Piping and instrumentation diagram - AbsoluteAstronomy.com

A piping and instrumentation diagram/drawing (P&ID) is a diagram in the process industry which shows the piping of the process flow together with the installed equipment and instrumentation.

Contents and Function

A piping and instrumentation diagram/drawing (P&ID) is defined by the Institute of Instrumentation and Control as follows:

A diagram which shows the interconnection of process equipment and the instrumentation used to control the process. In the process industry, a standard set of symbols is used to prepare drawings of processes. The instrument symbols used in these drawings are generally based on International Society of Automation (ISA) Standard S5. 1.
The primary schematic drawing used for laying out a process control
Process control
Process control is a statistics and engineering discipline that deals with architectures, mechanisms and algorithms for maintaining the output of a specific process within a desired range...

installation.

P&IDs play a significant role in the maintenance and modification of the process that it describes. It is critical to demonstrate the physical sequence of equipment and systems, as well as how these systems connect. During the design stage, the diagram also provides the basis for the development of system control schemes, allowing for further safety and operational investigations, such as the hazard and operability study (HAZOP).

For processing facilities, it is a pictorial representation of

Key piping and instrument details
Control and shutdown schemes
Safety and regulatory requirement
Regulatory requirement
Regulatory requirements are part of the process of drug discovery and drug development. Regulatory requirements describe what is necessary for a new drug to be approved for marketing in any particular country. In the US, it is the function of the Food and Drug Administration to establish these...

s
Basic start up and operational information

List of P&ID items

Instrumentation and designations
Mechanical equipment with names and numbers
All valves and their identifications
Process piping, sizes and identification
Miscellanea - vents, drains, special fittings, sampling lines, reducers, increasers and swagers

Permanent start-up and flush lines
Flow directions
Interconnections references
Control inputs and outputs, interlocks
Interfaces for class changes
Computer control system input
Identification of components and subsystems delivered by others

Identification and Reference Designation

The P&ID is used for the identification of measurements within the process. Identification letters for measurements are based on Standard S5. 1 and ISO 14617-6:

First-Letter	Measurement
A	Analysis
B	Burner, Combustion
C	User's Choice (usually Conductivity)
D	User's Choice (usually Density)
E	Voltage
F	Flow
G	User's Choice
H	Hand
I	Current
J	Power
K	Time, Time Schedule
L	Level
M	User's Choice
N	User's Choice (usually Torque)
O	User's Choice
P	Pressure
Q	Quantity
R	Radiation
S	Speed, Frequency
T	Temperature
U	User's Choice (usually Alarm Output)
V	Vibration, Mechanical Analysis
W	Weight, Force
X	User's Choice (usually on-off valve as XV)
Y	Event, State, Presence
Z	Position, Dimension

For reference designation of any equipment in industrial systems the standard IEC 61346

IEC 61346

IEC 61346 is an electrotechnical standard entitled "Industrial systems, Installations and Equipment and Industrial Products — Structuring Principles and Reference Designations"...

(Industrial systems, installations and equipment and industrial products — Structuring principles and reference designations) can be applied. For the function Measurement the reference designator B is used, followed by the above listed letter for the measured variable.

For reference designation of any equipment in a power station the KKS Power Plant Classification System can be applied.

Symbols of chemical apparatus and equipments

Below are listed some symbols of chemical apparatus and equipment normally used in a P&ID, according to DIN 30600 and ISO 14617.

**Symbols of chemical apparatus and equipment**
Pipe Piping Within industry, piping is a system of pipes used to convey fluids from one location to another. The engineering discipline of piping design studies the efficient transport of fluid....	Thermally insulated pipe	Jacketed pipe	Cooled or heated pipe
Jacketed mixing vessel (autoclave)	Half pipe mixing vessel	Pressurized horizontal vessel	Pressurized vertical vessel
Pump Pump A pump is a device used to move fluids, such as liquids, gases or slurries.A pump displaces a volume by physical or mechanical action. Pumps fall into three major groups: direct lift, displacement, and gravity pumps...	Vacuum pump Vacuum pump A vacuum pump is a device that removes gas molecules from a sealed volume in order to leave behind a partial vacuum. The first vacuum pump was invented in 1650 by Otto von Guericke.- Types :Pumps can be broadly categorized according to three techniques:... or compressor	Bag	Gas bottle
Fan	Axial fan	Radial fan	Dryer Dryer A dryer most commonly means:* Hair dryer* Hand dryer* Clothes dryer, also known as a tumble-dryer* Belt dryer* Cereal dryer, for food preservation* Desiccant, a substance that absorbs or adsorbs water...
Packing column	Tray column	Furnace Furnace A furnace is a device used for heating. The name derives from Latin fornax, oven.In American English and Canadian English, the term furnace on its own is generally used to describe household heating systems based on a central furnace , and sometimes as a synonym for kiln, a device used in the...	Cooling tower Cooling tower Cooling towers are heat removal devices used to transfer process waste heat to the atmosphere. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or in the case of closed circuit dry cooling towers rely...
Heat exchanger Heat exchanger A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...	Heat exchanger Heat exchanger A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...	Cooler	Plate & frame heat exchanger Plate heat exchanger A plate heat exchanger is a type of heat exchanger that uses metal plates to transfer heat between two fluids. This has a major advantage over a conventional heat exchanger in that the fluids are exposed to a much larger surface area because the fluids spread out over the plates. This facilitates...
Double pipe heat exchanger	Fixed straight tubes heat exchanger Shell and tube heat exchanger A shell and tube heat exchanger is a class of heat exchanger designs. It is the most common type of heat exchanger in oil refineries and other large chemical processes, and is suited for higher-pressure applications. As its name implies, this type of heat exchanger consists of a shell with a...	U shaped tubes heat exchanger	Spiral heat exchanger
Covered gas vent	Curved gas vent	(Air) filter Filter (chemistry) In chemistry and common usage, a filter is a device that is designed to physically block certain objects or substances while letting others through. Filters are often used to remove solid substances suspended in fluids, for example to remove air pollution, to make water drinkable, and to prepare...	Funnel
Steam trap Steam trap A steam trap is a device used to discharge condensate and non condensable gases with a negligible consumption or loss of live steam.Most steam traps are nothing more than automatic valves. They open, close or modulate automatically...	Viewing glass	Pressure reducing valve	Flexible pipe
Valve Valve A valve is a device that regulates, directs or controls the flow of a fluid by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but are usually discussed as a separate category...	Control valve	Manual valve	Back draft damper
Needle valve Needle valve A needle valve is a type of valve having a small port and a threaded, needle-shaped plunger. It allows precise regulation of flow, although it is generally only capable of relatively low flow rates.- Construction and operation :...	Butterfly valve Butterfly valve A butterfly valve is a valve which can be used for isolating or regulating flow. The closing mechanism takes the form of a disk. Operation is similar to that of a ball valve, which allows for quick shut off. Butterfly valves are generally favored because they are lower in cost to other valve...	Diaphragm valve Diaphragm valve Diaphragm valves consists of a valve body with two or more ports, a diaphragm, and a "saddle" or seat upon which the diaphragm closes the valve. The valve is constructed from either plastic or steel....	Ball valve Ball valve A ball valve is a valve with a spherical disc, the part of the valve which controls the flow through it. The sphere has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends...