Welding of steam tracing to tank cone

[CobusvanJ]

Hi,

I have the following problem: The design of a new tank calls for steam tracing to be welded by continuous welding on both sides to the bottom cone of a tank which will need to ensure product inside the tank does not cool down if there is a failure.

The cone is 12mm think SA-516 Gr.60N, and the steam pipes are 1" Sch.160 SA-106 Gr.B.

The concern is that the heat input of continuous welding on both sides of the steam pipes to the cone will cause the cone to warp.

A proposal was made to use staggered welding and then fill the gaps between welding with a heat transfer compound to make up for the loss of transfer area that would be provided by continuous welding. Can anyone propose a compound to be used that can handle up to 181deg C, bonds sufficiently to steel but is still removable and has decent heat transfer properties?

Or perhaps another solution?

 

[QMax1]

The best heat transfer coumpounds out there are terrible conductors...but they're better than air. When applying to pipe on a vessel, you will see a some improvement over nothing at all. Trouble is it may not last very long. You will want to capture the HTC somehow so it will be a longer term solution. QMax Industries, Inc. offers the HTC at the temperatures you need. They also may have a more permenant solution.

 

[SceneryDriver]

Would brazing be an option, with its potentially lower heat input, in comparison to welding? Can you talk weld the steam tracing pipe, and then fully bond with a braze, or even a solder? How hot must this get (hot enough for steam, I presume) and what are the other environmental concerns?



SceneryDriver

 

[StoneCold]

Why would you weld pipe to the cone? Wouldn't the correct method be to add a half pipe jacket to the outside of the cone? If that is too much stress, switch to a dimple jacket on the cone. Both of them seem like a better solution than heat transfer pastes.

Regards
StoneCold