Working Principle
Compressed natural gas (CNG) enters the primary heat exchanger through the filter, ball valve, and emergency shut - off valve. Inside the primary heat exchanger, the gas is heated. After heating, the gas is regulated in pressure by the primary pressure regulator and then enters the secondary heat exchanger and the secondary pressure regulator. After secondary pressure regulation and heat exchange (if a lower outlet pressure is required, a third - stage pressure reduction is needed), the gas enters the flow meter for measurement. Finally, it passes through the odorizer and exits the station. The pressures, temperatures at all levels within the pressure - regulating equipment, as well as the emergency shut - off, are displayed and interlocked through the central control system.
Technical Features
- Classified as single - stage, two - stage, three - stage, or multi - stage pressure regulation according to the number of pressure - regulating times.
- All pressure - regulating pipelines are divided into two paths, with one in use, one in standby, and one as a bypass, ensuring uninterrupted gas supply to the downstream.
- The pressure - regulating device is equipped with a high - precision filter with a filtration accuracy of 5μm. It is simple to operate, safe, efficient, and convenient for maintenance.
- The pressure regulators are imported products.
- The pressure - regulating station is equipped with primary and secondary heat exchangers to ensure the normal operation of the equipment in severe winter.
- The pressure - regulating station is equipped with an ultra - high - pressure automatic shut - off device and a safety relief device. When fluctuations occur in gas consumption and inlet pressure, the outlet pressure can be automatically maintained within a certain range.
- The pressure - regulating device has functions such as multi - point interlock control, flow measurement, remote transmission and display, automatic odorization, and automatic alarm.
Working Principle
A long - distance gas pipeline system typically consists of gathering and transportation pipe networks, gas purification equipment, main gas transmission pipelines, compressor stations, block valve chambers, distribution valve chambers, distribution stations (terminal pressure - regulating and metering stations), management and maintenance stations, communication and remote - control equipment, cathodic protection stations (or other electrical protection devices), and pipeline accessories.
The gas collected from the gas source contains a large amount of impurities and harmful substances, and its pressure fluctuates significantly. Before gathering and transportation, it needs to go through throttling to separate free water, oil, and mechanical impurities, etc., and then enters the gas gathering station through the gathering pipeline. The gas leaving the gas gathering station enters the treatment plant (for desulfurization, etc.) for further purification, and then enters the first - stage gas transmission and distribution station. At the starting station, the gas is dust - removed, pressure - regulated, and metered before being sent into the main gas transmission pipeline.
Technical Features
- The station equipment is integrated and skid - mounted, which is convenient for installation and station - building, and can receive and transport natural gas to downstream stations.
- To ensure production safety, high - and low - pressure alarm devices are usually installed at the station entrance. When the gas from the upstream is over - pressured or a pipeline accident occurs, the incoming natural gas should be cut off urgently.
- The station transports purified natural gas that has been separated and metered within the station. Usually, a low - pressure alarm device is installed at the station exit. When a downstream pipeline accident occurs, the outgoing natural gas should be cut off urgently.
- The pressure - regulating device has functions such as multi - point interlock control, flow measurement, remote transmission and display, and automatic alarm.
