Boiler Automatic Water Supply System

Overview

The Boiler Automatic Water Supply System is designed to automatically regulate and control the feedwater flow to the boiler, ensuring its normal operation and maintaining a stable steam drum water level. This system is crucial for the safe operation of the boiler, as excessive or insufficient water levels can lead to boiler accidents.

System Composition

The Boiler Automatic Water Supply System typically consists of feedwater pumps, feedwater piping, control valves, water level measurement devices, and controllers. The feedwater pumps provide sufficient pressure to ensure water can smoothly enter the boiler. The feedwater piping transports the water into the boiler. The control valves regulate the flow of feedwater. The water level measurement devices monitor the steam drum water level in real-time. The controller adjusts the valve opening based on signals from the water level measurement devices to regulate the feedwater flow.

Working Principle

The working principle of the Boiler Automatic Water Supply System is based on feedback control. When changes occur in the steam drum water level, the water level measurement devices detect these changes and transmit signals to the controller. The controller calculates the required feedwater flow based on the preset water level range and the current water level, and adjusts the valve opening to achieve this target. If the water level is too high, the controller reduces the valve opening to decrease the feedwater flow; if the water level is too low, the controller increases the valve opening to increase the feedwater flow.

System Types

There are various types of Boiler Automatic Water Supply Systems, including single-stage three-impulse feedwater regulation systems, cascade three-impulse feedwater regulation systems, and feedwater regulation systems using variable-speed pumps. These systems have their own characteristics and are suitable for different boiler types and operating conditions.

1. Single-Stage Three-Impulse Feedwater Regulation System: This system uses the steam drum water level as the primary regulation signal, while introducing feedwater flow and steam flow as feedforward signals. It regulates the feedwater flow to maintain a stable steam drum water level.

2. Cascade Three-Impulse Feedwater Regulation System: Based on the single-stage three-impulse system, this system adds a secondary regulator for finer adjustment of the feedwater flow, further enhancing the stability of the steam drum water level.

3. Feedwater Regulation System Using Variable-Speed Pumps: This system adjusts the feedwater flow by changing the speed of the feedwater pumps. The variable-speed pumps can adjust their speed according to the actual demand of the boiler, achieving more precise feedwater control.

Advantages

The Boiler Automatic Water Supply System offers multiple advantages, including improved safety, stability, and economy of boiler operation. By automatically regulating the feedwater flow, the system ensures a stable steam drum water level under various operating conditions, preventing boiler accidents caused by excessive or insufficient water levels. Additionally, the system adjusts the feedwater flow based on the actual demand of the boiler, contributing to energy savings and cost reduction.

Maintenance and Servicing

To ensure the normal operation and long-term stability of the Boiler Automatic Water Supply System, regular maintenance and servicing are required. This includes checking the accuracy and sensitivity of the water level measurement devices, cleaning the control valves and piping, inspecting the operating status of the feedwater pumps, and periodically performing performance tests and calibrations to ensure that the system's performance indicators meet design requirements.

In summary, the Boiler Automatic Water Supply System is a critical safeguard for the safe operation of boilers. By automatically regulating and controlling the feedwater flow, the system ensures a stable steam drum water level and good operating status of the boiler under various conditions.