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  • Internal corrosion can take place inside boiler tubes under certain boiler water conditions.

  • The corrosive action eats into the tube metal, removing iron and resulting in thinner tube walls.

  • If this action is allowed to continue, certain tubes will fail and will rupture, as the thinner section of tube can no longer withstand the internal operating pressure.

  • The removed metal, products of corrosion, can also cause a problem, as this material now increases the total quantity of solids contained in the boiler water.

  • As we know, this can increase the probability of deposits and scale formation on the inside wall of the tubes.

  • So what are the conditions that cause corrosion and loss of metal inside the boiler drums and boiler tubes?

  • Well, there are basically three independent causes of corrosion, and they are Acid attack, which occurs when the boiler water is in an acidic condition, that is, low pH.

  • Caustic attack, which occurs when the alkalinity of the boiler water is too high.

  • The pH level is above about 10.5.

  • The presence of dissolved gases such as oxygen and carbon dioxide in the boiler water.

Internal corrosion can take place inside boiler tubes under certain boiler water conditions.

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B2 AU boiler corrosion tube water metal internal

lesson 5 || internal corrosion at boiler water control

  • 5 0
    陳建鴻 posted on 2024/11/16
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material

US /məˈtɪriəl/

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UK /məˈtɪəriəl/

  • noun
  • Cloth; fabric
  • Supplies or data needed to do a certain thing
  • Substance from which a thing is made of
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  • other
  • Fabric or cloth.
  • Information or data used for a particular purpose.
  • A substance from which something is made or can be made.
  • adjective
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  • Belonging to the world of physical things
  • Relating to physical matter or substance.

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basically

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scale

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  • Device that is used to weigh a person or thing
  • An instrument for weighing.
  • A sequence of musical notes in ascending or descending order.
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presence

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pressure

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increase

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condition

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occur

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section

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  • noun
  • Any of several parts or pieces that fit together to constitute a thing.
  • A part of a whole
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  • verb
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result

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