How optic fibers are manufactured?

How does a large glass cylinder become a tiny thread of ﬂ exible glass?

The tiny ﬁlament of glass at the core of a length of optical fiber starts out as two tubes. These tubes are made from fused quartz glass, which is mainly silica to give it ﬂexible properties. First the glass tubes are dipped in corrosive hydroﬂuoric acid to remove any oily residues, they are then placed in a pair of lathes that spin and heat both tubes with a hydrogen and oxygen ﬂame. When the tubes turn white they are nearing peak temperature and at 2,000°C the tubes melt together to form one longer tube.

This longer tube is placed in another lathe where it is turned and heated by a burner before being injected with chemical gases containing liquid forms of silicon and germanium. The heat and gases cause a chemical reaction that leaves a ﬁne white soot inside the tube. As the burner travels up and down the length of the tube the soot fuses to create a solid glass core. The outer glass tube will form the cladding around the core.

Heating softens the tube and the new glass inside until the tube collapses in on itself. You now have a solid rod called a preform. To thin the preform, it is placed vertically in a drawing tower. This heats one end of the rod to 2,000°C until the glass becomes a honey-like consistency. As the glass melts it stretches under its own weight and becomes a very tall, thin glass fiber.

Pulleys and lasers are used to measure the precise tension and diameter of the ﬁbre, which should be just 125 micrometres thick. The ﬁbre is then passed under an ultraviolet lamp to bake on a protective outer jacket. The ﬁnished optical ﬁbre is then rolled onto massive drums.

Comments

How Energy conversion from coal is done?

Single generator sets of over 600 MW are now used in the UK, though there are many smaller generators in use. A 600 MW generator can supplythe average needs of over 1 million UK households. Three or four such generators are typically installed in a single large coal-fired station which isoften sited close to a coal mine, away from the city dwellers who consume the electricity. Such generators are usually driven by a compound arrangement of highpressure, intermediate-pressure and low-pressure turbines, increasing in size as the pressure decreases. Modern turbines rotate in a speed range from 1500 to 3500 r.p.m., usually 3000 r.p.m. for the UK’s 50 Hz system. For large coal-fired plant the steam pressure could be 25 megapascals (MPa) with steam temperatures of 500–600 °C to improve the thermodynamic efficiency. In nuclear reactors, which operate under less demanding conditions, the steam is superheated to about 5 MPa and 300 °C. Modern water tube boilers are complex and have ...

Why swiss Bank is Famous for Black Money?

Hello everyone, here we are going to talk about Swiss Bank. When a person hear the name of this bank the only thing that come to our mind is Black Money. When any kind Fraud occur we hear the name of Swiss Bank and Government also tell that he is going to bring all the black money from Swiss Bank. Swiss Bank is located in Switzerland and was established in 1872 as Basler bankverein. According to Switzerland banking law bank officials cannot disclose the name of account holder name unless and until Swiss court order them. Swiss court give the order only when there is a criminal charge on account holder name for example money laundering, fraud etc. The account in Swiss Bank are secretive account. Anyone who open a bank account in Swiss Bank he has to complete his KYC as normal bank do. But they never reveal the identity and address of account holders name. The account is in coded digits. In bank statement the account holder name is also not disclosed to any one. Here Swi...

How Bulletproof glass works?

Shattering the science behind what makes the breakable unbreakable Bullet-resistant glass works by absorbing a bullet’s kinetic (movement) energy and dissipating it across a larger area. Multiple layers of toughened glass are reinforced with alternated layers of polycarbonate – a tough but ﬂ exible transparent plastic which retains the see-through properties of glass. As a bullet strikes the ﬁ rst glass layer, the polycarbonate layer behind it forces the glass to shatter internally rather than outwards. This process absorbs some of the bullet’s kinetic energy. The high velocity impact also ﬂ attens the bullet’s head. Imagine trying to pierce through a sheet of cotton with the top end of a pencil. It would be very difﬁ cult compared to using the sharp pointed end. The same principle applies here. The ﬂ at-headed bullet struggles to penetrate the layer of polycarbonate. As the bullet travels through each layer of glass and polycarbonate, the process is repeated until it no l...

Knowledge N Fact4u

Search This Blog