This is the story of South Africa’s discovery of the first diamond.
Coincidentally, in 1869, a shepherd boy picked up a sparkling "stone". He wanted to change his breakfast but was repeatedly rejected and mocked. Later he found a diamond dealer with a try. The businessman saw the original 83.5-carat rough diamond and was excited. He used all his homes, including a caravan, 10 cows, and 500 fat sheep, in exchange for the stone. This stone is the "Star of South Africa" ​​that has become famous all over the world. In 1870, the South African Star was cut, the largest of which was pear-shaped, weighing 47.75 carats and sold for $125,000. It was exhibited in Geneva in 1974 and was sold by a British Earl 500,000. The high price of the dollar was bought and given to the wife.
The discovery of the "Star of South Africa" ​​is also an important turning point in the South African economy. The "Star of South Africa" ​​set off a diamond frenzy, workers abandoned the machine tool, merchants closed the store... A large number of Taobao people poured into South Africa, they hungrily rushed to the banks of the Orange River and the Var River, trying to get rich overnight. This frenzy quickly led South Africa to move from a traditional agricultural country to an advanced industrial country. The "Star of South Africa" ​​is indispensable.
In 1884, the world's most abundant gold mine was discovered in Transvaal. Centered on Johannesburg, it extends to the east and west, forming a curved golden vein that is tens of kilometers long. A wave of gold rushing began, and gold rushers poured into the mining area from all over the world, and gold sand mining blossomed everywhere. Today, there is a very famous tourist attraction near the old town of Johannesburg, the Golden City, which was built on the gold mine of the year. Visitors can go down to a few kilometers of mines and experience the gold rush of the year. In the historical photos on display, you can see Chinese miners in ragged clothes and scorpions.
The discovery of diamonds and gold has had a major impact on the history of South Africa. The population of Europe in South Africa has rapidly increased to 300,000. Johannesburg was originally a desolate village, and its population exploded overnight. It became one of the four famous cities in Africa at that time. Of course, it is the discovery of diamonds and gold mines that triggered the most famous war in the history of South Africa, the British-British war.
Today, mineral resources such as diamonds and gold have become important economic pillars in South Africa. South Africa is one of the five largest mineral countries in the world. There are more than 70 kinds of minerals that have been proven and mined. In addition to the well-known diamonds and gold, manganese, vanadium, chromium, titanium, aluminosilicate, asbestos, coal and other reserves. They are extremely rich.
Some people say that God is fair. He gave poverty to Africa and buried a lot of minerals and energy at the feet of Africans. Of course, God did not think that these wealth, which should have belonged to Africa, brought the suffering of the African people for hundreds of years. Dozens of African countries, including South Africa, suffered from an unsalable colonial history, and a large amount of underground resources were predatory to the European countries by Western countries. Undoubtedly, the civilization and rise of Europe is based on the blood output of Africa. Even today, many of Africa's energy is firmly controlled by Westerners.
In fact, not only Africa, Asia, and many countries in the Americas are victims of this colonial history.
According to different methods of use, winches can be divided into four types: manual winches, electric winches, pneumatic winches, and hydraulic winches. At present, the largest marine hydraulic winch is 350T, and the weight of the equipment reaches 150T.
According to the reel form, it is divided into single reel and double reel.
According to the reel distribution, there are parallel double reels and front and rear double reels.
The main technical indicators of hydraulic winches include rated load, supporting load, rope speed, rope capacity, etc.
A winch is a light and small lifting device (see hoisting machinery) that uses a reel to wind a wire rope or chain to lift or tow heavy objects, also known as a hoist. The winch can be used alone or as a component of machinery such as lifting, road construction and mine hoisting. It is widely used because of its simple operation, large rope winding volume and convenient displacement. The winch is also known as the hoist. The product has high versatility, compact structure, small size, light weight, heavy lifting, and convenient transfer. It is widely used in construction, water conservancy projects, forestry, mines, docks, etc. for material lifting or flat towing, and can also be used as modern electronic control Supporting equipment for automatic operation line.
According to the power, the winch is divided into three categories: manual, electric and hydraulic.
The transmission mechanism of the handle rotation of the manual winch is equipped with a stopper (ratchet wheel and pawl), which can keep the heavy object in the required position. The manual winch used for assembling or lifting heavy objects should also be equipped with safety handles and brakes. Manual winches are generally used in places where the lifting capacity is small, the facilities are poor, or where there is no power supply.
Electric winches are widely used in places with heavy work and large traction requirements. The electric motor of the single-drum electric winch (pictured) drives the drum through the reducer, and a brake is installed between the electric motor and the input shaft of the reducer. In order to meet the needs of lifting, traction and rotation, there are also double-drum and multi-drum winches. Generally, a winch with a rated load lower than 10T can be designed as an electric winch.
The hydraulic winch is mainly a winch with a larger rated load. Generally, the winch from 10T to 5000T is designed as a hydraulic winch. The winch can be divided into:
Marine winches: Marine winches can be divided into drag winches, mooring winches, anchor winches, traction winches, etc.
Engineering winch: Mainly used in engineering, with functions such as hoisting and hoisting as the main function.
Mine winches: divided into hoisting winches, dispatching winches, shaft sinking winches, column return winches, rake mine winches, column return winches, etc.
Cable winch: mainly used when laying cables.
Lifting And Traction Winch,Pneumatic Winches,Hydraulic Winches,Electric Winches
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