Is there any limitation in code regarding hydrotest a vertical vessel in horizontal position.

Is my interpretation correct that code is silent about this.

The Code says (UG-22) you have to consider all possible loadings. This includes that you have to assure an adequate support during the hydrotest to avoid excessive stresses induced into the shell.

Michael

Yes, you are correct.
No limitations, right now however, keep up with revisions to the Code.

Also see Appendix W, "Note 4" and "Note 39"
The reason these notes are there is so that anyone reading the Manufacturer's Data Report will not be confused.

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