Regular readers of the SSP Innovations Energy Advisor e-zine know that we have put out a lot of quality content around Esri’s new ArcGIS Utility Network Management Extension technology for electric utilities. For those of you who are new to this blog, and are interested in these earlier posts, you can reference previous content here. In this article, we’ll focus on utility network management for gas.
More recently, SSP has had a chance to work with a pre-release version of the ArcGIS Utility Network Management Extension for natural gas and hazardous liquids networks. I’m excited about the future capabilities the software will offer for utilities and pipeline operators. For utilities and pipeline operators, the Utility and Pipeline Data Model (UPDM) is the geodatabase data model template of choice for those looking to work with the ArcGIS Utility Network Management Extension for gas.
Background: The Utility and Pipeline Data Model
Esri has collaborated with leaders in industry and academics to create a practical and up-to-date data model template, the Utility and Pipeline Data Model (UPDM). UPDM is catered to the needs of pipe network operators in the gas and hazardous liquids industries. This data model allows Esri customers to model each physical component of a gas or hazardous liquids pipe network in a single geodatabase. For instance, a user may model from the wellhead to the customer meter or from a wellhead to a terminal or delivery point. Implementing the UPDM data model allows users of the ArcGIS platform to install, configure and deploy Esri technology related to gas and hazardous liquids networks in a more efficient and effective manner, while supporting industry specific best practices. The UPDM data model will also be the foundation for the gas and hazardous liquids specific functionality being introduced in the ArcGIS Utility Network Management Extension for gas.
The Same Concepts, but a Different Commodity: Utility Network Management for Gas
Readers familiar with the utility network concepts from our electric-focused posts will see many similarities with the ArcGIS Utility Network Management Extension for gas, along with some key differences. One similarity is that gas networks will be modeled with a set of five feature classes similar to those that were introduced with the electric model. The key difference is that these feature classes will contain gas specific subtypes and attribution.
The five feature classes in the UPDM data model which will support the ArcGIS Utility Network Management Extension for gas will include:
- UPDMAssembly – The assemblies and stations of a pipe system. Examples of items modeled in this feature class include Compressor Stations, Regulator Stations and Meter Settings.
- UPDMLine – All pipes in which the commodity flows. Examples of items modeled in this feature class include Pipes, Service Lines, and Station Pipe.
- UPDMDevice – The components within the pipe system that can interact with the commodity through impedence, filtration, and measurement. Examples of items modeled in this feature class include Wellhead Source Flanges, Valves, Controllable Tees, and Rectifiers.
- UPDMJunction – The components of the pipe system which do not have the ability to impede, filter, or measure the flow of the liquid or gas moving through the pipe system. Examples of items modeled in this feature class include Transitions, Elbows, and Couplings.
- UPDMSubnetLine – The line feature class updated with the geometries of the subnetworks as they are created in the Utility Network.
As with the electric utility network model, the combination of the AssetGroup and AssetType attributes will identify the type of asset being represented in the feature classes above. For example, a Critical Valve would be represented in the UPDMDevice feature class with an AssetGroup value of “Valve” and an AssetType value of “Critical.”
Your gas and hazardous materials network will exist as a different domain network within your geodatabase providing the capability to model multiple commodity networks within one utility network.
Tiers and Subnetworks
Just as in electric where users can model the Generation, Transmission, and Distribution tiers of the electric network, the UPDM model and the ArcGIS Utility Network Management Extension for gas allows for the modeling of three distinct tiers within a gas or hazardous liquids network:
- The System Tier
- The Pressure Tier
- The Isolation Tier
In the System tier, users will have systems that are identified to denote individual sections of that tier. These sections will be modeled as subnetworks, and will include subnetwork conntrollers which will be used to properly define their extent. An example of this concept would a “West Gathering Field” system that represents a subset of gathering related components for a geographic area of the System tier.
Given that the pre-release version that we’ve worked with requires you to adhere to a strict hierarchy of creating systems, then pressure zones, and then finally isolation zones, once your systems are created you will want to create the pressure zones for your network.
