Hello All,

we are having doubts about the reinforcement of nozzles if the re-pad is double (2 plates welded) and it is in the same side. We thougt that is possible to add 2 reinforcing pads of different diameter, in the same side of the shell, but we can't find it in the Asme-VIII Div 1.

The problem is because we have plate of thickness 10mm, and we need almost double thickness for the reinforcement, so we want to make the most of the available material, welding it in 2 different layers.

Has anybody some experience in this? We have seen in FIG UW-16-1 (a-3) an acceptable design with internal and external reinforcing pads, and we are figering out if it is the same case.

Thanks in advance,

Best Regards

IgnacioMPereda,
Hi ya,
i feel uncomfortable with your 'sticker pads' on single because we can not ensure that the integrity of the pad. if i'm you, i will rather look for thicker pad for example 20mm for single side or 10mm at outer and 10mm at inner. anyhow, it was just my opinion. you have to check it with your AI wheter he or she accept or not since the code silence about this.

Best regards

Ignacio,

Just like kkchong, I feel very uncomfortable about double-layer repad. Recently, I had to design the reinforcement for 2 huge nozzles, that were close to each other. I've considered to use an internal pad - which leads to maintenance problems, since it may become difficult to clean - and also a double repad - a partial second layer, between the nozzles.

Even considering that the Code seems to consider everything inside the limits as useful reinforcement, even after FEM analysis of the arrangement, I was not confident to use these solutions. In my case, I used an analysis according to UG-42a) e App 1-7a, using necks and a repad as thick as possible.

Carlos Filgueiras