High strength central heating boiler economizer ISO9001 certification manufacturer inspection covers
1. Economizers (sometimes spelled as economisers) perform a key function in providing high overall boiler thermal efficiency by recovering low level (i.e., low temperature) energy from the flue gas to heat the boiler feedwater.
2. For each 40F (22C) that the flue gas is cooled by an economizer in a conventional boiler, the overall boiler efficiency typically increases by approximately 1%.
3. Economizers also reduce the potential of thermal shock and large water temperature fluctuations as the feedwater enters the steam drum or waterwalls.
H fin tubes Economizer Inspection
1. The major problem at the economizer section is low temperature corrosion and problems from gas side deposits.
2. Sliding and leaky expansion joints at the casing may allow accumulation of soot with severe acid attack.
3. Inspection of tubes bends by opening the inspection covers needs to be carried out to check these.
4. Uptake area may show cracked expansion bellows sign of acid corrosion.
5. General cleanliness of these areas indicates the combustion performance in boiler.
Economizers are used externally to boilers for further heat recovery. Economizers are found in the cooler gas zone and are fed with water temperatures around 116oC or 185oC depending upon whether the feed cycle includes high pressure feed heaters after the de-aerator.
The function of Boiler Economiser
1. The Economizer in Boiler works on the principle of Heat Transfer. Heat transfer usually takes place from high temperature to low temperature.
In the case of Boilers, flue gases or exhaust from the boiler outlet are at high temperature and water that needs to be preheated is at low temperature.
2. So, this temperature difference between water and flue gases helps to increase the feed water temperature.
3. Depending on the type of operations, design of Economisers can be smoke tube type or water tube type.
4. In smoke tube type flue gases are inside the tubes and water is on the shell side while in the water tube type, water is in the tube and flue gases are on the shell side.