I need help with a question

Generally, PG stands for **process gas**. For more details, refer to HG20519.36-92. 1. Method of compilation: The material code is formed by taking the initial letters of the English names of the materials based on their names and states. It is generally represented by 2 to 3 uppercase English letters. 2. Codes for process materials: PA – process air; PG – process gas; PGL – process material in gas-liquid two-phase flow; PGS – process material in gas-solid two-phase flow; PL – process liquid; PLS – process material in liquid-solid two-phase flow; PS – process solid; PW – process water. 3. Codes for auxiliary and utility system materials: (1) Air: AR – air; CA – compressed air; IA – instrument air. (2) Steam and condensate water: HS – high-pressure steam (saturated or slightly superheated); HUS – high-pressure superheated steam; LS – low-pressure steam (saturated or slightly superheated); LUS – low-pressure superheated steam; MS – medium-pressure steam (saturated or slightly superheated); MUS – medium-pressure superheated steam (saturated or slightly superheated); SC – steam condensate water; TS – heat-tracing steam. (3) Water: BW – boiler feed water; CSW – chemical wastewater; CWR – recycled cooling water; CWS – fresh cooling water; DNW – desalinated water; DW – drinking water and domestic water; FW – fire-fighting water; HWR – hot water return water; HWS – hot water supply water; RW – raw water/fresh water; SW – soft water; WW – production wastewater. (4) Fuel: FG – fuel gas; FL – liquid fuel; FS – solid fuel; NG – natural gas. (5) Oils: DO – waste oil; FO – fuel oil; GO – packing oil; LO – lubricating oil; RO – crude oil; SO – sealing oil. (6) Refrigerants: AG – gaseous ammonia; AL – liquid ammonia; ERG – gaseous ethylene or ethane; ERL – liquid ethylene or ethane; FRG – freon gas; FRL – freon liquid; PRG – gaseous propylene or propane; PRL – liquid propylene or propane; RWR – recycled chilled brine; RWS – fresh chilled brine. (7) Others: DR – drainage/bleed; FSL – molten salt; FV – flame exhaust gas; H – hydrogen; HO – heating oil; IG – inert gas; N – nitrogen; O – oxygen; SL – slurry; VE – vacuum exhaust gas; VT – vent. 4. Rules for the use and addition of material codes: Depending on the specific conditions of a project, the codes for auxiliary and utility system materials can be used as process material codes ； New material codes can also be added as appropriate, but they must not be identical to the material codes specified above. For example, in the plant for producing synthetic ammonia from natural gas, the supplementary codes for the process materials are as follows: AG – gaseous ammonia; AL – liquid ammonia; AW – ammonium water; CG – conversion gas; NG – natural gas; SG – synthesis gas; TG – exhaust gas

In a process diagram, PG stands for the field pressure gauge.

I’m dizzy! What kind of process do you use? How is it possible that you don’t even know this?

Since it is marked on the instrument’s flow diagram, PG should refer to Pressure Gage (an on-site pressure gauge). PG has different representative meanings in various fields. Please have the original poster confirm.