|
About:
|
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements barring carbon (which sublimes at normal pressure), melting at 3,410 °C (6,170 °F; 3,683 K). It also has the highest boiling point, at 5,930 °C (10,706 °F; 6,203 K). Its density is 19.30 grams per cubic centimetre, comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten occurs in many alloys, which have numerous applications, including incandescent light bulb filaments, X-ray tubes, electrodes in gas tungsten arc welding, superalloys, and radiation shielding. Tungsten's hardness and high density make it suitable for military applications in penetrating projectiles. Tungsten compounds are often used as industrial catalysts. Tungsten is the only metal in the third transition series that is known to occur in biomolecules, being found in a few species of bacteria and archaea. However, tungsten interferes with molybdenum and copper metabolism and is somewhat toxic to most forms of animal life.
Features about sllicone tungsten
There is one kind of tungsten silicone-based shielding product, that made with tungsten, iron, bismuth or mixtures of these metals. The advantages of tungsten silicone-based shielding are base on the good performance of tungsten, iron, and bismuth. Tungsten silicone-based material offers the ability to put the shielding as close as possible to the source. In situations where space is limited, tungsten allows for the highest attenuation with the lowest shielding thickness and excellent radiation absorption. Iron provides a much less expensive option when space is not as limited. Bismuth is the middle ground offering excellent attenuation at a wide range of gamma energies. Tungsten silicone-based shielding can be formed into almost any size or shape. Tungsten carbide mechanical seals had been the preferred thing for several years. However, in recent times, they have been replaced by a strong competitor, silicon carbide seal faces. What could be the secret of this change of preference? Well, it is because of some prominent benefits.It does not mean that tungsten carbide seal faces have become obsolete. There are many applications where only Tungsten seal faces can work. This blog, not just rates rate a particular type of seal face higher to the other, but it gives a comprehensive analysis of the two. Thus, a user may pick the most suitable seals for the application. What is the primary reason for installing a seal? It is to keep the pollutants away and increase their life. The seal has two parts- one stationary and one rotating. The rotating or stationary part is made from either of the two materials that is used in the seal.
|
