Causes of steam generator pressure changes

The operation of the steam generator requires a certain pressure. If the steam generator fails, changes may occur during operation. When such an accident occurs, what is the general cause? What do we need to do? Today, let’s learn more about it with Nobeth.

If the steam pressure changes during operation, it must first be determined whether the cause is internal resistance or external disturbance, and only then can Bodang be adjusted.Changes in steam pressure are always closely related to steam meteors, so the relationship between steam pressure and steam flow can be.

To determine whether the cause of the change in steam pressure is internal disturbance or external disturbance.

External interference: When the steam pressure decreases, the steam flow meter indication increases, indicating that the external demand for steam increases; while the steam pressure increases, the steam flow decreases, indicating that the external steam demand decreases. These are all It is an external disturbance. That is to say, when the steam pressure changes in the opposite direction to the steam flow rate, the cause of the steam pressure change is external disturbance.

Internal disturbance: When the steam pressure decreases, the steam flow rate also decreases, indicating that the fuel in the furnace is insufficient for heat supply, resulting in a decrease in evaporation; while the steam pressure increases, the steam flow rate also increases, indicating that the evaporation volume in the furnace decreases. Combustion heat supply is too high to increase evaporation, which is an internal disturbance. That is, when the steam pressure changes in the same direction as the steam flow rate, the cause of the change in steam pressure is internal disturbance.

It should be pointed out that for the unit unit, the above method of judging internal disturbance is only applicable to the initial stage of the change of working conditions, that is, it is only applicable before the turbine speed regulating valve is activated. After the speed regulating valve is activated, the boiler steam pressure and steam The direction of flow change is opposite, so attention should be paid during operation.

The reason for the above special situation is: when the external load remains unchanged and the boiler combustion star suddenly increases (internal disturbance), initially when the steam pressure rises, the steam flow also increases. In order to maintain the rated speed of the steam turbine, the speed regulating steam valve will be closed. Small, then the steam pressure will continue to rise while the steam flow rate decreases, that is, the steam pressure and flow rate change in the opposite direction.

In reality, there are many more factors that change pressure. However, it should be noted that the pressure control is an adjustment with relatively large inertia and lag. Once the force is exerted, the consequences will be very serious. Therefore, if you have any questions during use, you must consult the manufacturer as soon as possible. We will wholeheartedly Answer all kinds of questions about steam generators for you.