Susielu182
Mechanical
- Aug 10, 2022
- 1
Good Afternoon,
I have a customer who is wanting to re-rate an Air Cooled Heat Exchanger that was built in 1992. The header boxes have (3) pieces of plate (0.5" thk x 8.25" x 5.5") welded in between the tube rows on each side. I do not think these are stay plates as they do not run the entire span of the header box. We cannot get this header box to pass Appendix 13 calculations at the current rated pressure, as the end caps are not thick enough (calcs are showing should be at least 1" thick, and they are 0.75" thick). My question is, are these "Tie Bars" installed as extra reinforcement for the end caps to reduce the required thickness? If so, are there calculations somewhere for this? Snippit of the Tie Bars attached.
Susie S.
I have a customer who is wanting to re-rate an Air Cooled Heat Exchanger that was built in 1992. The header boxes have (3) pieces of plate (0.5" thk x 8.25" x 5.5") welded in between the tube rows on each side. I do not think these are stay plates as they do not run the entire span of the header box. We cannot get this header box to pass Appendix 13 calculations at the current rated pressure, as the end caps are not thick enough (calcs are showing should be at least 1" thick, and they are 0.75" thick). My question is, are these "Tie Bars" installed as extra reinforcement for the end caps to reduce the required thickness? If so, are there calculations somewhere for this? Snippit of the Tie Bars attached.

Susie S.