. They fight technology, fight service, fight for others, and fight for strategies.
According to statistics from the General Administration of Customs of China, in the first half of 2013, China imported 38,426 sets of metal processing machine tools, a year-on-year decrease of 22.3%; the import volume was 5.251 billion US dollars, a year-on-year decrease of 17.2%; the average unit price was 136,700 U.S. dollars per unit. Increased by 6.6%. Statistics show that in the month of June, China imported 6,362 metal processing machine tools, a decrease of 3.7% from the previous month, and the import amount was US$849 million, a year-on-year increase of 14.1%; the average unit price was US$133,400/unit.
From the above data, we can see that since the impact of the global economic crisis last year, the Chinese machine tool industry has not fully recovered this year. As industry insiders say, industry demand is still weak, and the situation is still low, but compared with last year, The decline has gradually eased.
In advanced technology, we are still in the stage of follow-up. China's CNC machine tools still have a gap in terms of speed and precision. The same specifications of the product, foreign machine tool speed is probably three times the domestic machine tools, accuracy is also close to an order of magnitude higher. The domestic CNC system has obvious gaps from the advanced world level in terms of high-speed, high-precision, five-axis processing and intelligent functions. Therefore, to achieve a full-scale manufacturing industry, high-end numerical control equipment still has to overcome difficulties. So, what is the development of other countries or regions that are also deeply affected by the economic crisis? From the following sets of data can be glimpsed.
According to the statistics from the American Manufacturing Technology Association, from January to May 2013, the U.S. metal processing machine tool orders were 2.09 billion U.S. dollars, a year-on-year decrease of 6.9%. Among them, orders for metal cutting machine tools were 1.87 billion U.S. dollars, down 7.7% year-on-year; orders for forming machine tools were 210 million U.S. dollars, up 0.2% year-on-year.
In Japan, according to the statistics of the Japan Machine Tool Industry Association, in the first half of 2013, the total orders of eight major machine tool manufacturers in Japan were 219.43 billion yen, a year-on-year decrease of 17.1%. The eight machine tool manufacturers include Mori Seiki Co., Ltd., OKUMA, Makino Manufacturing Co., Ltd., Osaka Kogyo OKK, Toshiba Machine Co., Ltd., Jinshang Jietete, Toyota Mechanic, and Mitsubishi Heavy Industries.
According to statistics, the eight domestic machine tool manufacturers needed orders for 74.22 billion yen in the first half of the year, a decrease of 21.1% year-on-year, and orders for external demand were 145.21 billion yen, a decrease of 15.0% year-on-year. The proportion of foreign demand increased by 1.7 percentage points to 66.2%. It is not difficult to see that the situation of the machine tool industry in the United States and Japan is similar to that in China.
The huge domestic market demand is a positive factor in stimulating technological progress. At the same time, as foreign products continue to enter the Chinese market, it also stimulates the upgrading of domestic machine tools, and the elimination of Taiwan's competition rules also promotes the development of machine tool companies. It is estimated that by 2020, a large number of high-end CNC machine tools needed in various fields of manufacturing will be domestically produced.