Low-pressure boilers operate at a lower pressure and reach lower temperatures than high-pressure steam boilers. Water in low-pressure boilers is not heated beyond 250ºF, and the steam pressure does not exceed 15 psi (pounds per square inch).
One of the biggest issues related to natural gas explosions is that in the industrial world, people just don’t understand that natural gas piping repairs are different from other piping repairs.
Three-pass steam boilers are so-called because the combustion gases that are produced inside them in the burner go round a circuit that has three parts before leaving it:
Shell boilers may be defined as those boilers in which the heat transfer surfaces are all contained within a steel shell. Shell boilers may also be referred to as "fire tube" or "smoke tube" boilers because the products of combustion pass through the boiler tubes, which in turn transfer heat to the surrounding boiler water.
The vertical type and horizontal type are the two main types of boiler. The vertical gas-fired boiler has small volume and is suitable for small workshops or small production enterprises. It is often used in the fields of hot water and heating. The horizontal gas-fired boiler has larger volume with a wider application range than the vertical gas-fired boiler.