AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

What Are Boilers and How Are They Constructed?

Boilers are a common feature of many spaces, serving to heat fluids within a closed vessel to boil, heat, or vaporize them. While many boilers perform the same general role, the use of the end product may differ as heated fluids are taken for cooking, water heating, sanitation, central heating, power generation, and other applications. 

For most commercial boilers, the assembly creates pressure as water is heated through the burning of fuel. While some boilers rely on the transfer of steam for hot water delivery, others may rely on water that has been converted into steam. Regardless of which method is followed, the fluids will be relayed through pipes or radiators to reach different areas of a space or property. In terms of the main parts of a typical boiler, the most common assembly components include the combustion chamber, heat exchanger, expansion tank, burner, aquastat, backflow valve, supply line network, return line network, and circulator pump.

The combustion chamber of a boiler can be considered one of the most important parts, as it is where fuel is burned to create the heat necessary for operations to be carried out. Generally, materials like kerosene, heating oil, or liquid propane are used as a fuel source, and the chamber itself is made from cast iron so that the heat and pressure resulting from combustion can be withstood. Generally, the internal temperatures of boilers will reach upwards of several hundred degrees during operation, making it important that the assembly can maintain integrity under stress. As fuel is combusted, the heat exchanger transfers heat to the fluids within the boiler tank, allowing for fluid heating to be conducted without direct contact for safety. With the expansion tank, safety can be further ensured as the boiler is safeguarded from excessive pressure issues.

 Another major element of the boiler, the burner serves as the area where fuel and air is mixed before being ignited for combustion. To be activated, thermostats will relay electrical signals to actuate the processes of the burner when heat needs to be created. Upon activation, fuel will be transferred through pumps before being sprayed into the burner through a nozzle. With aquastats, the correct signal timing can be upheld so that the burner is started and stopped based on boiler fluid temperatures.

With parts like the backflow valve, supply lines, return lines, and circulator pump, the general flow of fluids in a boiler can be governed. For instance, the backflow valve serves to permit fluid flow in a single direction, featuring the ability to close off when fluids reverse. With each line, fluids can be supplied to distribution points or brought back to the boiler for reheating whenever necessary. Lastly, the calculator pump allows for heated fluids to be sent to various spaces and external systems.

If you are in the market for quality boiler parts, we have you covered here on After Market Industrials. Owned and operated by ASAP Semiconductor, we present customers access to over 2 billion new, used, obsolete, and hard-to-find items that have been sourced from thousands of leading manufacturers from across the globe. Take the time to explore our offerings as you see fit, and you can always request quotes for your comparisons through the submission of an online RFQ form as provided on our website. With our above and beyond dedication to quality control and export compliance, we proudly conduct business with AS9120B, ISO 9001:2015, and FAA AC 00-56B accreditation. See why so many customers steadily rely on us today when you get in touch with an industry representative.


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