Seal clamp for floating roof

[prashanth5723]

Hi all.
Attached an image showing the seal clamp details. Question is whether we need to overlap the seal clamps as shown in the image? Or can we use separate clamps without overlapping one over another? what will be the impact on the seal system if we don't overlap seal clamps?

 

[IFRs]

The vendor should have included drawings and/or instructions. These look like they were intended to be overlapped as you have installed them. The tank diameter looks large - the clamps show no angle between them. Apparently the vendor expects you to drill through the wiper? Or did they supply the wiper with holes? One issue you may have is that the holes are not uniformly spaced, making pre-fabricating the wiper with holes harder. Evidently the vendor thought the clamps were cute but did not consider the field issues. As you no doubt know, the wiper must be able to accommodate plus and minus 4" of tank shell variance. When the wiper is extended out 4 inches, the outer circumference is longer than the circumference at the bolt holes. Normally this means that for proper operation the holes in the wiper must be some small amount further apart than those on the mounting surface. This incremental distance is not just the ratio of radii but also takes into account the wiper material, operational considerations and tank size. Since the bolts are not on one consistent spacing this presents more work for the field crew. But, the clamps do look cute! Best advice: find out what the vendor intends you to do, hopefully they will have drawings, installation guide and splicing instructions. If the vendor can't or won't help, when you are done with this nightmare, find another vendor.

 

[prashanth5723]

@IFR. Many thanks for your reply. But what I want to get clear is whether generally (in any vendor's IFR) we need to overlap one clamp over another or can we clamp without overlapping?

 

[IFRs]

I don't overlap my wiper clamps if that helps. They come within 1/4" of each other though.

 

[prashanth5723]

@IFR.Thank you