Pipe color is set to gray but is displayed as orange (same color as valve or beams)
Also when viewing the Code Stress color plot the pipe is grayed out:
The following was logged, CAE-TR-11078 - Beam color is used for pipes when beams are hidden.Product Version: 9.5.1 Corrected Version: 9.6.0.14
Graphics
Bentley AutoPIPE