Studies on the metallographic inspection of HK‐40 reformer tubes

1984 ◽  
Vol 31 (3) ◽  
pp. 9-15
Author(s):  
K.M. Verma ◽  
S.C. Verma ◽  
A.K. Sinha
Keyword(s):  
Metallographic Inspection ◽  
Reformer Tubes

THERMALLOY 63W

Alloy Digest ◽  
1978 ◽  
Vol 27 (6) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Iron Alloy ◽  
Heat Treating ◽  
Centrifugally Cast ◽  
Nickel Chromium ◽  
Reformer Tubes ◽  
Temperature Applications

Abstract THERMALLOY 63W is a cast nickel-chromium-tungsten-iron alloy produced for service at temperature up to 1900 F. Centrifugally cast reformer tubes comprise one of its high-temperature applications. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: SS-352. Producer or source: Abex Corporation, Engineered Products Division.

An EBSD Study on Orientation Effects during Recrystallization of Coarse-Grained Niobium

2004 ◽  
Vol 467-470 ◽  
pp. 519-524 ◽  
Author(s):  
Hugo Ricardo Zschommler Sandim ◽  
Dierk Raabe
Keyword(s):  
Longitudinal Section ◽  
Primary Recrystallization ◽  
Coarse Grained ◽  
Subgrain Structure ◽  
Electron Backscattered Diffraction ◽  
Subgrain Growth ◽  
Metallographic Inspection ◽  
Cold Rolled ◽  
Cold Worked ◽  
Viable Mechanism

The recrystallization behavior of coarse-grained niobium depends on the nature of its deformation microstructure. In this regard, a longitudinal section of a high-purity coarse-grained niobium ingot was cold rolled to a thickness reduction of 96% followed by annealing in vacuum at 800°C for 1 h. Metallographic inspection in cold-rolled and annealed specimens was carried out in a field emission gun scanning electron microscope (FEG-SEM). Microtexture was determined by electron-backscattered diffraction (EBSD) coupled to the FEG-SEM. The use this technique has evidenced details of the boundary character and subgrain structure found in partially recrystallized regions. The early stages of primary recrystallization are associated to the presence of high-angle lamellar boundaries found in the cold-worked state. Abnormal subgrain growth has been evidenced as a viable mechanism for nucleation of recrystallization.

scholarly journals Creep Failure of Reformer Tubes in a Petrochemical Plant

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1026 ◽  
Author(s):  
Abbas Bahrami ◽  
Peyman Taheri
Keyword(s):  
High Temperature ◽  
Void Coalescence ◽  
Petrochemical Plant ◽  
Creep Failure ◽  
X Ray ◽  
Carbide Phases ◽  
Electron Microscopes ◽  
Reformer Tubes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

This paper investigates a failure in HP-Mod radiant tubes in a petrochemical plant. Tubes fail after 90,000 h of working at 950 °C. Observed failure is in the form of excessive bulging and longitudinal cracking in reformer tubes. Cracks are also largely branched. The microstructure of service-exposed tubes was evaluated using optical and scanning electron microscopes (SEM). Energy-dispersive X-ray spectroscopy (EDS) was used to analyze and characterize different phases in the microstructure. The results of this study showed that carbides are coarsened at both the inner and the outer surface due to the long exposure to a carburizing environment. Metallography examinations also revealed that there are many creep voids that are nucleated on carbide phases and scattered in between dendrites. Cracks appeared to form as a result of creep void coalescence. Failure is therefore attributed to creep due to a long exposure to a high temperature.

Failure analysis of catalytic steam reformer tubes

2005 ◽  
Vol 52 (6) ◽  
pp. 337-344 ◽  
Author(s):  
H.M. Tawancy ◽  
A. Ul‐Hamid ◽  
A.I. Mohammed ◽  
N.M. Abbas
Keyword(s):  
Failure Analysis ◽  
Steam Reformer ◽  
Reformer Tubes

Creep embrittlement in aged HP-Mod alloy reformer tubes

2019 ◽  
Vol 100 ◽  
pp. 147-165 ◽  
Author(s):  
Kiran Rampat ◽  
Chris Maharaj
Keyword(s):  
Reformer Tubes

Damage Analysis of Service Exposed Reformer Tubes in Petrochemical Industries

2014 ◽  
Vol 33 (3) ◽  
pp. 201-216 ◽  
Author(s):  
A. Raj ◽  
B. Goswami ◽  
S.B. Kumar ◽  
G. Krishna ◽  
N. Roy ◽  
...  
Keyword(s):  
Hot Spot ◽  
Stress Rupture ◽  
Outer Wall ◽  
Nickel Catalysts ◽  
Time Frame ◽  
Life Assessment ◽  
Damage Analysis ◽  
Diameter Increment ◽  
Accelerated Creep ◽  
Reformer Tubes

AbstractAccelerated creep or stress rupture data is used for remaining life assessment for life management studies of elevated temperature components, e.g. for reformer tubes where packed nickel catalysts are used for synthesis of hydrogen, ammonia etc. This research has become a regular task because of large range of time for failure (3 to 15 years) compared to designed life (11.4 years or 100,000 hours) and huge loss associated to damage, production and safety hazards. Utilization of appropriate inspection during plant shut down has been strategic short term life assessment. Tests have been typically done by high temperature mechanical properties, microstructure analysis and accelerated creep. Inspection of micro-cracks, hot spot formation, carburization/metal dusting for inner wall and oxidation, tube diameter increment for outer wall inspection have been traditional symptoms of expiry of tubes after service exposure. Aim of this review has been to study damage analysis of reformer tube in response to so wide time frame for failures and accidents involved, even after stipulation of designed time schedules.

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