P&ID schematics 1

Basic Piping and Instrumentation Symbols

Lesson 1

The contents flow toward the point of the triangle.

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​An inline pump symbol

The black colour indicates that the valve is generally closed. If the triangles were white, the valve would be open.

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Closed valve

Valves allow us to adjust the flow of air or fluids through a system. Describe the symbols in English; make the others guess your valve!

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​Examine the different valves

Here we have an expansion tank with two open valves. a An expansion tank is a small tank used to protect closed water heating systems and domestic hot water systems from excessive pressure. The tank is partially filled with air, whose compressibility cushions shock caused by water hammer and absorbs excess water pressure caused by thermal expansion. (Wikipedia)

​Expansion tank

​It separates two or several networks.

​​The Hydraulic Compensator

​a device used to measure the pressure of air or gas in a specific system or container. (P is for PRESSURE)

​​Air gauge or manometer

An air heater (also referred to as air preheater or regenerative air heater) is a common component of large boilers with the purpose of increasing its overall efficiency.

​ (chemeurope.com)

​Air heater

a control device prevents trapped air from becoming a problem in a system.

​From Hawle.com and hynds.co.nz

An Air Valve

a valve used to control fluid flow by varying the size of the flow passage

​Wikipedia

​Control Valves

is used to measure the force of heat in a machine or application

​Temperature Gauge or Thermometer

an industrial valve with a steady flow rate used for diversion or mixture of applications. It's also known as a multiport valve because of its three openings which can be connected to tubing for the flow of liquid or gas.
From DomBor Valve

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A three-way valve

A safety group is the regulator for the pressure of a hot water tank. Water expands when heated, which causes increased pressure in a closed system such as the tank. In order to prevent this from leading to unwanted surprises, the safety group, with the help of a valve, drains water when the set pressure is exceeded.

​From Hieper.de

​The Safety Group