Boiler Heat Exchanger , Boiler Spiral Fin Tube Economizer
,Economizer Module
Spiral Finned Tube Economizer
The economizer can be installed at the rear of exhaust gas
stovepipe to recovery exhaust gas heat,increase the electricity
output,lower the coal consumption.spiral finned tube economizer is
a new and efficient heat transfer equipment, which is a good
solution to the light tube economizer because of badly worn, short
life and other shortcomings.
Working Principles
Boiler economizer is kind of heat exchanger to heat the feed water
using the flue gas heat. The flue gas coming from the tube outside
is up and down cross-flow scrubbing the tube bundle, passing the
heat to the tube wall. The water is flowing from bottom to top, and
absorts the heat from the tube wall, and its temperature is getting
high. This way not only can countercurrent heat transfer to save
metal consumption, but also is good for water/steam to flow and
exhaust as well as decreasing corrusion. One more, this way works
well for dust cleaning.
Functions
The origin to use economizers is to heat the feed water using flue
gas waster heat so as to decrease the exhaust temperature and
increase boiler efficiency, save fuel consumption, which is how
economizer is named. If use boiler economizers, the feed water is
already heated here before coming to evaporation heating surface,
thus the heat absorted on evaporation heating surface as well as
the heating area is definitely decreased. Boiler economizers are
countercurrent placed. The working fluid average temperature is
lower than that of surnatured water, and apply mandatory flow to
create conditions for application of thin wall and small diameter
tubes. The whole structure is also very tight. Thus, the heat
transfer temperature difference and heat transfer co-efficient is
higher than that of convection evaporation tube bundle who has the
same smoke temperature range. That boiler economizers to replace
convection evaporation tube bundles can decrease metal consumption
by a large extend. Further more, the heated feed water comes to
steam drum, this way can decrease the temperature difference
between the water and the steam drum wall, and ultimately decrease
the thermal stress of the steam drum. Due to reasons above, now
economizer are the crutial parts of boilers. So we can summerize
the functions of economizers as below:
1. fuel saving: the economizers are placed at the rear part of
boilers. This way can decrease the smoke and gas temperatures, thus
to save fuels.
2.improve the working conditions of steam drums: due to
economizers, the feed water temperature is increased when entering
the steam drum. It reduces the temperature difference between the
feed water and steam drum wall as well as steam drum thermal
stress, so that it improve the working conditions of steam drums
and increase the service life.
3. reduce the boiler manufacturing cost: for the feed water is
heated in the boiler economizers. The use of low temperature spare
parts as boiler economizers to replace some of high-priced high
temperature water wall panels reduces the cost to manufacture
boilers.
Characteristics
a) Dimensional range
| Diameter | 6 – 102 mm(0.24 – 4.02 in.) |
| Wall thickness | 0.3 – 9 mm(0.01 – 0.33 in.) |
| Length | up to 25,000 mm(984 in.) |
b) Annealing conditions
• Hard
• Annealed conforming to standards (soft, half-hard, blank, etc.)
• According to customer specifications
Purpose
Using an economizer does not just prevent heat loss — it can also
extend the life of the boiler. Stresses from using cooler
temperature make-up water, known as “thermal shock”, can subject
wear and tear on the boiler’s structural integrity over time. This
hammering “shock” effect occurs as the boiler’s fixed tube-sheets
and fire-tubes rapidly contract from the sudden make-up of cooler
temperature water. However, when this water is pre-heated, the
temperature differential is far less extreme, putting less strain
on the boiler and giving it a longer operating life.
Quality Control
1. Fabrication area of 200,000 square meters
2. 150 Engineers
3. 600 Coded welders
4. 60 Licensed Inspectors(NDT Level-III instructors)
5. Class-A Licenses for Design and Manufacture Boiler
6. ISO 9001:2008 Quality System
7. ASME Certificate of Power Boilers
8. ASME 'S','U' and NB stamp authorization
Certificate
Company Introduction
Established in 1985,Zhangjiagang Hua Dong Boiler Co.,Ltd.(trading
as HD Boiler),produces power plant; industrial; waste heat; waste
incineration; biomass; organic heat carrier and electric steam
boilers. Coupled with a comprehensive range of heating surfaces, HD
Boiler brings to the market a unique service including boiler
design , fabrication, installation, maintenance and replacement of
boiler pressure parts.
