VINYL PLASTICS - A TYPE OF THERMOPLASTIC

This is the general name of a large group of plastics usually polyvinyl-chloride (PVC) is the most frequently used of this group. This is a very clear, transparent plastics, easily colored, resistant to most chemicals and very water repellant. It can stand outdoor exposure and is quite abrasion resistant, but it has low tensile strength.

PVC can be extruded as wire insulation, chemical tubing and refrigerator door gaskets. Coating of fabrics of all kinds for industrial uses (such as tents and tarpaulin-type cover) is a major use of PVC.

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Advantages And Disadvantages Of Air Refrigeration System :

Advantages Of Air Refrigeration : 1. The refrigerant used namely air is cheap and easily available. 2. There is no danger of fire or toxic effects due to leakages. 3. The weight to ton of refrigeration ratio is less as compared to other systems. Disadvantages Of Air Refrigeration : 1. The quantity of Refrigerant used per ton of refrigeration is high as compared to other systems. 2. The COP of the system is very low. Therefore running cost is high. 3. The danger of frosting at the expander valves is more as the air contains moisture content.

ELECTRICAL COMPARATORS AND ITS WORKING

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THROTTLE GOVERNING OF STEAM TURBINES

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Mechinopedia For Mechanical Engineers

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