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  1. 1 point
    Arun Gupta

    RefineryFlow[1].png

    From the album petroleum

  2. 1 point

    From the album petroleum

  3. 1 point
    Arun Gupta

    1558-004-35CCD8B2[1].jpg

    From the album petroleum

  4. 1 point
    Outstanding properties of teflon:- Uses of Teflon and Properties 1. Chemicals includes ozone,chlorine,acetic acid ammonia,sulphuric acid and hydrochloric acid. The coatings are affected by molten alkali metals and highly reactive fluorinating agents. 2. It is weather and UV resistant Teflon 3. It has excellent optical properties 4. It is non stick Very few solid substances can permanently stick to a Teflon coating, where as tacky materials may show some adhesion, almost all substances release easily from the coating. 5. It has outstanding performance at extreme temperatures. Teflon can temporarily withstand temperatures of 260C and cryogenic temperatures of -240C and will then also have the same chemical properties.It has an initial melting point of 342C (+- 10C) temperature. 6. It has low coefficient of friction. Coefficient of friction is the ratio of the force required to make two surfaces slide over each other. A low coefficient of friction equals low resistance and smooth operation. Thus there is no difficulty in sliding one surface against another. The coefficient of friction of Teflon is generally in the range of 0.05 to 0.20, depending on the load, sliding speed, and type of Teflon coating used. 7. Teflon finishes are both hydrophobic and oleophobic, which makes cleanup easier and more thorough. 8. Over many different frequencies, low dissipation factor and high surface resistivity teflon has a high dielectric strength. The high voltage that the insulating material can withstand before it breaks down is its dielectric strength . In addition to it teflon has a low dissipation factor; that is the percentage of electrical energy absorbed and lost when current is applied to an insulating material. A low dissipation factor indicates that the absorbed energy dissipated as heat is low.The high surface resistivity indicates the electrical resistance between opposite edges of an unit square on the surface of an insulating material. Uses of Teflon:- The various market applications of Teflon include : Computer pin belt 1. In electronics industry it is used on account of its insulation property in wires and system components.Also used because of its outstanding electrical performance and durability. Uses for coating 2. Used for metal finishing, paints and coatings,as flour additives can be added to reduce the wear and tear on load-bearing surfaces. For example in inks and lithographic printing, thermoplastics and molded gears, protective industrial surfaces, lubricants to thicken, sterile packaging, etc. Uses as automobile air bags 3. In optical devices, as it can be used as clear coating, requiring a low refractive index and still perform in aggressive chemical environments over a wide range of use temperatures and light waves (UV-IR). For example, it is found in lightweight surgical lamps, photovoltaic cell glazing, etc. 4. In automobiles it finds its uses as airbag systems, fuel hose permeation barrier, fuel system, chassis, brake systems, oil filter, etc. 5. Used as nonstick coating on cooking devices like pans, oven , tawa as it is nonstick and exceptional performance at high temperatures.
  5. 1 point
    prad

    nice job dear

    nice job dear
  6. 1 point
  7. 1 point
    The most basic model for insulation on a pipe is shown above. R1 and R2 show the inside and outside radius of the pipe respectively. R3 shows the radius of the insulation. Typically, when dealing with insulations, engineers must be concerned with linear heat loss or heat loss per unit length. Generally, the heat transfer coefficient of ambient air is 40 W/m2K. This coefficient can of course increase with wind velocity if the pipe is outside. A good estimate for an outdoor air coefficient in warm climates with wind speeds under 15 mph is around 50 W/m2K . Eqn(1) The total heat loss per unit length is calculated by: Eqn(2) Figure 3: Heat Loss vs. InsulationThickness Since heat loss through insulation is a conductive heat transfer, there are instances when adding insulation actually increases heat loss. The thickness at which insulation begins to decrease heat loss is described as the critical thickness. Since the critical thickness is almost always a few millimeters, it is seldom (if ever) an issue for piping. Critical thickness is a concern however in insulating wires. Figure 3 shows the heat loss vs. insulation thickness for a typical insulation. It's easy to see why wire insulation is kept to a minimum as adding insulation would increase the heat transfer.
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