Yes, remaining lower pressure side test is conducted on site after replacing new bundle inside of existing shell.
Higher side pressure test conducted in shop before coming new bundle to site eliminates risk of on site major problems.
We have hydrostatic testing equipment or we make spare channels or shell for hydrostatic testing of new bundles in the shop.
Depending on which side, tube or shell side, is higher, only the higher side is hydrostatically tested in the shop.
In cases where we do not just make the shell for...
Thanks for replies.
Actually i wanted to know that how much we can drill tubesheet and after drilling and completion of pulling and putting bundle in service, do we need plug hole that we drilled for prevent decrease tubesheet strength and preventing any leak...
Dear Experts,
If we drill tubesheet for blind tapped hole for pulling out bundle. Should we plug with bolt this blind tapped hole.
ASME Section VIII UG-43(d) states "The distance from the inside sur-face of the vessel to the bottom of a drilled hole to be tapped shall not be less than the...
Hello,
Thank you for advice.
As you mention, we decreased tube test pressure and started tube test with 4 bar and increased it to 8 bar step by step. It leaked at 8 bar.
We will perform rolling works in the tubesheet. I hope, rolling will be solution for us.
Best Regards,
Hello,
I would like to ask a question about hydrotesting.
We have a fixed tubesheet heat exchanger in our facility and it pass shell hydrostatic test at 9 bar but it fails when we test tubes at 9 bar.
Pressure gage decreases and we observe a leakage shell drain. What is your recommendation...
Hello Dear Experts,
1. In April-2017, Etan Cracking furnace tubes, U elbows and hanger supports were completely renewed as planned.
2. On August-2019, the furnace was stopped to decoke. As a result of the inspection activities, the magnetization results were found to be normal and the percent...
We detected many pitting corrosion areas after cleaning solid Phthalic Anhydride layer and consider this layer causes under deposit pitting corrosion? What is your opinion?
Drum is not old. A285 GrC material with 8mm thickness.
It was built in 2014 and not expected corrosion in such short time. Before this drum, former drum worked 35 years and corroded internally and externally and renewed in 2014. I do not have detailed information. I also consider improper...
Hello,
We observed a leakage in the shell of Ageing Drum Phthalic Anhydride (PA) plant.
After inspection of inside of Carbon Steel material shell, severe corrosion can be also seen in other areas. I consider that phthalic acid occured and metal corroded.
Operation team indicates that there was...
Hello,
Could you help us to find out our seperator material related specifications? It can be seen below chemical composition.
DIN 40NiMoCr10 4 is a specifications that i could find closest specifications.
Is there any welding recommendations for this material?
Best Regards,
Hello everyone,
I could not find ASME 31.3 Category M service examination paragraph.
Table 341.3.2 Acceptance Criteria for Welds — Visual and Radiographic Examination. Normal fluids and Category M are in same column.
Under the "341.4 Extent of Required Examination" it can be seen that Normal...
I mean when internal pressure 27 kg/cm2 and max temp 860 C. No problem.
But when full vacuum condition occurs, we should not exceed 121 C.
i understand full vacuum condition definition as if steam condensates internal pressure will be 0 and we have existing external pressure 15 psi.
