hi All,
i have a question regarding local failure criteria in the example of ASME PTB-3, shown as below:
"5.3.2 Example E5.3.2 – Elastic Analysis
In addition to demonstrating protection against plastic collapse, the following elastic analysis criterion
shall be satisfied for each point in the...
hi all,
the salesman of my company checks with me if design-only certification is available under ASME VIIII-1.
many years ago, i accidentally heard that ASME would provide design-only certification to a company?
what is the current status? is design-only certification for ASME VIII-1 available...
hi, all,
a pressure vessel is designed to ASME BPVC VIII-1 or VIII-2, under what situation shall the creep analysis be mandatory?
At temperatures in the range where creep and stress rupture strength govern the allowable stress? if yes, i am confused why creep analysis is required while...
i am reading Interpretation "BPV VIII-1-19-11", and encounter a problem:
Background: A vessel has a 14" NPS nozzle which is 15mm (0.59") thick with a Category C butt weld between the nozzle neck and a flange. The nominal thickness at the welded joint does not exceed the thickness in UW-11(a)(2)...
i accidentally find one change of UW-11(a)(4) in ASME VIII-1 since 2019 edition.
UW-11(a)(4) of 2017 edition:
(4) all butt welds in nozzles, communicating chambers, etc., with the nominal thickness at the welded joint that exceeds the thickness in (2) above or attached to the shell or heads of...
hi, all
i've a question regarding MOC of a tower, which is constructed to ASME VIII-1
it's a deethanization tower with diamter of 2.5m, and height of about 50m，Design pressure 4.6MPa, Design Temp 150C， MDMT-70C.
i would like to fabricate the tower with a low alloy material.
i don't like to use...
hi all,
i come across an issue regarding how to exempt the fatigue analysis for the air cannons.
the situation is such that i am working with an equipment to which several air cannons are attached. the cannons are used to prevent accumulation of powder in the filter.
the air cannons are just...
Hi all,
it's regarding NDE of angle joint defined in ASME VIII-1.
angle joint is indicated as NA in table UW-12 regarding NDE, but i checked with engineer experienced in NDE, and find RT， and UT could be performed for angle joint in case that the diameter is large enough.
i am confused now...
Hi all experts,
we are implementing a project which locate alongside the sea. that means corrosion is serious.
recently, our corrosion engineer raise additional statement that "hot dip galvanized bolts are forbidden on Stainless Steel vessel", even the operating temperature is ambient.
the...
hi, all
i encounter an issue when reading UCS-68.
UCS-68(c) states that "The resulting exemption temperature may be colder than −55°F (−48°C) when the
PWHT exemption in (b) is applicable.".
what does that mean?
i have an example offering where the issue lies:
a vessel constructed of SA-516 70N...
hi, all experts,
it's about UCS-67 in ASME VIII-1.
i read "CASTI Guidebook to ASME VIII-1", and find the following statement:
"When the minimum design temperature is less than -55°F (-48°C) and the parent
materials are exempt from testing because of a low coincident ratio, the weld is still to...
hi all,
i am reviewing a calculation of the MDMT of the forged neck.
it's about how to determine the governing thickness.
it's a forged nozzle constructed of SA-105 produced to fine grain practice and normalized heat treatment.
it's butt welded to the shell constructed of SA-516 70N, which is...
hi all,
i've a question regarding to UCS-66 in ASME VIII-1:
it's a heat exchanger constructed to ASME VIII-1 with MDMT -50C.
may i use SA-36 for the tie rods in tube bundle?
per my experience, SA-36 is not suitable for such cold temperature, but i find the following paragraph:
UCS-(b)(3) When...
hi,all,
i encounter a problem regarding to determination of MDMT per UCS-66.
it's nozzle welded into shell. the nozzle and shell are evaluated based on their governing thickness, and UCS-66 curve respectively. i am clear with it, just how to deal with the tg1,tg2,tg3 in figure UCS-66.3(b)...
hi, all,
my colleague come to me with a question, that he have a tubular exchanger with the channel side subjected with cyclic loading. the operating pressure ranges from 0 to 0.3MPa, and the design pressure is set at 0.6MPa。the operating temperature is not high, around 170C。
according to the...
hi experts,
i am checking a FEA REPORT of a buffer tank designed to asme viiii-1. in the meantime, the buffer tank is subjected to cyclic loading, thus VIII-2 part 5 is referred to evaluate the risk of fatigue failure.
and now i have following inquiries:
1, is it mandatory to check other...
Hi all,
it's known that thermal stresses are stresses that result when a temperature change of the material. there is a general practice in this industry that people just consider the thermal stress resulting from thermal gradient.
we never consider thermal stress due to material elevated to...
hi all,
it is a question about steelmaking of SA-105.
i have an experience that the SA-105 I purchased are always normalized even without prior requirement.
and what about fine grain practice? will the Steel Mill perform fine grain practice as default?
In other words, what is general practice...
hi, all,
this is a question related to corrosion of SS under high temperature ammonia gas.
It's the AIG(Ammonia Injection Grid)in the Boiler system, which funcitons to control the NOx in flue gas by injecting gaseous ammonia of a high temperature around 400C.
the Ammonia distributing pipe are...
hi all,
we have flanged joint with ring type joint. flange is 304, ring type joint 304 too. we mandate that the hardness of flange shall be larger than that of ring type joint by min.30HB.
now the materials are purchased already, and test result is beyond original expectation:
the hardness of...
