Instrument HOOK- UP drawing basics

What is hook-up drawing?

Hook up drawing provides a detailed description of the installation of the instruments in the correct way, from the tapping point in the process line up to the sensing instrument.

The Hook-up drawing indicates the slopes of the tube, the position of the instrument in reference to the point of tapping of the process, the breakage of the reach between the instrument and the pipe. It also provides information on the requirement of bulk material for each installation.

There are two types of hook-up drawing:

Process Hook-up: which contains the installation of the instrument for process control.

Pneumatic Hook-up: This hook-up drawing contains typical installations for instruments that require air for instruments, such as the control valve.

Difference between Hook-up and P&ID drawing:

Piping and Instrumentation Diagram (P&ID) shows the instruments that are to be connected to a process line, the Instrument Hook-up gives detail information about how that is to be done during actual installation.

Requirements for a Hook-up drawing:

  • Contract Requirement and Project Design Criteria
  • Piping and Instrument Diagrams (P&ID)
  • Instrument List (with Instrument Datasheet)
  • Piping Material Classification (PMC) or Piping Material Specification (PMS)
  • Instrument Rack grouping, elevation of tapping and rack
  • Control Valve List (for Instrument Air)
  • Tank and Heat Exchanger GA drawings

Example for a Hook-up drawing:

Process Hook-up:

Hook- up for pressure transmitter:

Hook up drawings: Hook Up Library.pdf (1.7 MB)

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In our works, it is most time consuming and tedious job to do.