Process Documentation

Process documentation is a key early-stage process-engineering function that is essential to a quality project outcome. P&ID and PFD provide the design basis on which the rest of the project relies. Other documentation is often created from these two most basic documents.

The information in these documents is used for many purposes, including but not limited to:

Client/engineer agreement on project scope
Initial cost estimation
Gap analysis, infrastructure requirements
Process-hazard assessment
Equipment specifications
Instrument specifications
Piping specifications, including sizing
Development of control strategy and the functional specification

For more information on key process documents, click on the links below.

Process flow diagrams (PFD) describe a manufacturing process in terms of the various steps involved and the inputs and outputs from those steps. This is often the initial document generated in a new process, as it gathers the data known, sets the process operating conditions, and allows the sizing of equipment. The PFD usually refers to a mass and energy balance, which is often incorporated right into the diagram in the form of a table.

Typical information on a PFD includes:

Blocks for each unit operation
Lines indicating the flow of materials (process streams)
Lines indicating the flow of energy
Unique identification of each steam and energy input or output

When the mass and energy balance is included on the PFD, it will include information such as:

Materials, chemicals, and utilities such as steam, hot oil, air, etc.
Total flows, flows per unit time or other rate information
Physical properties of materials if necessary
Conditions such as temperature, pressure, quality, etc.
Other information that may be helpful for those preparing the P&ID or equipment or piping specifications

Also see Piping and Instrumentation Diagrams (P&ID)

Process Flow Diagrams (PFD)

CEI engineers understand the benefits of effective equipment layouts to minimize cost and space requirements while maximizing operations efficiency.

They all have extensive plant experience. Logical process flow, operator access, constructability, maintenance access, housekeeping, future expansion, and other factors need to be considered in laying out equipment. It is essential that the process be a collaborative effort between client and the engineering firm. CEI’s experienced engineers are available to assist in developing an effective equipment layout for your process.

Equipment Layouts

The engineers at Creative Engineers Inc., are very experienced at piping design and providing specifications and detailed drawings for piping systems. Our engineers’ experience covers a wide range of applications and design conditions:

High pressure
Deep vacuum
High temperature
Hazardous materials
Corrosives
Cryogenics
Special pipe materials

Effective system piping design requires consideration of future requirements to prevent the evolution of a pipe system that makes new piping difficult to install and more costly than necessary.

Piping Design

For projects that are complex or require generation of significant specifications, piping models or other documentation, this package is a powerful cost saver. The intelligent P&IDs are integrated into all equipment and piping specs, allowing automatic report generation and material spreadsheets.

For projects requiring 3D piping models, the P&IDs feed directly into the models meaning the model generation time is greatly reduced. Call CEI today and see if this tool makes sense for your project.

See our example of a loop diagram (PDF).

P&ID - Piping and instrumentation diagrams (PID) describe the process flow for chemical processes. A great deal of information can be represented in a “simple” diagram. Information about the piping is represented, including pipe size, pipe material of construction, insulation, and pipe specification. Location of valves, pumps, check valves, filters, strainers, and hoses are simply displayed for an easy-to-understand and -identify arrangement.

P&ID – Piping and Instrument Diagrams (PID)

Instrumentation is displayed using standardized symbols and labeling representing the process-sensing and -control elements. Instrumentation includes:

Temperature Elements (T/Cs, RTD, Thermister)
Flow Meters and Flow Transmitters
Pressure Gages and Pressure Transmitters
Level Gages and Level Transmitters
Analyzers (pH, gas, LEL, etc.)
Weight Instruments (scales, load cells)

Instrumentation also includes process-control devices such as actuated valves, control valves, pressure regulators, pressure-relief devices, and conservation vents.

Process control can also be represented on the P&ID to simply display how the process operates. For example, a flow meter may be used to control a valve to provide a constant flow rate to a process. Interlocks can be displayed and documented on the drawing. On a single drawing the interlocks represent what triggers an automatic response and what actions are taken.

Equipment represented on the P&ID include tanks, pumps, mixers, agitators, centrifuges, totes, drums, heat exchangers, condensers, conveyors, and filters.

Creative Engineers, Inc., has years of experience with the industry-accepted ISA standard for instrumentation drawings. We engineer the process before building, saving time and money for our customers. We have an in-depth understanding of the process and how to control it. We engineer-in safety and simplify maintenance where possible. Good designs allow for good estimates and accurate scheduling of new or expanded processes.