Piping and instrumentation diagram (P&ID) legend sheet originally developed for an HF alkylation unit at an oil refinery. This CAD drawing provides a standardized set of symbology for industrial process drafting, covering misc. piping, valve types, and instrumentation control systems.
The file includes a wide variety of valve symbols including gate, globe, check, ball, needle, and relief valves, alongside multiple actuator types such as diaphragm, piston, and solenoid. It features detailed identification tables for line services (caustic, instrument air, natural gas, etc.) and specific piping specifications for hydrocarbon and HF acid services (B1A1, H2A2). Instrument identification follows standard lettering conventions for measured variables and passive functions.
Additional components include signal conditioning symbols, common industrial abbreviations, and a revision history tracking plant expansion updates. The second sheet provides equipment blocks for pumps and heat exchangers, including standard revision and title block templates used in refinery documentation.
