High pressure boiler - PowerPoint PPT Presentation

About This Presentation
Title:

High pressure boiler

Description:

10 – PowerPoint PPT presentation

Number of Views:688
Slides: 14
Provided by: Suresh02061994
Tags:

less

Transcript and Presenter's Notes

Title: High pressure boiler


1
The Birth of The Water Tuber Boiler and
Christened as Steam Generator
  • P M V Subbarao
  • Professor
  • Mechanical Engineering Department

Generation of Unlimited Hopes for Development..
2
The Crisis
  • As industry developed during 19th century, so the
    use of boilers for raising steam became
    widespread.
  • Disastrous explosions sometimes occurred.
  • Boilers of that period consisted of heated
    pressure vessels of large diameter.
  • These are subject to internal pressure which is
    tensile stresses in the walls of the enclosure.
  • The existence and importance of stress, known as
    hoop stress is given by

3
Historical Development
  • 1766 William Blakey Patent on water in tube and
    fire outside.
  • Several tubes alternately inclined at opposite
    angles were arranged in the furnaces, the
    adjacent tube ends being connected by small
    pipes.
  • The first successful user of water-tube boilers,
    however, was James Rumsey, an American inventor,
    celebrated for his early experiments in steam
    navigation, and it is he who may be truly classed
    as the originator of the water-tube boiler.
  • In 1788 he patented, in England, several forms of
    boilers, some of which were of the water-tube
    type.
  • One had a fire box with flat top and sides, with
    horizontal tubes across the fire box connecting
    the water spaces.
  • Another had a cylindrical fire box surrounded by
    an annular water space and a coiled tube was
    placed within the box connecting at its two ends
    with the water space. This was the first of the
    "coil boilers".
  • Another form in the same patent was the vertical
    tubular boiler, practically as made at the
    present time.

4
(No Transcript)
5
John Stevens, 1804
  • The first boiler made of a combination of small
    tubes, connected at one end to a reservoir, was
    the invention of another American, John Stevens,
    in 1804.
  • This boiler was actually employed to generate
    steam for running a steamboat on the Hudson
    River, but like all the "porcupine boilers, of
    which type it was the first, it did not have the
    elements of a continued success.

6
1805 John Cox Stevens
  • Another form of water tube was patented in
    another form of water tube was patented in 1805
    by John Cox Stevens, a son of John Stevens.
  • This boiler consisted of twenty vertical tubes,
    1 internal diameter and 40 long, arranged in
    a circle, the outside diameter of which was
    approximately 12 inches, connecting a water
    chamber at the bottom with a steam chamber at the
    top.
  • The steam and water chambers were annular spaces
    of small cross section and contained
    approximately 33 cubic inches.

7
Julius Griffith, in 1821
  • The first purely sectional water-tube boiler was
    built by Julius Griffith, in 1821.
  • In this boiler, a number of horizontal water
    tubes were connected to vertical side pipes, the
    side pipes were connected to horizontal gathering
    pipes, and these latter in turn to a steam drum.

8
1822, Jacob Perkins
  • In 1822, Jacob Perkins constructed a flash boiler
    for carrying what was then considered a high
    pressure.
  • A number of cast-iron bars having 1 annular
    holes through them and connected at their outer
    ends by a series of bent pipes, outside of the
    furnace walls, were arranged in three tiers over
    the fire.
  • The water was fed slowly to the upper tier by a
    force pump and steam in the superheated state was
    discharged to the lower tiers into a chamber from
    which it was taken to the engine.

9
Joseph Eve, 1825
  • The first sectional water-tube boiler, with a
    well-defined circulation, was built by Joseph
    Eve, in 1825.
  • The sections were composed of small tubes with a
    slight double curve, but being practically
    vertical, fixed in horizontal headers, which
    headers were in turn connected to a steam space
    above and a water space below formed of larger
    pipes.
  • The steam and water spaces were connected by
    outside pipes to secure a circulation of the
    water up through the sections and down through
    the external pipes.

10
John M'Curdy
  • In the same year, John M'Curdy of New York, built
    a "Duplex Steam Generator" of "tubes of wrought
    or cast iron or other material" arranged in
    several horizontal rows, connected together
    alternately at the front and rear by return
    bends.
  • In the tubes below the water line were placed
    interior circular vessels closed at the ends in
    order to expose a thin sheet of water to the
    action of the fire.

11
Stephen Wilcox, 1856
  • Stephen Wilcox, in 1856, was the first to use
    inclined water tubes connecting water spaces at
    the front and rear with a steam space above.
  • Water-cooled enclosures.

12
Struggle for Understanding First Law of Steam
Generation
  • 1803 John Stevens A pseudo-water-tube design
    used in a steamboat.
  • 1822 Jacob Perkins Once-through boiler using
    cast iron bars.
  • 1856 Stephen Wilcox Inclined tube boiler with
    water-cooled enclosures.
  • 1880 Allan Stirling Bent tube connecting drums.

13
The Theory of Producing Steam
  • Water boils and evaporates at 100C under
    atmospheric pressure.
  • By higher pressure, water evaporates at higher
    temperature - e.g. a pressure of 10 bar equals
    an evaporation temperature of 184C.
  • During the evaporation process, pressure and
    temperature are constant, and a substantial
    amount of heat are use for bringing the water
    from liquid to vapour phase.
  • When all the water is evaporated, the steam is
    called dry saturated.
  • In this condition the steam contains a large
    amount of latent heat.
  • This latent heat in the dry saturated steam can
    efficiently be utilised to different processes
    requiring heat.
  • The steam boiler or steam generator is
    connected to the consumers through the steam and
    condensate piping.
  • When the steam is provided to the consumers, it
    condensate.
  • It can then be returned to the feed water tank.
Write a Comment
User Comments (0)
About PowerShow.com