Hot selling economiser bare tube type optimize economiser design
for better performance
Bare tube Economiser
1. Economiser performs a key function in providing high overall
boiler thermal efficiency by recovering the low level energy from
the flue gas before it is exhausted to the atmosphere. Economiser
recovers the energy by heating the boiler Feedwater.
2. Economiser are basically tubular heat transfer surfaces used to
preheat boiler feed water before it enters the steam drum or
furnace surfaces.
3. Economiser reduces operating costs or economise on fuel by
recovering extra energy from the flue gas. Economisers also reduce
the potential of thermal shock and strong water temperature
fluctuations as the feed water enters the drum or waterwalls.
4. Increasingly stringent environmental regulations limiting
nitrogen oxides and sulfur dioxide emission can also affect
economizer design.
5. The gas-side heat transfer coefficient is much less than water
side heat transfer coefficient. To compensate this, outer surface
of the tubes may be finned to increase the surface area of heat
transfer.
6. The ultimate goal of economizer design is to achieve the
necessary heat transfer at minimum cost. A key design criterion for
economizer is maximum allowable flue gas velocity. Higher velocity
provide better heat transfer and reduce capital cost.
Spare Parts Tubular Economiser Brief Introduction
1. After producing steam, the flue gas comes out from the system.
Some heat energy remains in the flue gas when it goes out.
2. If we cannot utilise this heat energy, it gets lost.
3. Boiler economiser is a device which uses a portion this remained
energy of the flue gas to heat up inlet water (feed water) to the
boiler.
4. Since the heat energy is given to the water before it gets fed
to the boiler, the requirement of fuel for producing steam is
optimised. Because of that, we call this device as economiser.
Conclusion
1. The most common and reliable economiser design is the bare tube,
in-line, cross flow type. When coal is fired, the flyash creates a
fouling and erosive environment.
2. The bare tube, in-line arrangement minimizes the likelihood of
erosion and trapping of ash as compared to staggered arrangement.
3. It is also easiest geometry to be kept clean by sootblowers. To
reduce capital costs, most boiler manufacturers have built
economizers with a variety of fin types to enhance the controlling
gas-side heat transfer rate.
4. Fins are inexpensive parts which can reduce the overall size and
cost of an economiser. However, successful application is very
sensitive to the flue gas environment.
5. Surface cleanability is key concern. In selected boilers, such
as coal-fired units, extended surface economisers are not
recommended because of the peculiar flyash characteristics.
6. Stud fins have worked reasonably well in gas- fired boilers.
However, stud finned economisers have higher gas side pressure drop
than a comparable unit with helically-finned tubes.
Specification
| Description | Boiler economizer |
| Material | Alloy steel, Carbon steel, SA210C ,SA213T22, etc |
| Material standard | ASTM, EN or ISO etc. |
| Dimension | Customization |
| Weight | Min: 10 ton
Max.:1000 ton |
| Smelting Process: | EF+LF + VD |
| Process | Material→Ingot → Hot/Cold-Rolling→ Heat treatment (Normalizing+
tempering) → Inspection →rough machining→UT →2nd Heat treatment
→finishing machining →Inspection |
| UT standard | ASTM A388 or EN10228, etc |
Detailed pic of polishing
