I don't believe temperatures in Ammonia Converter outlet line are high enough to initiate sensitization. This looks more like a high heat input related issue at the time of original welding.
In-service cracking issue is quite prevalent in stabilized austenitic steels. At our site we have also...
Thank you very much gentleman for your feedback. We will take this into account while finalizing our execution strategy. Appreciate if you can recommend some literature to study the subject in more detail.
Dear EdStainless,
Thank you very much for your feedback. While we agree with intended benefits of PWHT, we are struggling with the fact that owing to field constraints implementing PWHT as per intent will remain a challenge and there is a possibility that we may end up with multiple other...
Dear Experts,
I am reaching out to you to seek your expert advice regarding our 14” OD & 12.7 mm thk. Process Air Line (SS 321 H metallurgy) operating at 550 oC (1022oF) which we intend to replace due to multiple Stress Relaxation related cracking related leakages in the past. Root cause of...
Dear 0707,
Yes we did have a forced shutdown a month before this observation. Plant was shutdown in a controlled manner and within pre-defined IOWs for OPS team. Our hot face refractory is rich in Alumina (~ 94%) while our insulating side refractory is quite close to Resco RS9 grade. High...
Attaching the drawing and picture for review. https://files.engineering.com/getfile.aspx?folder=689ffb56-f9ba-4396-b444-89ce97dba0ea&file=Secondary_Reformer.pdf
Dear Experts,
Hope you are well. . I am writing this post to seek your expert opinion and guidance regarding a refractory issue faced recently at our site. Details are appended below.
We have a catalyst loaded vessel (secondary reformer) at our ammonia plant. This equipment is refractory lined...
Thank you very much gentlemen for your detailed feedbacks. As ammonia fertilizer manufacturing plant operators we have faced Ammonia SCC related issues sporadically. RCA for most of the issues observed at our site have pointed to non-compliances to required fabrication requirements at the time...
Dear Experts,
We are getting a new Ammonia Storage Vessel fabricated. Given below are major equipment design details
Material (nozzles/ shell & heads): SA-333 GR.6 / SA-516 GR.60
Design Pressure: 30 kg/cm2
Design Temperature: -20/70 OC
Material thickness: 32 mm
As per equipment manufacturing...
Dear Experts,
Hope you are well. We have a double walled Ammonia Storage Tank at our site with below mentioned key specifications:
Material: A-516 Gr 60
Height: 16 meters
Inner Tank ID: 26 meters
Operating Temperature: -33oC
Capacity: 7,350 m3
Design Code: API 620
Commissioning Year: 2010
No...
Dear Experts,
Hope you are well. We have a double walled Ammonia Storage Tank at our site with below mentioned key specifications:
Material: A-516 Gr 60
Height: 16 meters
Inner Tank ID: 26 meters
Operating Temperature: -33oC
Capacity: 7,350 m3
Design Code: API 620
Commissioning Year: 2010
No...
Just an update on subject issue, over the course of this week we have been conducting in-service PAUT of butt weld joints in said piping. Weld joints have been carefully selected in immediate vicinity of both leakages and areas of relatively higher flowrate than running pipe length. So far out...
Dear Morten,
Attached is a close up of elbow cut at its weld joint area. Point of leakage in the elbow is 9 o clock position. Most of the weld joint on elbow was removed during welding joint removal however as you can see the HAZ area at both top and bottoms side is eroded. Depth and...
Dear Experts,
Got our process engineer to model the flow rate at different zones of the piping and as per flow simulation velocities are not higher than licenser recommended flowrate at different pipe sizes. I have attached the flow rate simulation model and licenser recommended max fluid...
Dear Andersen,
Thank you for your feedback. We are struggling with why the HAZ is being attacked and that too of only upstream weld joint. Additionally with passivation layer intact, shouldn't corrosion become insignificant? Or is there any reason to believe that passivation layer can not form...
Dear Experts,
Over the last 1 month we have observed 02 leakages from our CO2 removal unit piping. Request your expert advice on what are the likely cause(s) for these leakages and what can be done to prevent any further leakages. Given below are brief details of the process and respective...
Dear All,
We are using plug globe valves as isolating valves on our ammonia circulation pumps. Temperature of service varies between zero degree C to ambient temperature of 25 degree C. We have recently been observing leakages from these valves glands. The valves were installed about 30 years...
Hi,
Our company is trying to setup a heat exchanger retubing facility at our site. Over the next few years we intend to re-tube heat exchangers with tubes in the size range of 1/2" to 1". I am developing a technical SOW for bidding purposes for a Electrically operated Hydraulic Tube Puller...
