PID diagram is the abbreviation of Pipeline Instrumentation Flowchart (Process & Instrumentation Drawing), which refers to the use of uniformly specified graphic symbols and text codes to represent in detail all equipment, instruments, pipelines, etc. of the system. Drawings of valves and other related utility systems such as: conventional sewage treatment, power generation systems, heating condensate solutions, and central air conditioning systems.
The pipeline instrument flow chart is based on the process design. It is an important part of the engineering design and the main basis for the relevant majors in the engineering design.
Pipeline and instrument flow charts use uniformly prescribed graphical symbols and text codes to diagrammatically represent all the equipment, instruments, pipes, valves and main pipe fittings required to establish chemical process equipment, according to their respective Functions are combined to meet process requirements and safety and economic purposes to describe the structure and function of process equipment.
It is not only the basis for design and construction, but also part of the complete technical data required for business management, commissioning, operation, maintenance, start-up and shutdown, etc. Piping and instrumentation flow diagrams help simplify the exchange of information between the various departments tasked with the development, engineering, construction, operation, and maintenance of the process unit.
General design regulations for pipeline and instrument flow charts:
Drawing specifications
Drawings should adopt standard specifications and have a unified title bar with the name of the design unit. When cooperating with a foreign company and it is necessary to modify and deepen the design on the drawings provided by the foreign company, a title block with the name of the unit can be stamped next to the title block of the foreign company's drawings.
Generally, No. 0 (A0) standard size drawings should be used, but No. 1 (A1) standard size drawings can also be used. Only one specification of drawings can be used for the same device, and lengthening or shortening is not allowed (except in special circumstances).
Lines
All lines should be clear, smooth and even, with sufficient spacing between lines. The minimum spacing between parallel lines should not be less than twice the width of the widest line. , and shall not be less than 1.5mm, preferably 10mm. On the same drawing, the width of lines of the same type should be consistent, and the width of a line should not be less than 0.25mm under any circumstances.