Serving the Oil & Gas Industry Since 1980

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gas blowdown system

Pipeline Gas Blowdown Systems

Operators of natural gas pipeline systems routinely reduce line pressure and discharge gas from pipeline sections to ensure safe working conditions during maintenance and repair activities.

A Pipeline Gas Blowdown System is used to quickly and safely remove gas from a blocked-in pipeline section. The Blowdown system allows an operator to quickly remove the gas from a large section of pipeline for repair or maintenance. The Blowdown system removes the moisture from the gas and reduces the blowdown noise to 85 dB A at 100 feet. A control valve on the inlet reduces the pressure of gas flow through the high efficiency separators, and a silencer reduces the exit noise level.


EN-FAB, Inc. has developed a modularized trailer unit for pipeline gas blowdown. The design provides for:


  • Reduction of all possible pressures


  • Measurement of gas flow rate


  • Separation of gas, liquids, and solids


  • Reduction of operating noise to a permissible level


  • Removal of distasteful gas odorants utilizing a deodorizing medium


These trailers are designed for movement along difficult terrain and can be camouflaged to blend into the surroundings. Trailer design meets local transportation requirements.


Main Components


  • Two (2) High efficiency separators


  • Two (2) Pressure / Flow Control Valves


  • Two (2) 8” RF Orifice Plate Holders


  • One (1) Vent Natural Gas Blowdown Silencer


  • Two (2) Pressure Indicating Controllers


  • Two (2) Differential Pressure Indicating Controllers


  • CO2 Fire Extinguisher System


  • Two (2) Nitrogen Supply Assemblies


The system is designed for portability along the pipeline to selected sites for cleanup, blowdown, and maintenance requirements.


Portable Gas Blowdown System

Typical Process Conditions


Gas Flow Rate

Gas Specific Gravity

Inlet Gas Temperature

Inlet Gas Pressure

Outlet Gas Pressure

Liquid Water Rate

Liquid Hydrocarbon Rate

Overall Noise Level

Blowdown Separators Efficiency




.60 to .65

.60 to .65

 65 deg F

1200 psig to Atmos.


0 Gal/Day

1.0 Gal/Min (Max)

Not to exceed 85 dba @ 100 feet

Remove 98% of all the entrained liquid particles 6 microns and larger at design flow rate.


enfab inc logo
gas blowdown system
enfab inc logo
gas blowdown system
Portable Gas Blowdown System
gas blowdown system
Portable Gas Blowdown System

Contact Info

EN-FAB, Inc.

3905 Jensen Drive

Houston, Texas 77026

Mon - Fri 08:00 - 17:00