An Overview of the Piping and Instrumentation Diagram

Piping and Instrumentation plays a key role in the overall operation of the oil and gas industry. It is responsible for the safe and efficient transportation of the fluids from one end of the process column to the other. An important representation of the piping and instrumentation used in a process is through the pipeline and instrumentation diagram (P&ID). A P&ID demonstrates all piping, including the physical series of branches, reducers, instrumentation, expanders, valves, equipment, and control interlocks. It is widely used to understand and operate the process system. A lot of modifications, revamp, and debottlenecking are identified and carried out with the help of P&IDs.

In this article, let us take an overview of the piping and instrumentation diagrams, types of piping equipment and intelligent P&IDs.

Importance of P&IDs for Piping Equipment Companies

The importance of P&IDs cannot be stressed enough. P&IDs are strategic documents providing the blueprint for every process associated with the piping and instrumentation and the operation on a whole. Hence every P&ID is kept updated throughout the life span of the project. Any modification across the project has to be demonstrated in the P&ID. Keeping P&IDs up-to-date with the latest changes ensures personnel safety and enables them to understand the operation underway in the plant.

P&IDs for the piping and instrumentation at the facility are created during the design phase of a project, most likely in the Front End 2 phase, which is then simulated using the software in order to test its feasibility. The generation of P&IDs improves the accuracy of the cost estimation multifold. This becomes possible because reasonably accurate estimates of equipment and material can be developed.

Introduction of Intelligent P&IDs

P&IDs are often made using Computer-aided Design (CAD) software. However, the traditional P&ID generation method has been slowly replaced by Intelligent P&IDs to depict the piping and instrumentation present at the facility. An Intelligent P&ID integrates a CAD drawing along with a database that is curated and maintained simultaneously. The real-time link between the entities displayed on the drawing and specific data stored in the database brings about the required intelligence. This eliminates the presence of data at two locations as the conventional P&ID’s are generated manually by entering the information present in the P&ID into a spreadsheet. Let us understand how Intelligent P&IDs are benefitting the engineers who involved in piping and instrumentation:

1) Within the Intelligent P&ID ecosystem, data entries, corresponding to the piping and instrumentation equipment, made to either the drawing or the database are maintained in a single database and are kept updated in both platforms. One of the foremost advantages of this system is that whatsoever lists and reports cited earlier can be produced anytime after the drawings begin.

2) Intelligent P&ID’s have more information on the piping and instrumentation of process than their traditional precursors. For instance, when a pump is incorporated into an intelligent P&ID, the software requires the input to the inlet and discharge sizes so that the background database can trace the piping into and out of the pump. The same goes for most inline equipment and devices.

3) One of the common problems faced in a processing facility is the lack of knowledge about the impeller size of each deployed centrifugal pump. Most facilities don’t want to take the pain in updating each traditional P&ID when such change takes place. When smart P&IDs are used for demonstrating the piping and instrumentation of a facility, the maintenance personnel can easily revise the data record for a particular pump, and the P&ID will be get up to date.

Piping Equipment List in P&ID

Piping equipment are a set of devices and systems in place to transport fluids around the facility, all the while ensuring less energy consumption. They are the most essential part of the piping and instrumentation of any facility. Some of the most important piping equipment have been listed here:

• Pipes: The pipes used in the oil and gas industry mostly fall in three categories: Seamless Steel Pipe, Electric Resistance Welding (ERW) pipes, and Longitudinal Submerged Arc Welding Pipe (LSAW). The seamless pipes are manufactured beginning from steel billets, which are heated and perforated to create a tubular section. “Seamless” implies the absence of seam welds. ERW Pipes, on the other hand, are fabricated using steel coils, with the coil being uncoiled first, then smoothened, cut and, eventually formed into a pipe section by connecting its two extremities electrically. LSAW pipe is fabricated using JCOE process wherein steel plates undergo cutting, bending and welding. LSAW pipes are the most preferred choice for pipelines above 24 inches.

  

• Flanges: Flanges are an essential part of the piping and instrumentation family, and are used for connecting pipes, valves, pumps and other equipment. Flanges allow easy access of equipment for cleaning, inspection or modification. Pipe flanges are manufactured by stainless steel, cast iron, aluminum, brass, bronze, plastic etc. The most common type of flanges found in the oil and gas industry are the Adaptor Flange, Open Face Flange, RTJ Flanges, Spacer Flanges, Studded Face Flanges, Threaded Flanges, Weld Neck Flanges, and Segmented Flanges.

  

• Valves: Valves are essential pieces of piping and instrumentation and are used to control the flow and pressure within a system or process. They convey liquids, gases, vapors, slurries etc around the facility. Different types of valves are available: gate, globe, plunger, butterfly, check, diaphragm, pinch, gas pressure regulator, pressure relief, control valves etc. Each valve type comes with numerous models, different features and functions. While some of the valves are self-operated, others are controlled manually or with an actuator or pneumatically or hydraulically.
• Fittings: Fittings are used in the oil and gas industry for various purposes like connecting the straight pipe or tubing sections, adapting to different sizes or shapes and regulating or measuring fluid flow, and are important pieces of piping and instrumentation. They form the peripheral of pipes and majorly assist in the regulation and measurement of fluid flow.

  

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