While API may relevant here, of more relevance is ASME. ASME DOES require a relief valve in this scenario.
Then utilizing normal relief valve "case" analysis your first relief valve should be sized for "blocked flow". The need for this relief may depend if there is another relief valve upstream...
My goodness this is not that hard.
The 10% rise in head to shutoff is specified to protect pumps in parallel operation. Otherwise the pumps can become unstable and ultimately cause damage.
Look up the McInnally institute and find the section on parallel pump applications
The outlet pipe rating does NOT have to be the same as the inlet pipe. In fact the PSV itself will not be provided in that manner. It will be provided with the lowest pressure class.
I am not sure about the EU / EC system but the for the ANSI / ASME system that will be 150#.
The whole question...
I don't believe that would be the case. It all depends on the "corporate" pipe code. For the system I have utilized valves 2" (50mm) and under shall be welded (I still prefer flanged for 2"). 3" (76 mm) and above shall be flanged.
For the ASME systems flanged valves are utilized in the larger...
I can't answer your question about ASME UG-125. I can try to explain the dual rating. The vessel is good for 250 psig from -20 to 300 F. At the colder temperatures from -20 to - 50 deg F there are decreased stress ratings for your SA516-70 material; thus the lower MAWP.
Your ammonia temperature...
There will not be an off the shelf solution. You will start evaporating various mixtures of ammonia / water through your batch process and eventually end up with 100% water at 212 deg F. I suppose there are systems that have condenser systems with them.
Why are you evaporating aqua ammonia to...
I'd say it has a 3 quarters pass [bigsmile]
Half the flow goes the full path the other half goes half the path [ponder]
All kidding aside you need to determine why such an arrangement would be desired.
I have seen quite a few profiles on LinkedIn with a long list of contract assignments especially for commissioning jobs.
I am usually impressed by these profiles (but then I am not HR)
I have used a functional resume because of a long career with one company. It has landed me my last 3 jobs...
MikeHalloran:
I was curious to know the reasons that functional resumes are red flags to HR people.
Regarding resume services: my experience is that they don't have a clue about engineering work. They all want accomplishments rather than tasks. As a design engineer the accomplishment is...
LittleInch:
I believe we are in agreement. I added the term "absolute" in parenthesis behind feet to make sure the conversion had been made from absolute pressures.
We are definitely in agreement about using absolute pressures throughout.
For me I always converted these to head and did the...
I am going to have to respectfully disagree with the last post. The relief in question is not being installed to protect the pump, it is being installed to protect the downstream piping from overpressure according to ASME requirements. Anything other than a relief valve, such as power monitoring...
Yes that is correct.
You have 14.696 + 1 = 15.696 psia
15.696 psia = 36.27 ft (absolute)
We are telling you, based on our experience, stop thinking of gauge pressures except to convert to absolute.
Utilize feet of liquid in calculating your pump hydraulic requirements
TRUST US [bigsmile]
Wow...that Mcinally example is certainly a source of confusion
Subtracting the gauge vacuum pressure from atmospheric is just a way to arrive at the absolute pressure at the liquid surface. Just stay in absolute units.
Expressing NPSHr in terms of absolute head is just convention.
Pressure or...
Unfortunately it is a matter of convention. Most NPSHr values are given in feet of liquid absolute. You can then choose whether to convert to gauge or absolute pressure.
Both suction head and discharge head SHOULD be expressed in feet liquid absolute.
The differential head is just that.
No...
Unfortunately there is not a simple conversion.
You are going to have to find and review your material balance around your column. Assume that this balance is the normal operating condition. Calculate your gas rate and liquid production rate and develop a "rule of thumb" ratio of gas to liquid...
I am missing something here. 1.8 x 500 psig = 900 psig (Not 1296 psig). How was the 1296 determined?
I am also not understanding the term "strength test pressure". There are pressure tests for systems according to ASME codes for process plant piping. What specific code are you utilizing? I...
That is an unusual flow measurement arrangement. The orifice is going to create a significant pressure drop in your suction line relative to the line friction loss. I would have selected some type of annubar arrangement; one of those that span the pipe diameter and have multiple holes...
Your sketch confirms what we already discussed.
The PSV capacity should match the maximum capacity of your pump.
The relieving temperature should be based on your analysis of your typical operating conditions
Good luck
