Operating maps and diagrams (operating diagrams) provide a high-level schematic configuration of natural gas transmission and distribution systems, individual stations and certain operating parameters. They are useful in identifying the key components that determine how a system or station functions and operates.

A comprehensive and accurate operating diagram is a valuable tool used by engineering and operations personnel to facilitate an understanding of the flow and operation of a gas system or individual station. Accurate operating diagrams support improved decision making by engineering and operations staff for safe operation and maintenance, project planning, project design and project execution. In order to have full system knowledge, it is critical to create and continually maintain operating diagrams for gas systems and stations. 

At a high level, an operating diagram shows the physical interconnection of gas piping, equipment, features, and parameters including, open and closed valves, regulators, meters, relief valves, sensing line taps, MAOP break lines, pipe diameter, and gas flow direction.  An operating diagram also shows key identifying information such as, regulator run numbering and valve numbers that correlate to equipment tags in the field. In addition, the normal position of valves (open or closed) are depicted on operating diagrams.  It is also beneficial to depict relative locations of sensing line taps and pressure taps on operating diagrams.

To be set up for success, it is important to create an operating diagram standard that includes a symbology document to create consistency across all gas systems and stations. This symbology is recommended to be attached to all operating diagrams.

Another critical component of the operating diagram standard is a review, update and maintenance process. In order to ensure all parties can view and use the most current diagram, each operating diagram is recommended to be field verified on a routine basis. This field verification will include updating and verifying the locations of sensing taps, operation of control valves and bypass valves, reconciliation of valve numbering and tagging to ensure accuracy and safety.

GTS has extensive experience assisting operators by creating hundreds of operating diagrams for simple to complex gas systems and stations, including regulator facilities, metering stations, and mainline valve sets. GTS’s experience also includes the creation of operating diagram templates, symbology, and standards.

Please contact Joe Medina (joemedina@gtsinc.us) for additional information.