【Basic Knowledge 24】Classification of Boilers (Prize Quiz)

Low-pressure boilers, medium-pressure boilers, sub-high-pressure boilers, high-pressure boilers, sub-critical boilers, super-critical boilers.

Based on the steam pressure generated by the boiler, boilers can be classified into 6 categories. (1) Low-pressure boilers are those with a pressure of less than or equal to 2.45 MPa; their steam temperature is usually at the saturation temperature or no higher than 400°C. (2) Medium-pressure boilers, boilers with an outlet steam pressure of 2.94–4.90 MPa. For the current parameter ranges of power station boilers in our country, the outlet steam pressure for medium-pressure boilers is specified at 3.83 MPa, with a steam temperature of 450°C. (3) High-pressure boilers, boilers with an outlet steam pressure of 7.84–10.8 MPa. For the current parameter series of power station boilers in our country, high-pressure boilers have an outlet steam pressure of 9.81 MPa, with the outlet steam temperature typically being 540°C. (4) Ultra-high-pressure boilers are those with an outlet steam pressure of 11.8–14.7 MPa. For the current parameter ranges of power station boilers in our country, ultra-high pressure boilers are specified to have an outlet steam pressure of 13.7 MPa and a steam outlet temperature of 540°C; in some cases, this temperature is 555°C. (5) Subcritical pressure boilers are those with an outlet steam pressure ranging from 15.7 to 19.6 MPa. For the current parameter ranges of power station boilers in our country, subcritical pressure boilers are specified to have an outlet steam pressure of 16.7 MPa, with an outlet steam temperature of 540°C or 555°C; in a few cases, it is 570°C. (6) Supercritical pressure boilers are those whose outlet steam pressure exceeds the critical pressure. The critical pressure of water vapor is 22.1 MPa. Currently, supercritical pressure is mostly used in power plant boilers, ranging between 25–27 MPa.

Classified by the steam pressure generated by the boiler: low-pressure boilers (P≤2.5Mpa, T≤400℃)； Medium-pressure boilers (2.5Mpa＜P≤6Mpa, 400℃＜T≤450℃) ； High-pressure boilers (6Mpa＜P≤14Mpa, 460℃＜T≤540℃) ； Ultra-high pressure boilers (14Mpa＜P≤17Mpa, 540℃＜T≤570℃) ； Subcritical pressure boilers (P17–18 Mpa, 540℃ < T ≤ 570℃) ； Supercritical pressure boiler.

(1) Boilers with a low-pressure outlet steam pressure of 2.45 MPa or less generally have a steam temperature that is at saturation temperature or no higher than 400°C. (2) Boilers with an outlet steam pressure of 2.94–4.90 MPa for medium-pressure use. For the current parameter ranges of power station boilers in our country, the outlet steam pressure for medium-pressure boilers is specified at 3.83 MPa, with a steam temperature of 450°C. (3) Boilers whose steam outlet pressure at the high-pressure boiler stage is 7.84–10.8 MPa. For the current series of power station boilers in our country, high-pressure boilers have an outlet steam pressure of 9.81 MPa, with the outlet steam temperature typically being 540°C. (4) Ultra-high-pressure boilers have an outlet steam pressure ranging from 11.8 to 14.7 MPa. For the current parameter ranges of power station boilers in our country, the outlet steam pressure for ultra-high pressure boilers is specified at 13.7 MPa, with the steam outlet temperature being 540°C; in some cases it is 555°C. (5) Subcritical pressure boilers are those whose outlet steam pressure ranges from 15.7 to 19.6 MPa. For the current parameter series of power station boilers in our country, for subcritical pressure boilers, the specified outlet steam pressure is 16.7 MPa, with the outlet steam temperature being 540°C or 555°C; in a few cases it is 570°C. (6) Supercritical pressure boilers are those whose outlet steam pressure exceeds the critical pressure. The critical pressure of water vapor is 22.1 MPa. Currently, supercritical pressure is mostly used in power plant boilers, ranging between 25–27 MPa.

Low-pressure boilers, medium-pressure boilers, high-pressure boilers, ultra-high-pressure boilers, subcritical-pressure boilers, supercritical-pressure boilers

Based on the steam pressure generated by the boiler, boilers can be classified as follows: (1) Low-pressure boilers, whose outlet steam pressure is less than or equal to 2.45 MPa; the steam temperature in such boilers is usually at the saturation temperature or no higher than 400°C. (2) Boilers with an outlet steam pressure of 2.94–4.90 MPa for medium-pressure applications. For the current parameter ranges of power station boilers in our country, the outlet steam pressure for medium-pressure boilers is specified at 3.83 MPa, with a steam temperature of 450°C. (3) Boilers with a steam outlet pressure of 7.84–10.8 MPa in high-pressure boilers. For the current series of parameters for power station boilers in our country, high-pressure boilers have an outlet steam pressure of 9.81 MPa, with the outlet steam temperature typically being 540°C. (4) Ultra-high-pressure boilers have an outlet steam pressure ranging from 11.8 to 14.7 MPa. For the current parameter ranges of power station boilers in our country, the outlet steam pressure for ultra-high pressure boilers is specified at 13.7 MPa, with the steam outlet temperature being 540°C; in some cases it is 555°C. (5) Subcritical pressure boilers are those whose outlet steam pressure lies between 15.7 and 19.6 MPa. For the current parameter series of power station boilers in our country, for subcritical pressure boilers, the specified outlet steam pressure is 16.7 MPa, with an outlet steam temperature of 540°C or 555°C; in a few cases, it is 570°C. (6) Supercritical pressure boilers are those whose outlet steam pressure exceeds the critical pressure. The critical pressure of water vapor is 22.1 MPa. Currently, supercritical pressure is mostly used in power plant boilers, ranging between 25–27 MPa.

Low-pressure, medium-pressure, high-pressure, ultra-high-pressure, subcritical pressure, supercritical pressure boilers

I’m not too sure either; let’s see what others say

(1) Boilers with a low-pressure outlet steam pressure of 2.45 MPa or less generally have a steam temperature that is at the saturation temperature or no higher than 400°C. (2) Medium-pressure boilers with an outlet steam pressure of 2.94~4.90 MPa, and a steam temperature of 450°C. (3) For boilers with an outlet steam pressure of 7.84–10.8 MPa, the outlet steam temperature is usually 540°C. (4) Ultra-high pressure boilers: Boilers with an outlet steam pressure of 11.8–14.7 MPa, with a steam outlet temperature of 540°C; in some cases, it is 555°C. (5) Subcritical pressure boilers: Boilers with an outlet steam pressure of 15.7–19.6 MPa, with an outlet steam temperature of 540°C or 555°C; in some cases, it is 570°C. (6) Supercritical pressure boilers: Boilers whose outlet steam pressure exceeds the critical pressure. The critical pressure of water vapor is 22.1 MPa.

Low-pressure boilers, medium-pressure boilers, sub-high-pressure boilers, high-pressure boilers, sub-critical boilers, super-critical boilers.