Usually, Cut-outs between platforms or grating are not given due importance as they can be done on-site.
While we have such an approach, there is a concern that could go unnoticed.
This concern is regarding corrosion.
Let’s understand this by taking a practical example.
Platform or Grating for Field Instruments
Below is a Diagram of a Vacuum column with 2 platforms/ gratings.
And we have placed a DP transmitter on platform/grating number 2, but HP tapping of transmitter is on grating/platform 1.
And we require cut-out for the same.
Usually, for corrosive environment, the materials that are specified are “Hot dip galvanized”.
So when you have fixed all the gratings etc on the tower and then decide to drill the cut-out then the edges get exposed.
These cannot be hot dip galvanized at this stage hence they are just painted.
Paint is temporary solution as compared to Hot dip galvanization.
Hence when the paint gets peeled of gradually along the edges, it would get corroded and would eventually turn into a safety hazard.
So in conclusion cut out of grating left to site personnel will have its edges painted which is not at par with being “hot dip galvanized” hence corrosion can gradually creep into it.
These corroded edges could cause injury to the site personal.
Hence prefer giving cut out during the manufacturing of this gratings so that the edges are also hot dip galvanized.
Thanks for reading.
Author: Asad Shaikh
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