Extraction steam turbine mechanical working principle is about the first pressure, operation to that mode, which extraction steam pressure according to the needs of users and product series requirements and determine, can be adjusted in a certain range, according to the different number of extraction steam, extraction steam turbine is divided into single extraction and double extraction two. Single exhaust steam flow can be divided into high pressure and low pressure two sections. The flow through part of double exhaust steam is divided into high pressure, medium pressure and low pressure three sections. Each section is provided with a separate cylinder, forming a separate cylinder arrangement, or several sections together in a cylinder, forming a single cylinder arrangement. There is a steam outlet between the sections, part of the steam out of the mouth, the rest of the flow into the next section through an adjustable mechanism. The commonly used flow regulating mechanism has a regulating valve and can change the annular flow area of the rotary baffle two kinds.
In addition, the operation mode is that the extraction steam turbine needs both power supply and heat supply when it runs. When the extraction steam volume is zero, it is the same as the condensing steam turbine. The steam entering the steam turbine flows into the boiler feed water heater except for part of the steam, and the rest of the steam flows through all levels and enters the condenser. When the extraction volume is not zero, the steam entering the turbine first through the high pressure section for work at all levels, and then part of the steam through the extraction port for heating; Another part of the steam through the regulator or rotating partition through the rest of the stage, continue to work, and finally into the condenser. At this time, if the electrical load drops, the turbine speed rises, the governor action, high pressure regulating valve and pumping regulating valve (or rotating partition) are turned down, so that the power drops, keep pumping volume unchanged.
