1-20 of 98 Search Results for

preheating

Follow your search
Access your saved searches in your account

Would you like to receive an alert when new items match your search?
Close Modal
Sort by
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001616
EISBN: 978-1-62708-229-7
... Abstract Severe pitting corrosion of a carbon steel tube was observed in the air preheater of a power plant, which runs on rice straw firing. Approximately 1450 tubes were removed from Stage 3 of the preheater (air inlet and flue gas outlet) due to corrosion and local bursting. Samples from...
Image
Published: 01 June 2019
Fig. 1 Schematic of the air preheater showing the different stages and the direction of air and flue gases (note the part of the outer shield is shown in open to reveal the pipes) More
Image
Published: 01 June 2019
Fig. 2 Cross-sectional schematic of the air preheater showing the (a) location of removed tubes and (b) general air flow and formation of dead zone at the rear end More
Image
Published: 01 June 2019
Fig. 3 Corroded carbon steel tubes removed from the air preheater in as-received condition. (a) Stage 2. (b) Stage 3 More
Image
Published: 01 January 2002
Fig. 21 Weld attaching the head to the shell of a steam preheater that cracked because of poor root penetration in original and first replacement joint designs. (a) and (b) Sections taken through the head-to-shell joint. Etched in hot 50% hydrochloric acid. Actual size. The section More
Image
Published: 01 June 2019
Fig. 1 Weld attaching the head to the shell of a steam preheater that cracked because of poor root penetration in original and first replacement joint designs. (a) and (b) Sections taken through the head-to-shell joint. Etched in hot 50% hydrochloric acid. Actual size. The section More
Image
Published: 01 December 1992
Fig. 2 Cutaway schematic of preheater/exchanger for chlorinated solvent combustion system. More
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.pulp.c0047529
EISBN: 978-1-62708-230-3
... Abstract A weld that attached the head to the shell of a preheater containing steam at 1.4 MPa (200 psi) and was used in the manufacture of paper cracked in service. The original joint contained a 6.4 by 50 mm backing ring that had been tack welded to the inside surface of the shell...
Series: ASM Failure Analysis Case Histories
Volume: 1
Publisher: ASM International
Published: 01 December 1992
DOI: 10.31399/asm.fach.v01.c9001046
EISBN: 978-1-62708-214-3
... Abstract The thin plates within a type 309 stainless steel chlorinated solvent combustion preheater/heat exchanger designed to process fumes from a solvent coating process showed severe corrosion within 6 months of service. Within a year corrosion had produced holes in the plates, allowing...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.conag.c0047392
EISBN: 978-1-62708-221-1
... metal arc welding; neither preheating nor postheating was specified. The filler metal was E70S-6 continuous consumable wire with a copper coating to protect it from atmospheric oxidation while on the reel. Analysis of the two castings revealed that the carbon content was higher than specified, ranging...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.marine.c9001210
EISBN: 978-1-62708-227-3
... was a construction steel of 60 to 75 kp/sq mm strength. Thick-walled parts of steels of such high strength must be preheated to approximately 200 deg C along the edges prior to welding to minimize the strong heat losses by the cold mass of the part. In the case under investigation this either was not done at all...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c0047632
EISBN: 978-1-62708-235-8
... boss on one side. After annealing, hot spinning, annealing a second time, and tack welding a port fitting, the assembly was torch preheated to 120 to 150 deg C (250 to 300 deg F). The port fitting was then welded in place. Final full heat treatment to the T62 temper was followed by machining, testing...
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.modes.c0091291
EISBN: 978-1-62708-234-1
... injected to control the scaling was added ahead of the preheater, where the boiler water still contained oxygen. As the chelate removed iron oxide, the O2 in the water continued to form more. Recommendations included moving the chelate addition to a point after the deaerator to stop the corrosion...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.bldgs.c9001611
EISBN: 978-1-62708-219-8
... was used to heat both base metals to at least 250 °F. This preheat temperature was verified by a melting-type temperature-indicating stick on the beam surface. All further heat input to the weld was from the FCAW welding process. The welding team had no knowledge of any postheat requirements following...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.petrol.c0047537
EISBN: 978-1-62708-228-0
... cellulosic electrodes. For high-risk girth welds, an increase in preheat and/or a reduction in the local stress by controlling lift height or depositing the hot pass locally before lifting may be required. Carbon equivalent Pipelines Weld defects Welding electrodes API X65 Hydrogen damage...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c0091009
EISBN: 978-1-62708-235-8
... as a result of stress-relief cracking. Very high residual stresses often result from welding thick sections of hardenable steels, even when preheating is employed. Quenched-and-tempered steels containing vanadium, as well as HSLA steels with a vanadium addition, have been shown to be susceptible...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c0047566
EISBN: 978-1-62708-235-8
... of using too large a welding rod and too much heat input, melting of the low-carbon steel handle, which diluted the austenitic stainless steel filler metal and formed martensitic steel in the weld zone. Because it was impractical to preheat and postheat the type 502 stainless steel cover plate, the low...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.process.c0047080
EISBN: 978-1-62708-235-8
... curvature, preheated, then solution treated, water quenched, and then aged for 8 to 10 h. Analysis (visual inspection, slow-bend testing, 65x macrographic analysis, macroetching, spectrographic analysis, hardness tests, microhardness tests, tension tests, and microscopic examination) supported...
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.usage.c0047545
EISBN: 978-1-62708-236-5
... was preheated to a temperature above which martensite would form. After completion, the weld was covered with an asbestos blanket, and heating was continued for 24 h. During the next 24 h, the temperature was slowly lowered. The result was a crack-free weld. Heat affected zone Martensite Post heating...