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НаименованиеA Gas-Flow Regulator

 

This article describes a gas flow regulator with an aperture of from 300 to 1,200 mm and a built in control system.

Any valve having a two-way pneumatic or hydraulic servo and a BUEP-160/8-type control unit can be used for this device. The primary control functions are performed using a power unit and a control unit. Natural gas energy is used to turn the valve, and oil with a low solidification point is used as the working agent. The power unit, which uses two batteries, converts natural gas energy into hydraulic power and also prevents the valve from turning on its own.

The power unit is controlled by a microprocessor that monitors for changes in gas pressure and, based on a special algorithm, adjusts the valve to obtain the desired pressure.

The control unit can work on its own or can be operated remotely by a technician. The unit can operate in active mode, independent of a master computer, or in passive mode, fulfilling commands from the computer.

ISO 9001-certified MicroPC components from Octagon Systems were selected for the control unit because of their high reliability. All the components use low levels of power and so do not require forced cooling. The MicroPC components allow the device to be used in temperatures from -45 to +60 degrees C, with a relative humidity of up to 98% at 35 degrees C.

The device's construction, using an explosion-proof shell, allows it to be used in areas where there is the risk of explosions. Exposed connectors for special controllers and other areas not protected from explosion can be made using nonsparking circuits.

The control unit is IBM PC-compatible and boots automatically with an MS-DOS-compatible system upon turning on. Applications can be written on a PC and uploaded into the device remotely. After the upload, the unit automatically reboots.

The system controls the flow based on the discharge rate as measured by the Superflo device widely used in the gas industry. Data from the device is relayed through an automated workstation (AWS) into the controller and is used to control the flow. The Superflo is connected to the PC using an RS-232 interface.

For remote operations, the controller is equipped with a modem and transmits data via telephone.

The software loads automatically upon booting. It queries the valve controllers, controls the valve based on its assigned algorithm, exchanges information with the AWS and gas flow rate calculators, stores historical data and maintains an event log.

The AWS software runs under DOS and includes a communications module; a set of programs that connect the user with various devices; and a set of service applications.

The illustration shows a screenshot of the display and the regulator control process.

To date the automated gas flow control equipment has gone through field testing and is being prepared for installation at Yugtransgaz's Yelshanskoye underground gas storage facility.

 

 

A screenshot of the display and the regulator control process.

Efim Kats,  Sergey Levanov