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Last month, like a scene from an action movie, three men accompanied a young woman into a diamond show in Mumbai. However, their target diamond booth at Dalumi Israel has been collected in advance. When a man began to inspect the diamonds displayed, the woman quickly grabbed a box containing $1.4 million worth of diamonds into her bag. At that time, the sales staff of Dalumi had noticed the theft and immediately informed the organizers of the incident. It was too late when the organizers of the exhibition confirmed the matter through surveillance video. The four thieves have disappeared at the venue and fled to Hamburg, Germany through security. Since then, Interpol intercepted them at Dubai Airport and returned the diamonds to all of them.
This shocking thing caused a lot of waves in the diamond industry, but did not make the Islamic Diamond Exchange honorary chairman Shmuel Schnitzer very anxious. In response to a question from Hil Weissberg and Ora Koren of TheMarker Financial News, he said: "Theft of diamonds is not an easy task. Theft is only happening at the show to the general public. At the time of the event – ​​whether in Las Vegas, Hong Kong or India, the Israeli exhibitions were equipped with monitoring equipment, which is why the arrests were accurately captured at the Indian show because they were all photographed. On the one hand, the looting of diamond dealers often happens. This usually happens to diamond dealers doing business in the US and East Asia. This is indeed a problem."
theft
It seems that it is not just about the global financial crisis. In recent years, diamond dealers have encountered some new and unpredictable threats: synthetic diamonds. These diamonds are created under laboratory conditions and are just as true to the naked eye, but at a much lower cost. According to projections published by the Israel Diamond Institute website in 2008, approximately 500 million carats of synthetic diamonds are available each year, which are two-digit lower than natural diamonds.
Schnitzer is once again trying to calm the panic. “People are not scared at all.†He emphasized that these diamonds made in the laboratory are different. When a lady receives a diamond, she certainly does not want to be a counterfeit, but a real thing. Experts can see the difference in a second. So we didn't feel the pressure of competition, and we didn't feel any signs of a decline in sales. Synthetic diamonds have entered a different market segment – ​​I don’t want to say “gems†to avoid weakening them – but it can be said that the arrival of synthetic diamonds has indeed cost other jewels. â€
Still, this is indeed an area of ​​deception.
"Yes, that's why the law requires full disclosure. People care about this because they don't want to be sued."
There is only one option - to enter the industry
After two years of difficult times, the market began to show a more positive momentum in 2010: the export volume of diamonds rose. If everything goes as planned, then Schnitzer believes that within two years, exports will return to 2008 levels – polished diamond exports exceed $6 billion, rough diamonds More than $3.3 billion. The United States will always maintain its position as the main market for Israeli diamond exports. The situation of the United States in the crisis vortex has had a serious impact on the Israeli diamond industry. If the United States accounted for 65 percentage points of total diamond exports in 2007, it has now fallen to 35-40 percentage points. China, Hong Kong and India have gradually replaced their positions.
The 61-year-old Schnitzer breathed the dust of diamonds from the day he was born. His father, the late Moshe Schnitzer, was one of the founders of the Ramat Gan Diamond Exchange. Like other sons who grew up in the luxury of diamonds, Schnitzer later chose to enter his family business. But this is not over. His father has been president of the Israel Diamond Exchange for 26 years. Like his father, he also participated in diamond politics. After three presidents of the exchange and six years of chairmanship of the World Federation of Diamond Bourses, Schnitzer was awarded the Israel Diamond Industry Association (IDI) and the World Diamond Exchange Alliance ( WFDB) Lifetime Honorary Chairman.
Schnitzer said: "I grew up in such a family, there is only one kind of business in the world - diamonds. We have no other possibilities, just like my children. There is only one choice, then It’s just doing business. It’s as clear as the day. My father has been the chairman of the Diamond Exchange for many years, so there are always some politicians in the house. Fortunately, I like it very much and enjoy it. I got the diamond from my father. Passion."
