Statistics might help - were the 1% affected parts all from the same cast? Were they from the same production run (the grinding and cleaning phases)?
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Note that the designation 1.4542 will be found in various EN standards depending on the product form. For example:
EN 10088-3 covers semi-finished products, bars, rods, etc.
EN 10088-2 covers sheet, plate and strip.
EN 10028-7 covers sheet, plate and strip.
There may be others...
Thanks Steve,
Your reply would suggest that all carbon and low alloy steels should always be tested for HIC whether they fall into Appendix A.2 criteria or not. This makes the clauses that say no additional testing is required is mis-leading since you always have to test for HIC (but not...
My question concerns the use of carbon and low alloy steels in H2S-containg environments. The H2S in my case is low - 10ppm - and conditions fall into Region 0 of Figure 1. Therefore Clause 7, Option 1 applies, and it covers SSC, SOHIC and SZC (from the clause title).
Clause 7.1.1 of the...
You might consider laying some weld beads on the surface of the trays. There is some trial and error involved so you try it on some samples sheets first to get a "feel" for how much distortion can be removed for a given thickness of sheet/plate and the size and length of weld bead...
Are you sure the mumbers are correct?
The numbers you quote are similar to BS EN 10088-1 designations.
X5CrNi18-10 is a 304 steel
X5CrNiMo17-12-2 is a 316 steel
Note that if Mo is present an extra numeric digit is added - in this cae "-2" to indicate a nominal 2%Mo.
The BS EN (at least my issue...
Thank you for your reply. I agree with what you say - that metallurgically API5L Grade A or B would be OK in Region 0. However, the MR0175/ISO standard appears to ask for more than "off the shelf" Grades A and B (see previous post). This means that even for an environment with a few ppm H2S I...
Can API5L Grade A or B pipe be used for Region 0 in Figure 1 of NACE MR0175/ISO15156-2 2009 without calling up any special requirements?
The impression given in the NACE document in Clause 7.1.1 and 7.2.1.3 is that no special precautions are needed but then goes on to list General Requirements...
Thanks for your replies. I had previously checked the Outokumpu and Nickel Institute (as well as the Kreysa & Schutze Corrosion Handbook, the NACE Corrosion Database and a few other sources but couldn't find nitric acid/ hydrogen peroxide mixtures - either chemical on its own is OK at the...
Does anyone have experience of or could point me to a reference on the corrosion of austenitic stainless steel (304L and 316L) in 40% nitric acid/30%hydrogen peroxide mixture at 50 deg C? My instinct is that, as these are both oxidisers , the stainless steel would be OK but I'd would prefer to...
Metengr's data can be found in the brochure at http://www.hpalloy.com/alloys/brochures/Nitronic60book.pdf
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I would check first that you actually do have any iron contamination. A ferroxyl test (ASTM A380) on some finished parts would show whether you have a problem.
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Would a check for radioactivity help here? Some years ago I recall some manufacturers of gamma radiation monitors seeking pre-nuclear age steel since all steel since the start of atmospheric testing contained radioactive contaminants which interfered with the calibration of the monitors. I would...
In my experience, there is little difference in the nitric acid resistance of 304L and 316L (which can have 2.0-3.0% Mo) at low temperatures (say less than 60 deg C). It's only when higher temperatures are encountered that the molybdenum content has a detrimental effect. So don't be concerned if...
Buy two equal tees and cut them longitudinally down the long run - discard these "backs" of the tees and weld together the other halves with the branches on.
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Thinning of elbows on the outer radius (extrados) is common. Some manufacturers will manufacture them from pipe of the next schedule up. For example, they might use shedule 40 start pipe to make a schedule 10 elbow, schedule 80 for a schedule 40 and so on. I should think large manufacturers will...
To calculate allowable stresses in PD5500, the minimum 1% proof stress for the material (in my case stainless steel 1.4307 - also called 304L) is divided by a factor of 1.5 (clause 2.3.3.3(b) of PD5500). For steel 1.4307 this gives an allowable stress at temperaures below 50 deg C of 153MPa...
One of the purposes of the Quality Plan or Inspection and Test Plan is to resolve the questions you are asking. Each of the parties involved defines precisely what they are doing, how often, and by whom - the people carrying out the various inspections, tests and examinations must be suitable...
