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boiler tubes

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Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001480
EISBN: 978-1-62708-229-7
... Abstract One tube in a watertube boiler developed leakage from a perforation. The external surface was covered with a dark deposit indicative of local fusion. Perforation resulted from the development of a crack from the internal surface. Microscopic examination revealed extensive intergranular...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001176
EISBN: 978-1-62708-229-7
... Abstract A backwell tube situated in the combustion chamber of a 100 atm boiler, which had been in service for many years, failed. The temperature of the saturated steam was about 300 deg C. Two pipe sections with attacked areas in the circumferential welding joint were examined for cause...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001482
EISBN: 978-1-62708-229-7
... Abstract Penetration by molten copper occurred in the economizer of a large water-tube boiler. A cross section through a weld and the crack in the tube revealed a crack was an intergranular fissure. Small fissures of the same type also extended from its flanks. The main fissure was filled...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.modes.c0048289
EISBN: 978-1-62708-234-1
... Abstract The center portions of two adjacent low-carbon steel boiler tubes (made to ASME SA-192 specifications) ruptured during a start-up period after seven months in service. It was indicated by reports that there had been sufficient water in the boiler two hours before start-up...
Series: ASM Failure Analysis Case Histories
Volume: 2
Publisher: ASM International
Published: 01 December 1993
DOI: 10.31399/asm.fach.v02.c9001340
EISBN: 978-1-62708-215-0
... Abstract Two identical “D” tube package boilers, installed at separate plants, experienced a number of tube ruptures after relatively short operating times. The tubes, which are joined by membranes, experienced localized bulging and circumferential cracking along the fireside crown as a result...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.marine.c0048350
EISBN: 978-1-62708-227-3
... Abstract Tubes in a marine boiler on a new ship failed after brief service lives. Circumferential brittle cracking was found to occur in the carbon-molybdenum steel tubes near the points where the tubes were attached to the steam drum. Fatigue striations were revealed by examination of fracture...
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Published: 01 January 2002
Fig. 9 Microstructures of specimens from carbon steel boiler tubes subjected to prolonged overheating below Ac 1 . (a) Voids (black) in grain boundaries and spheroidization (light, globular), both of which are characteristic of tertiary creep. 250×. (b) Intergranular separation adjacent More
Image
Published: 01 January 2002
Fig. 10 Typical microstructures of 0.18% C steel boiler tubes that ruptured as a result of rapid overheating. (a) Elongated grains near tensile rupture resulting from rapid overheating below the recrystallization temperature. (b) Mixed structure near rupture resulting from rapid overheating More
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Published: 01 January 2002
Fig. 12 Plots of scale thickness versus temperature for two sizes of boiler tubes and two values of heat flux. (a) and (b) The effect of scale thickness on the temperature gradient across the scale. (c) and (d) The effect of scale thickness on the temperature of the metal at the outer surface More
Image
Published: 15 January 2021
Fig. 19 Oxygen pitting along the outside-diameter surface of boiler tubes from a fire-tube boiler. (a) Through-wall pitting due to oxygen pitting. (b) Oxygen pitting had penetrated approximately 80% of the boiler tube wall thickness on this sample. More
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Published: 15 January 2021
Fig. 9 (a) Short-term and (b) long-term overheating of boiler tubes. Long-term overheating usually is caused by creep as the microstructure of the material degrades at temperature over time. Grains do not deform, but voids develop at grain-boundary junctions and grow and coalesce over time More
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.modes.c0091291
EISBN: 978-1-62708-234-1
... Abstract Carbon steel tubes from a boiler feedwater heater feeding a deaerator were treated to control scale formation, but the treatment instead produced more iron oxide. The additional iron oxide reduced the tubing to a totally corroded condition. Investigation showed that the chelate...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001709
EISBN: 978-1-62708-229-7
... Abstract Several waterwall tubes in a power station boiler failed after ten years of service. The boiler is a suspension type equipped with 30 IK boxes where retractable soot blowers are inserted to clean the inside of the boiler using high-pressure steam. The tubes, which operate at 693 deg F...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001479
EISBN: 978-1-62708-229-7
... Abstract Several ruptures took place in the front wall tubes of a water tube boiler. Some rupture samples showed ductile failure while others showed brittle failure. Specimens taken from the rupture where a thick edge had been produced, i.e., with little evidence of prior plastic deformation...
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001834
EISBN: 978-1-62708-241-9
... to high temperature corrosive flux accelerated the corrosion on the outer wall. Microstructure degradation and the corrosion characteristics observed indicate that the tubes failed primarily because of overheating, which is confirmed by calculations. boiler tubes stress rupture wall thinning low...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c9001194
EISBN: 978-1-62708-235-8
... Abstract A seamless hot-drawn boiler tube NW 300 of 318 mm OD and 9 mm wall thickness made of steel 15Mo3 was bent with sand filling after preheating allegedly to 1000 deg C. In the process it had cracked repeatedly in the drawn fiber. The composition corresponded to specifications...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001569
EISBN: 978-1-62708-229-7
... of other units. Boilers Economizers Superheaters Tubing Steel tube Corrosion fatigue Transgranular fracture Fatigue fracture Introduction Understanding the characteristic causes of fatigue failures should help to identify areas of the boiler that may be more likely to fail by fatigue...
Series: ASM Failure Analysis Case Histories
Volume: 2
Publisher: ASM International
Published: 01 December 1993
DOI: 10.31399/asm.fach.v02.c9001739
EISBN: 978-1-62708-215-0
... Abstract The rear wall tube section of a boiler that had been in service for approximately 38 years was removed and examined. Visual examination of the tube revealed a small bulge with a through-wall crack. Metallography showed that the microstructure of the bulged area consisted of a few...
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001791
EISBN: 978-1-62708-241-9
... temperatures. The combined effect of pitting, incrustations, and phase transformations caused the pipe to rupture. boiler tube fracture corrosion pits salt incrustation carbon steel thermal fatigue striations dimples microstructural analysis plastic strain A192 (carbon steel) UNS K01201...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c9001433
EISBN: 978-1-62708-235-8
... Abstract On attempting to manipulate or bend a boiler tube some 22 ft. long, sudden failure occurred at what appeared to be a butt weld in the tube. Externally, the weld reinforcement had been ground flush and the entire tube surface painted. Internally, the appearance and width of the heated...