BERYLLIUM - A NUCLEAR METAL AND ITS MANUFACTURING PROPERTIES

Beryllium is a light metal and melts at about 1280*C. The metal is used as a moderator, reflector and neutron source. This is very reactive and forms compounds with the furnace atmospheres and refractories. Vacuum or inert gas are necessary during melting.

The cast metal is usually coarse grained and brittle, and powder metallurgy methods are employed in the fabrication of beryllium components.

Beryllium is a toxic metal. Its compounds are also very toxic. Safety measures are to be taken when handling this metal.

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ELECTRICAL COMPARATORS AND ITS WORKING

Electrical Comparators are used as a means of detecting and amplifying small movements of a work contacting elements. An electrical comparator consists essentially of a pick-up head or transducer for converting a displacement into a corresponding change in current and a meter or recorder connected in the circuit to indicate the electrical change, calibrated to show in terms of displacement. Generally, an amplifier is needed to provide the requisite sensitivity and to match the characteristics of different parts of the circuit. Electrical comparators can be classified according to the electrical principle used in the pick-up head. Most of the comparators use either a differential transformer, an inductance bridge, a strain gauge or a capacitor as a means of detecting movement of the gauging element. There are different types of electrical comparators. One kind called an electrolimit gauge is used to check or measure the outside diameter of a roll. The object to be checked is place

Advantages And Disadvantages Of Air Refrigeration System :

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THROTTLE GOVERNING OF STEAM TURBINES

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Mechinopedia For Mechanical Engineers

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