We are modifying old existing 2.25 Cr 1 Mo A335 P22 (Desuperheater ) piping to incorporate a new type of desuperheater. The new piping material comply with Jfactor <100 requirement. We are not sure whether the old material complies.
My query is can we determine how much extend temper...
Have a query.
What is the DBTT-Ductile Brittle transition temperature for 2 1/4 Cr-1 Mo -P22/F22 chrome moly material?
Is there a formula for calculating this DBTT?
Is this DBTT valve fixed for all 2 1/4 Cr-1 Mo -P22/F22 chrome moly material?
Is there a chart available in ASTM / other standards?
DV
P22 Piping materials Tempering process carried out at typically 740degC. Whether PWHT holding temperature for P22 material can be above tempering temperature?
In the below thread there is a comment
The code committee, for various reasons, changed the factor against ultimate from 4 to 3.5 starting with the 1999 Addenda. Factors against yield, time dependent, and compressive did not change.
what are the current factors against yield,time dependent and...
For SA-106 Grade B pipe ,After 375 deg C the max allowable stress values are time dependant. Notes T1 & G10 ASME sec II Part D
NOTES — TIME-DEPENDENT PROPERTIES
T1 Allowable stresses for temperatures of 370°C and above are values obtained from time-dependent properties.
G10 Upon prolonged...
Hi
Derating of process piping
I want to know whether derating can be applied in the below scenario.
This is a modification of existing syngas line which is 15 years old. The current piping is designed to 550 deg C and pressure to 52 bar
But there is an alarm in the system at 285 deg C.
My...
In what circumstances design temperature of a piping system can be changed?
-In a operating plant ,the operating temperature of a particular pipe system (where alteration/Modification required) is max 300 deg C,above which there will be alarm/Trip.But the piping is designed to a higher...
I have a query regarding Isolation valves in syngas service.
Current Valve size is 16"(400NB)class 600
Temperature 293 deg C
Pressure 35 Bar
Current Valve is a GATE VALVE.
What are the pros and cons of using a BALL VAlVE in the place of above GATE VALVE.
DV
Can flanged valve be used instead of welded valve.
Process : Water gas shift reaction
Existing design
-welded 16"(400NB) Ball (HV )control valve
-Temperature 270 deg C
-Pressure 35 Bar
-process gas line
-Material is P11 Stress relived line
Proposed change
-Replace existing welding valve with...
Can flanged valve be used instead of welded valve.
Process : Water gas shift reaction
Existing design
-welded 16"(400NB) Ball (HV )control valve
-Temperature 270 deg C
-Pressure 35 Bar
-process gas line
-Material is P11 Stress relived line
Proposed change
-Replace existing welding valve with...
Cutting 4 lifting lug during installation due to interference with structural beam.
1. Does it affect the integrity of vessel?
2.How much protrusion should be kept after cutting?
3.Which method of cutting(oxy cutting allowed?) permitted? What precaution to be taken.
DV
QW-406 PREHEAT ASME IX
QW-406.1 states A decrease of more than 100°F (55°C) in the preheat temperature qualified. The minimum temperature for welding shall be specified in the WPS.
What does the "decrease of more than 100°F (55°C)" mean?
ASME IX Table QW-253 this is an essential variable.
Does...
What Qualification/certification required for WPS review and approval for a ASME HX fabrication?
Is this specified in ASME IX?
If the WPS not checked/approved by a qualified/certified Welding expert correctly ,how can the risk of weld failure avoided?
DV
Who can review and approve Welding procedure specification for a Pressure vessel fabrication Project?
What all qualification is required?
PQR approved and stamped by Lloyds Register inspector,is this recognised internationally?
Thanks,
DV
For NEN type Heat exchanger as per client specification Shell side PWHT is Mandatory-Due to service requirements.
Shell SA516-GA70 Thk 38mm, I.5 meter dia,10 meter long
Tubes SA-179 Dia 19.05, 2.11mm thk,9150 mm long(approx 3000 tubes)
Tube sheets(fixed): SA765 Gr.II
Which is the preferred PWHT...
QW193.1.1 Procedure qualification TTS welding mentions -there should not have any evidence of burning through the tube wall-for the acceptance of TTS welding?
What are the reasons for the above? Is there an integrity issue that can occur in the life of heat exchanger?
If the burning through...
thread391-504505
The response from a specialist steam surface condenser vendor with regards to tender (RFP) for design &fabrication of Steam Surface Condenser
1"We will not provide thermal & mechanical calculations.These are proprietary documents and we do not submit to client." Is this...
A modification is suggested by operations to modify a High Pressure Steam piping to install a new type inline type desuperheater.
Operating pressure 870 PSIG and Temperature 950 degree F.The plant is 20 years old.
To do this modification,what are the critical things to consider?
DO we need to...
