Generally, the boiler outlet water vapor pressure is less than 1.9 MPa, which is called a low-pressure boiler;
一般将2吨蒸汽锅炉出口水蒸气压力为1.9兆帕以下的锅炉，称为低压锅炉;
Boiler outlet water vapor pressure of about 3.9 MPa boiler, known as medium pressure boiler;
锅炉出口水蒸气压力为3.9兆帕左右的锅炉，称为中压锅炉;
Boiler outlet water vapor pressure of about 9.8 MPa boiler, known as high-pressure boiler; boiler outlet water vapor pressure of about 13.97 MPa boiler, referred to as ultra-high pressure boiler;
锅炉出口水蒸气压力为9.8兆帕左右的锅炉，称为高压锅炉;锅炉出口水蒸气压力为13.97兆帕左右的锅炉，称为超高压锅炉;
Boiler outlet water vapor pressure of about 17.3 MPa boiler, known as sub critical pressure boiler;
锅炉出口水蒸气压力为17.3兆帕左右的锅炉，称为亚临界压力锅炉;
Boiler outlet water vapor pressure of about 17.3 MPa boiler, known as sub critical pressure boiler;
Boiler whose outlet water vapor pressure is above 22.12 MPa is called supercritical pressure boiler.
锅炉出口水蒸气压力在22.12兆帕以上的锅炉，称为超临界压力锅炉。
