Steam Manifold boiler parts,steam Distribution header,CFB boiler
Manifold
General description
Boilers are made of boilers that hold water to produce steam and
boilers that generate heat by combustion. In order to transfer the
heat energy from combustion to water in the boilers, there must be
enough heat transfer area. In order to expand the heat transfer
area, boilers are developed into tube boiler to increase the heat
transfer area.
The water in these bundles must continuously circulate and absorb
heat energy and separate steam to the upper part of the box(tube),
and the water flows into the lower part of the box(tube), and
distribute to each bundle to continue to absorb heat in the
furnace. We call the upper and lower assembly boxes(tubes) boiler
headers.
Details
Header is not an independent component, but a part of water wall,
economizer, super-heater and other components, that is, there are
water wall header, economizer header, super-heater header. The
function of header is to collect or distribute steam and water
working fluid, reduce the pipeline of working substance
transportation and connection, and reduce the numbers of holes in
the drum, which is conducive to improving the safety performance of
the drum. The lower header of the water wall near the grate on the
both sides of the furnace wall prevents coking on both sides of the
grate, so it is called the coke-proof box.
The header is actually a thick diameter tube connected with many
heating surface pipes. It is made of seamless steel pipe and welded
flat heads(end caps) at both ends. There are many holes in the box
for welding or expanding the pipe. Both ends of the economizer tube
and the superheater tube are connected to the header, and the lower
end of the water wall is connected to the header. The upper end can
be connected to the header, and a few pipes can be drawn from the
head to the drum, or the upper end of the water wall tube can be
directly connected to the drum.
Large scale heat treatment furnace is used to supply the header for
integral heat treatment, which ensures to meet the requirements of
the header heat treatment very well.
Header hydraulic pressure test
The ambient air temperature when undergoing the hydraulic pressure
test is not less than 5 degrees, and the water temperature is
higher than the dew point and brittle transition temperature of the
tested workpiece material, but not higher than 70 degrees. The
recommended temperature f carbon steel is 21-40 degrees, and that
of alloy steel is 30-50 degrees. After the hydraulic pressure test,
the water inside the workpiece is drained, then the outer surface
of the workpiece is dried by compressed air, and then the inner
part of the workpiece is blown by the compressed air to ensure that
there is no water accumulated in the header.
Inner cleanliness of header
If there are straw hats, iron scraps and other debris in the
header, it is very easy to cause tube explosion and other shutdown
accidents when the power plant is running. Therefore, the
cleanliness of the header must be strictly controlled. After
drilling holes in the header, straw hats and burrs on the inner
wall of tube holes should be cleaned up by internal R wind milling
cutter, and the debris inside the header should be cleaned up in
time. When filling and welding, try to avoid dropping sundries
inside the header. When filling and chamfering after hydraulic
pressure, cover other tube joints to prevent iron chips from
falling in. In the final cleaning before leaving the factory, each
pipe joint is inspected by wire rope to prevent foreign body from
blocking the pipe joint. Compressed air blowing method is used to
clean up the debris inside the cylinder body. Endoscope is used to
check the inside of each pipe joint and the header to ensure that
the internal cleanliness of each header can meet the requirements.
