Hot pressure
The three basic types of low pressure boilers are fire tube boilers, water tube boilers, and cast iron sectional boilers. Fire tube boilers heat water by circulating hot gases through tubes, water tube boilers circulate water through tubes that are heated externally, and cast iron sectional boilers have multiple sections that heat water as it flows through them.
The difference between the two is that the Water tube boilers are safer and last much longer than the fire tube boiler. Their size is also larger and have a faster recovery time. However fire tube boilers have a low cost.
fire tube & water tube . high pressure and low pressure. low capacity and high capacity.
High pressure boilers operate at pressures above 15 psi, while low pressure boilers operate at pressures below 15 psi. High pressure boilers typically require more maintenance and inspection due to the higher pressures involved, while low pressure boilers are generally simpler and less expensive to maintain. Additionally, high pressure boilers are typically used in industrial applications where higher steam temperatures are required, while low pressure boilers are commonly used for heating and residential purposes.
A low-pressure boiler works by generating steam at a pressure lower than 15 psi (pounds per square inch). Water is heated in the boiler and turns into steam, which is then used for various applications such as heating or powering machinery. Low-pressure boilers are commonly used in buildings for heating systems and hot water supply.
High-pressure boilers can generate more steam at a higher temperature, which increases energy efficiency and reduces fuel consumption. They are also more compact in size and require less space compared to low-pressure boilers. Additionally, high-pressure boilers can achieve faster steam production and respond quickly to changes in demand.
Yes, a conventional boiler typically operates as a low-pressure boiler. Low-pressure boilers are designed to operate at pressures below 15 psi, which is common for residential heating systems. These boilers use water or steam to transfer heat, providing efficient heating for homes and buildings.
There are two aluminum tubes coming out of the compressor. The high pressure tube goes to the condensor in front of the radiator. The low pressure tube is the other tube, and the port has a black plastic cap over it, on the low pressure tube.
Water Tube BoilersSuitable for high steam pressure (above 500 psig) and temperature(to 1000 F) and large capacities exceeding millions of lb/h of steam.Extended surfaces can be used in waste heat applications to make the boilers compact if the gas stream is clean.Various types of fuels can be fired with ease including solid,liquid and gaseous. The water cooled membrane wall construction makes an excellent furnace.If the gas stream is dirty(as in MSW applications)provision can be made for cleaning using soot blowers or rapping mechanisms.Wide spaced tubes can be used at the gas inlet to minimize bridging of slag deposits and tube spacing can be decreased as the gas is cooled.This flexibility does not exist in fire tube designs.Superheaters if used can be located at the optimum gas temperature region shielded by any number of screen tubes.In fire tube boiler the choice is at the gas inlet or exit.Due to low water volume,the startup time is lesser and response to load changes is faster compared to fire tube boilers.If the gas pressure is high,say above 5 psig,the shell/casing design gets complicated and expensive though it can be done.Due to higher heat transfer coefficients surface area required is lesser and hence gas pressure drop is also lower.For multiple pressure designs as in gas turbine exhaust applications,water tube is the only choice.
Steam pressure does not exceed 103 Kpa (14.7 psi) in steam boilers, or as long as the temperature of the water does not exceed 121ºC (250ºF) or the pressure does not exceed 1103 kpa (160 psi) in hot water boilers 'Caesar Aborido BCIT'.
Draft tube is used to increase the pressure from the low turbine exit pressure to the pressure of the surrounding to which the fluid is rejected.Only reaction turbines require a draft tube as there is low pressure at the exit of the turbine,where as in an impulse turbine the pressure at the inlet and the exit is essentially the same, which is above the pressure to which the fluid is rejected and thus it require no draft tube.
It's not a switch. The high pressure runs from the compressor outlet to the orifice tube inlet, and the low pressure side runs from the orifice tube outlet to the compressor inlet.