9'5 Boilers operation

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9.5 Boilers operation

• The steps
• Fill the steam drum with water to the normal
  level
• Start the fan
• Light the burners
• Bring the boiler up to pressure
• Place the boiler online
• The prevention of typical boiler problems
• Including tube rupture, soot buildup in
  superheater
• and economizer tube, loss of water flow, flame
• impingement (frequent or sustained contact
  between
• and tube) , scale, impurities in steam or water,
  flame
• failure, and improper water level.

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9.6 Steam systems
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9.6 Steam systems
Steam (Saturated steam, Superheating steam,
Desuperhating steam ) As steam
flow from the boiler to the plant, it begins to
cools, condensate is formed. Slugs of condensate
water can damage equipment and lead to a
condition known as water hammer. So devise known
as steam traps are used to remove
condensate. Steam traps are grouped into two
categories Mechanical and thermostatic.
Mechanical steam traps include inverted buckts
and floats. Thermostatic traps include
bellows-type traps.
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9.6 Steam systems
.
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9.7 Steam system symbols
Steam system devices can be represented by the
symbols
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Summary

• Boilers, or steam generators, are devices that
• produce steam. They use a combination of
  radiant, conductive, and convective heat transfer
  methods to change water to steam.
• 2. Factors that affect boiler operation are
  density differences for internal circulation,
  pressure, temperature, and water level.
• 3. A fire tube boiler resembles a shell and tube
  heat exchanger in that it has a series of tubes
  enclosed in a shell. The tubes are heated by hot
  combustion gases and are submerged in water. Heat
  is transferred from the hot tube to the liquid
  through conduction and convection.

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Summary

• The most common type of large commercial boiler
  is a water tube boiler, which consists of a
  furnace that contains an upper and lower drum
  connected by tubes. Circulation through the
  system depends on density differences in the
  water in the various tubes. This type of boiler
  produces desuperheated and superheated steam.
• Steam system designed to reclaim steam traps to
  remove condensate. Steam traps are grouped into
  two categories Mechanical (inverted buckts steam
  trap and float steam trap) and thermostatic.
  Thermostatic steam traps are cheaper and selected
  more frequently than any other. They respond to
  the temperature differences between condensate
  and steam. A common thermostatic trap design is
  the bellows trap.

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