The point is that how he can get a constant head at 0 flow unless there is a overhead tank to provide a constant head at all flows.
If you have two pumps in series without any static head then system resistance curve should have 0 head at 0 flow.
I am not in this specialized field.
But this site may help:
http://www.lieberman-eng.com/personnel.htm
Especially "PROCESS DESIGN FOR RELIABLE OPERATIONS".
Good Luck!
Since the valve was tested repeatedly at comparatively high pressures(max allowable 830 psi, first test pressure 1580 psi), it is possible that the ball had yielded at such high pressures. With repeated loadings, the ball might have cracked due to low cycle fatigue (LCF).
I could not locate the tube-side velocity limit in TEMA. This may be because TEMA is a manufacturing standard rather than a design standard(even though many clauses in TEMA pertain to design, e.g., shell diameters, etc.).
However, Heat Exchange Institute (HEI) does provide limits for tube side...
Too many curves and legends. It will be helpful to show only a) Single pump characteristics b) combined pump characteristics. c) system resistance curve.
You need to see the stress analysis results and also see the definition of 'stress ratio' in 323.2.2 b). Using the various stress criteria available in the stress analysis results and material allowable stress, you can find the stress ratio.
In my earlier post, I considered linear region only.
A simplified model should include the plastic region also till rupture.
A simple method will be to take the stress-strain diagram to the breaking point and numerically integrate it for the area beneath the curve. Multiplication of this with...
A simplified method could be the the use of strain energy.
It assumes that you know the kinetic energy of the impacting body.
The kinetic energy will be reduced by consumption in the strain energy U.
The stress could be the breaking stress of the material in question.
If you have flow data and thermal properties of product/reagent, you can conduct a heat and mass balance study to determine the steam flow rate. This assumes that the main task of steam is for heating of product/reagent.
Centrifugal pump is a dynamic machine where there is no definite flow or head.
The combined Q-H curve is to be obtained by adding the heads generated by two pumps at any particular flow as @LittleInch said.
Both pumps will deliver the same flow, which is determined by the combined Q-H curve...
The philosophy of safety valve setting should be to protect the piping and the downstream equipment. Irrespective of the achieved pressure at the downstream end, if the piping and equipment downstream can sustain a design pressure of say, 7 or 8 bar(g), then the safety valve set pressure can be...
