Cast Iron Boiler Economizers
Cast iron boilers economizer is an energy-saving device installed in the tail flue of a cast iron boiler. Primarily made of cast iron, it recovers waste heat from the boiler’s exhaust gas to preheat the boiler’s feedwater.
- Fin Tube Material:Cast Iron
- Tube Sheet Material:Cast Iron
Product Details
What is Cast Iron Economizers?
A cast iron boiler economizer is an energy-saving device installed in the tail flue of a cast iron boiler. Primarily made of cast iron, it recovers waste heat from the boiler’s exhaust gas to preheat the boiler’s feedwater.
The core functions of a cast iron boiler economizer include:
Improving boiler efficiency: By absorbing heat from the flue gas, it lowers the exhaust gas temperature, reduces heat loss, and thus improves the overall thermal efficiency of the boiler by 5%-10%.
Protecting the boiler body: Preheating the feedwater reduces the temperature gradient entering the steam drum or water-cooled walls, lowers thermal stress, and extends the service life of the equipment.
Saving fuel and costs: It replaces part of the evaporative heating surface, reducing fuel consumption and optimizing system design.
Cast iron economizers typically consist of finned cast iron risers and connecting elbows, and are suitable for boiler systems with operating pressures not exceeding 2.5 MPa.
Because cast iron is corrosion-resistant but has a relatively weak capacity to withstand thermal stress, it is necessary to control the feedwater temperature and flow rate during operation, and to regularly clean accumulated ash to maintain heat exchange efficiency.
Looking for a cast iron gilled tube economizer partner?
Cangzhou Datang Steel Pipe Co., Ltd has over 100 years of experience in designing and manufacturing bespoke heat exchangers, economizers,including steam air heaters. We work with original equipment manufacturers and end-users to deliver top-class results based on our customer’s specific needs.
We are experts in fin design, as well as extended fin surfaces and their applications. This allows us to deliver customised air heater solutions for specific applications and environments.
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- Datasheet
- Drawing
- Certificates
Cast Iron Boiler Economizer Specifications and Applications
| Model/Parameter | Fuel Type | Application Scenario | Key Features |
|---|---|---|---|
| 4t Type | Coal | Industrial Boilers | Thermal efficiency ≥85%, tube spacing 1.5-2.5 (S/d) |
| smq Type | Coal/Oil/Biomass | Vertical/Horizontal Boilers | Reasonable structure, short installation cycle |
| Square Cast Iron Economizer | Coal/Gas | Power Plants/Chemical Plants | Corrosion-resistant, flue gas velocity 8-12m/s |
| Finned Economizer | Multi-fuel | Indoor/Outdoor Boiler Energy Saving | High-temperature resistant, weight 40kg |
Cast Iron Gilled Tube Finned Tube Economizer Heat Exchanger
Cast iron economizers, as the tail-end heating surface, form a technological distinction from steel tube economizers at the material level. Their fin structure is manufactured using cast iron casting technology, and the number of broken fins in a single tube must not exceed 5% of the total number of fins, with the overall number of broken fins limited to within 10% of the total. Compared to steel tubes, cast iron economizers exhibit stronger resistance to acid dew point corrosion in the low flue gas temperature range (typically below 400℃), but due to the limited thermal conductivity of cast iron, heat exchange efficiency needs to be compensated by increasing the fin area.
Cast Iron Economizer Parts Cast Iron Finned Tube
Cast Iron Economizers, using cast iron finned tubes, are the core components for improving heat exchange efficiency. Compared to traditional bare tubes, finned tubes significantly expand the heat transfer area by adding metal fins to the outside of the tube wall, allowing for more complete heat exchange between flue gas and feedwater. Cast iron is preferred for operating pressures ≤2.5MPa.
Cast Iron Economizer Parts Cast Iron Elbow
Cast iron elbows are a key connecting component in cast iron economizers, primarily used to change the flow direction of flue gas or water, achieving smooth turning connections between pipes. In cast iron economizers, 180° cast iron elbows are typically used, connecting a series of cast iron pipes with external ribs in series to form a horizontal or vertical pipe arrangement.<sup>1</sup> This design allows water to enter from one end of the lower pipe bank, flow horizontally to the other side, and then enter the upper pipe bank, forming a counter-current heat exchange with the downward-flowing flue gas, thereby efficiently recovering waste heat from the boiler’s tail flue.