Pressure zones allow users to identify and manage areas of the gas pipe network that are pressurized at the same level. These areas are modeled as subnetworks, and are created by identifying the subnetwork controllers that will act as the sources of a given pressure zone.
In the configuration of our pre-release version, six devices are denoted as valid subnetwork controllers for the Pressure tier:
- Compressor\Electric Motor
- Compressor\Reciprocating Engine
- Valve\Pressure Reducing
- Temp Source Location\Regulator Station
Identifying subnetwork controllers on terminals of these devices allows the software to trace out a pressure subnetwork and then store them in the network model.
Once pressure zones have been established, users are then able to build isolation zones within the pressure zones that have been defined. This process is very similar to the creation of other subnetworks, where the user will define the terminal on the subnetwork controller feature that will define a source of the isolation zone.
Savvy readers will quickly see that the modeling of the various systems and zones is heavily dependent on the software’s ability to create and manage meshed subnetworks. Take, for example, “Isolation Zone 2” in the diagram above. To create this isolation zone, a terminal on five different critical valves (configured as valid subnetwork controllers for the Isolation tier) were identified as subnetwork controllers for this isolation zone subnetwork. Looking at the SubnetworkLine feature class showcases this capability in even greater detail.
Supporting Customer Needs
The capabilities discsussed in this post represent important gas and pipeline network requirements that Esri customers have been asking for. As background, Esri has collected user requests and business value points around network visualization, maximum allowable operating pressure (MAOP), pressure zones, and other key areas. Esri then incorporated these user requests and market problems into the functionality available in the ArcGIS Utility Network Management Extension for gas. Some examples of industry challenges made simpler with the new network management capabilities include:
- Network performance and visualization – With the implementation of the SubnetworkLine feature class, systems, pressure zones, isolations zones, and soon cathodic protection (CP) zones will be represented as a single line feature in the geodatabase. This will provide quicker map draw times because only one call is being made to the database per zone, rather than having to access and draw each pipe segment, valve, etc., that participate in the zone. This will also improve the user experience for visualizing these subnetworks by improving symbolization and web mapping options.
- CP zone rectifier sizing – Subnetworks allow the user to summarize important attribute values for the extent of the subnetwork, and this can be very useful in many business scenarios. Take, for example, the sizing of a rectifier to feed a cathodic protection zone. The sizing of the rectifier (in amps) for a CP zone is determined by the surface area of the metallic pipe that needs to be protected. With subnetwork attribute summarization, users can quickly get an understanding of the total distance of pipe by diameter within a subnetwork, which provides a critical component of data to feed a rectifier sizing calculation.
- Determining the MAOP of a pressure zone – With subnetwork attribute summarization, users can configure pressure zone subnetworks to track the minimum MAOP value of all components within that subnetwork. This allows for a streamlined way to determine the true pressure a zone can be operated at, and helps identify any critical differences in allowable versus currently operated pressure.
- Pressure changes based on load forecasts – During times of known gas demand increases, network operators will add in additional gas (a process referred to as “packing the line”) prior to these high demand periods, with the understanding that the increased demand will normalize the pressure of the line. Using the subnetwork capabilities the framework provides, users will be able to easily determine the volume of a subnetwork and how much gas needs to be added to an existing zone to prepare for these times of increased demand.
Esri will continue its work around gathering customer requirements and needs related to network management for gas and pipeline operators to ensure that their latest technology matches the needs of its users both now and in the future. Customers can expect continued enhancements to the framework as development continues.
More to Come for Utility Network Management for Gas
While there are many exciting capabilities available in the pre-release version of the utility network management for gas and hazardous liquids networks, there is even more to come as we look towards the future. Support for cathodic protection, more advanced isolation tracing (including squeeze-offs and temporary sources), pipe integrity, inspections, and other capabilities will be introduced to evolve how gas and hazardous liquids networks are supported using the ArcGIS platform. You can rest assured that SSP will be right there at the leading edge, providing valuable content utilities and pipeline operators can use to stay up to date with the latest Esri technology.