Pipis118 If it has been reported that the Pressure-relief Valve opened 10% above its CDTP, then that is cause for alarm.
A Pressure-relief Valve will have a tolerance for the set pressure (the pressure the valve starts to open. CDTP - is the test bench pressure - Cold Differential Test Pressure...
OP Changed weight from 150 kg to 60 kg without highlighting the correction in the post. Such holders should have threaded connections on their periphery to allow use of eye bolts etc., as Shvet had earlier alluded to. But if you can't remove the vertical tubes above, you may have an issue with...
Dumb comment...Reverse of how they were installed? Photo's etc., would be helpful.
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
See attached extract below from current ASME I (2023) Scope, particularly paragraphs PG-2.1(a) and PG-2.2.
Do also understand that a ASME I safety valve has different operational characteristics compared to a more simpler ASME IV valve, for example ASME I requires full opening at 3%...
You are again referring to extracts from an out of date ASME VIII document.
Also you're still confusing the issue. Capacity tests at 'up to 120%' are for the relief conditions specifically mentioned in (old) UG-125 (c)(3). You seem to be picking out sections to suit your narrative. What exactly...
@goutam_freelance No. You are confusing capacity certification, which is required to be done at 10% overpressure, with operational overpressure.
FYI. UG 131 was transferred from ASME VIII to ASME XIII in 2021. In any case (old 2019) ASME VIII UG 134 allowed setting of 105 % of multiple valve...
You should be specifying the set pressure/overpressure as follows;-
Existing Valve Set @ 100 + 16% overpressure = 116
Additional Valve Set @ 105 + 10% overpressure = 115.5
The relieving pressure is considered equal here (as in API/ASME). See API-520 Part I, Table 6
NB: PSV's do not have 'set'...
To answer you;-
1) Will the additional PSV be capable of relieving at 5% overpressure? (certification of capacity per ASME would be at 10% overpressure). Generally, if you do not exceed 105% of the second valve, you are within code rules. Why do you want to match the set pressure of the first...
MESC SPE 77-302 - Valves, General Requirements
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
I can't comment in detail on this, but this extract from API 520 Part II (2020) may answer your concern.
Note that there is a separate safety relief valve forum on eng-tips.
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
***...
Best if you repost this in the safety relief valve forum section and delete this post.
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
My question was, where in ASME XIII Appendix B, is the reference for N+1 written?
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
Where are you getting N+1 from? Please be more specific, there is no mention of N+1 in Appendix B that I can see.
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
I can't see anything in the referenced standards. Not even in ASME XIII, ISO-4126 or NBIC-13. Note that none of the statements made in API are mandatory. It is up to the user to follow them. API-576 is also relevant for later maintenance not necessarily for manufacturer shipping. All...
You say you are trying to calculate for the purpose of 'Trevitesting'.
Trevitesting is the trade name of the 'in-situ' testing of Pressure-relief Valves by devices made only and licensed by the company Furmanite.
The generic term is In-Situ Testing.
For In-Situ Testing, it is the nozzle seat...
It really comes down to the practicality of what you are shipping. Sure it is recommended that Pressure-relief Valves are shipped in the upright position, with the spindle vertical. However, this is not always possible, due to packing, logistics, lifting etc. etc. I can tell you that when I was...
No red line appearing.
What is it you are trying to achieve from this?
*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***
*** 'Pressure-relief Valve' is the ASME/API used term ***
You should now be using ASME XIII for Pressure-relief Devices.
You are referencing a section in ASME VIII which has since 2021 been taken out and replaced by ASME XIII.
Refer to table 3.6.3.1-2 in ASME XIII for the current legislated set pressure tolerances.
(The 2nd statement you referenced...
'Back in the day......' after we hydrotested, we simply aimed a heating blower to the valve outlet until the inside was dry. This took 30 - 45 minutes depending on size etc. These were Pressure-relief valves which can also accumulate water etc., in pockets and crevices. Once dry, we reapplied...
As LittleInch has stated, the material is not listed in the main specifications. I did find this where I guess the supplier has calculated the pressure ratings. Use this with caution as there is no reference how these values were determine (tabulation in lower part of the web page) - Use for...