All,
In the process safety space, I often hear of these three factors (People, Plant, Process). What is slightly confusing to me is the delineation between the three. For example, is a procedure covering valve operation process or plant related?
Does anyone have any clear definitions of these...
Have a query with regards to high energy piping, on thermal power stations and creep damage.
There is much data available with regards to how to classify creep damage - we tend to adopt the VGB TW-507 criteria for the relevant materials, which is essentially a 1 (no creep voids) to 5...
Is anyone familiar with above grade and how it's corrosion resistance compares to 304, particularly in regards to SCC? From what I gather, the grade has slightly lower cr and ni, with a 1-2% addition of Cu. supposed to have better workability characteristics.
Thanks
I'm sure the question has been asked before, but what is the minimum hold time for PWHT on P91? The question is pertinent to thin sections (1/2" and lower say).
I believe ASME VIII (UCS-56) suggests it is possible to do as little as 15 mins on thin sections (<1/4"). However, I've seen some...
Does anyone have much experience with the above topic? Specifically, has anyone run successful life assessment programs at their plants based on creep pip measurements on pipework? Concerned about the quality of the measurements, given how easily the tips may be damaged and how accurate the...
See
thread794-302393
Have just been informed by some experienced power station personnel that this was reasonably common practice (using a lower alloy content - F11 - to perform capping runs to a F22 stub weld) to improve ductility and reduce the onset of fatigue cracking. Any truth to that...
Folks,
Have a stainless steel fitting, small valve welded to a pipe section, maybe about 3/4" in diameter.
The operating conditions it sees internally are 260C, 600 kPa.
Was told by operating personnel that the line suffered from an impact, which caused failure.
Material analysis has shown...
Haven't worked with ball valve failures too much, so I thought I should ask for some thoughts on this forum.
Came across a recent failure of a 1" NB ball valve, the downstream set had experienced severe gouging in a 180 deg arc. The gouging was sharp and distinct. Outside the gouge, the...
Two Questions:
1. What factor(s) limit the use of cast iron in higher temperature applications? Is it the debonding of the graphite phase from the matrix?
2. Is there any difference in the max servicable temperature for gray iron vs ductile iron? If so, why?
Questions are regarding use of cast...
Does anyone know what the applicable test standard is for subject?
ASTM B23 goes into some detail regarding specimen size and test limits without actually offering a standard for testing.
Any insights would be much appreciated.
Regards
All,
Have a vessel with a set in protrusion - the protrusion is welded to the shell using a double J-prep, full pen.
The vessel wall is approximately 100 mm thick, the nozzle and shell both carbon steel material (low C, < 0.2%).
Have recently encountered cracking on the weld toe, shell side...
We have a number of high temperature headers made from 2.25Cr 1Mo steel. They are stubbed with similar material. The branch welds connecting the two use a matching consumable although recent material identification suggests that the final weld run (on the stub side, furthest from the header)...
All,
I'm in the process of drafting a procedure for material sampling of high temperature headers in boilers for the purposes of performing accelerated creep testing.
Was wondering if anyone had any useful references.
Regards
kclim
I'm struggling to find where the mechanical property requirements (tensile, hardness, elongation) are for T22 material. Properties are listed for some of the other grades in the A213 standard however.
Is this intentional? If so, are there any adopted standards as far as mechanical properties...
Have a query regarding on above subject, mainly as it applies to the power gen industry (turbine valves).
My understanding is that it is common practice to apply stellite 6 on alloy steel spindles to prevent oxide build-up and associated jamming.
How critical is dilution given the application...
After info on the series of white metal alloys. In particular, the difference between the various grades, how 'brews' have developed over the years and physical properties (in particular, regarding thermal expansion).
Any links to resources or first-hand experience/knowledge would be much...
We are looking for a non-destructive method to determine the thickness of a stellite weld overlay on tubing. Does anyone have any experience with this?
We're looking at performing a weld repair on a valve seat. Valve body is a Cr-Mo material. Proposed method of repair is to remove damaged Stellite 6 layer and buttering (Inconel 625) layer, and reapply buttering layer and Stellite 6.
Was wondering what the requirements for the buttering layer...
In a previous post, I mentioned that I was looking at the difference between two phenolic resin components - one OEM and one original.
What we found was the resins were essentially the same apart from an additive - phthalic anhydride vs tetrahydrophthalic anhydride.
These compounds were...
