Basic Flowchart Symbols and Meaning

The vector stencils library "Valves and fittings" contains 104 symbols of valve components.
Use these icons for drawing industrial piping systems; process, vacuum, and fluids piping; hydraulics piping; air and gas piping; materials distribution; and liquid transfer systems.
"A valve is a device that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically valves fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure.
The simplest, and very ancient, valve is simply a freely hinged flap which drops to obstruct fluid (gas or liquid) flow in one direction, but is pushed open by flow in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. ...
Valves are found in virtually every industrial process, including water & sewage processing, mining, power generation, processing of oil, gas & petroleum, food manufacturing, chemical & plastic manufacturing and many other fields. ...
Valves may be operated manually, either by a handle, lever, pedal or wheel. Valves may also be automatic, driven by changes in pressure, temperature, or flow. These changes may act upon a diaphragm or a piston which in turn activates the valve, examples of this type of valve found commonly are safety valves fitted to hot water systems or boilers.
More complex control systems using valves requiring automatic control based on an external input (i.e., regulating flow through a pipe to a changing set point) require an actuator. An actuator will stroke the valve depending on its input and set-up, allowing the valve to be positioned accurately, and allowing control over a variety of requirements." [Valve. Wikipedia]
The example "Design elements - Valves and fittings" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Chemical and Process Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "HVAC controls" contains 23 symbols of HVAC controls (sensors, actuators, timers, controllers, I/ O points).
"HVAC (... Heating, Ventilation and Air Conditioning) is a control system that applies regulation to a heating and/ or air conditioning system. ...
Central controllers and most terminal unit controllers are programmable, meaning the direct digital control program code may be customized for the intended use. The program features include time schedules, setpoints, controllers, logic, timers, trend logs, and alarms. The unit controllers typically have analog and digital inputs that allow measurement of the variable (temperature, humidity, or pressure) and analog and digital outputs for control of the transport medium (hot/ cold water and/ or steam). Digital inputs are typically (dry) contacts from a control device, and analog inputs are typically a voltage or current measurement from a variable (temperature, humidity, velocity, or pressure) sensing device. Digital outputs are typically relay contacts used to start and stop equipment, and analog outputs are typically voltage or current signals to control the movement of the medium (air/ water/ steam) control devices such as valves, dampers, and motors." [HVAC control system. Wikipedia]
Use the design elements library "HVAC controls" for drawing the HVAC system diagrams, controls drawings, and automated building control and environmental control system layuout floor plans using the ConceptDraw PRO diagramming and vector drawing software.
The shapes library "HVAC controls" is included in the HVAC Plans solution from the Building Plans area of ConceptDraw Solution Park.

The vector stencils library "HVAC controls" contains 23 symbols of HVAC controls (sensors, actuators, timers, controllers, I/ O points). Use it for drawing HVAC system diagrams, controls drawings, and automated building control and environmental control systems design. The example "HVAC controls - Vector stencils library" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the HVAC Plans solution from the Building Plans area of ConceptDraw Solution Park.

The vector stencils library " Biochemistry of metabolism" contains 46 metabolite symbols for drawing metabolic pathways maps, biochemical diagrams and metabolism process flow charts using the ConceptDraw PRO diagramming and vector drawing software.
"Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, catalytic activity of their own (usually as a cofactor to an enzyme), defense, and interactions with other organisms (e.g. pigments, odorants, and pheromones). A primary metabolite is directly involved in normal "growth", development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial microbiology. A secondary metabolite is not directly involved in those processes, but usually has an important ecological function. Examples include antibiotics and pigments such as resins and terpenes etc. ...
The metabolome forms a large network of metabolic reactions, where outputs from one enzymatic chemical reaction are inputs to other chemical reactions." [Metabolite. Wikipedia]
The shapes example "Design elements - Biochemistry of metabolism" is included in the Biology solution from the Science and Education area of ConceptDraw Solution Park.