by Piping isometric drawings is the term used for automatically generating spool sheets, complete with bills of materials (BOM) for pipe spool fabrication which satisfies the process requirements. Isometrics are modelled and generated from 3D model software into 2D drawings (isometric sheet) which is used for fabrication by construction subcontractor.
An isometric usually shows a complete line from one piece of line or equipment to another. It gives all information necessary for fabrication and erection of piping.
Items and information to be shown on an isometrics include:
- North arrow (Plant north)
- Dimension and angles
- Line number, direction of flow ,insulation and tracing
- Equipment number and location of equipment’s
- Details of flanges equipment nozzles on equipment to which piping has to be connected
- Size and type of every valve
- Size , pressure rating and instrument number of control valve
- Number , location and orientation of each instrument connection
- Shop and field welds for shop fabrication and field erection of materials and fabrication.
- Isometric sheet continuation numbers
- Unions required for installation and maintenance purposes
- Materials of construction
- Location of vents ,drains and traps
- Location of supports and identify by pipe support number
- Bill of materials