“Everyone will be interested in this exhibitionâ€
A show that jewels into animals and flowers, "And Thou Shalt Breathe Life Into a Gem", opened last month at the Ramat Gan Diamond Museum. It will continue until the end of December. These gems are designed by artists from the German city of Idar-Oberstein, one of Europe's diamond and gemstone centers. The exhibition was supported by the German Ambassador to Israel Dr. Harald Kindermann. There are more than 140 exhibits at the show, worth tens of millions of dollars.
Shmuel Schnitzer, honorary chairman of the Israel Diamond Exchange and executive chairman of the Harry Oppenheimer Diamond Museum, explained that the show was from the 80s of the 20th century. The most important exhibition of this museum after the Kremlin Jewelry Show. He said: "This art has never been shown in Israel, because usually there are not many people in the world who are willing to bring art property here. The Israel Diamond Exchange and the Idar-Oberstein Exchange ( The relationship between Idar-Oberstein) is very good. Our industry is still very weak in the European market, because the Antwerp Diamond Center is geographically close to Europe. Therefore, strengthening the relationship with German diamond dealers will help strengthen the entire Israeli industry and Europe. Market connection."
According to Schnitzer, the museum expects to have about 3,000 visitors a month. “The museum is geared to the entire industry. Therefore, I think it is very important to highlight art and attract the public, especially in times of economic hardship.â€
The basic type of deep groove ball bearing consists of an outer ring, an inner ring, a set of steel balls and a set of retaining frames. There are two types of deep groove ball bearings: single row and double row, and the deep groove ball structure is also divided into two structures: sealed and open, open means that the bearing does not have a sealed structure, and the sealed deep groove ball is divided into dustproof seal and oil-proof seal. The dust seal cover is made of steel stamping, which simply prevents dust from entering the bearing raceway. The oil-proof type is a contact oil seal, which can effectively prevent the grease in the bearing from escaping.
The type code for single row deep groove ball bearings is 6, and the code for double row deep groove ball bearings is 4. Its structure is simple, easy to use, is the most common production, the most widely used type of bearing.
How it works
Deep groove ball bearings are mainly subjected to radial loads, but can also bear both radial loads and axial loads. When it is only subjected to radial loads, the contact angle is zero. When the deep groove ball bearing has a large radial clearance, it has the performance of angular contact bearing, can bear a large axial load, the friction coefficient of the deep groove ball bearing is very small, and the limit speed is also very high.
Bearing characteristics
Deep groove ball bearings are the most commonly used rolling bearings. Its structure is simple and easy to use. It is mainly used to bear radial load, but when the radial clearance of the bearing is increased, it has the performance of a certain angular contact ball bearing, and can bear the combined load of radial and axial directions. When the speed is high and thrust ball bearings are not suitable, they can also be used to bear pure axial loads. Compared with other types of bearings with the same specifications and dimensions as deep groove ball bearings, this type of bearing has a small friction coefficient and a high ultimate speed. However, it is not resistant to impact and is not suitable for bearing heavy loads. [2]
When the deep groove ball bearing is mounted on the shaft, the axial displacement of the shaft or housing can be limited within the axial clearance range of the bearing, so that it can be positioned axially in both directions. In addition, this kind of bearing also has a certain self-aligning ability, when it is inclined to 2′~10′ relative to the bore of the shell, it can still work normally, but it has a certain impact on the bearing life.
Structure and classification
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Bearing construction
Deep groove ball bearings have a simple structure and are easy to achieve high manufacturing accuracy compared with other types, so they are convenient for mass production in series, and the manufacturing cost is also low, and they are extremely commonly used. In addition to the basic type, there are various variant structures of deep groove ball bearings, such as: deep groove ball bearings with dust covers, deep groove ball bearings with rubber seals, deep groove ball bearings with stop grooves, deep groove ball bearings with large load capacity with ball notch, and double row deep groove ball bearings
Honorary Chairman of the Israel Diamond Exchange talks about diamond theft and synthetic diamonds
Shmuel Schnitzer, Honorary Chairman of the Israel Diamond Exchange