Skip Nav Destination
Close Modal
Search Results for
circumferential wear marks
Update search
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
NARROW
Format
Topics
Book Series
Date
Availability
1-20 of 72 Search Results for
circumferential wear marks
Follow your search
Access your saved searches in your account
Would you like to receive an alert when new items match your search?
1
Sort by
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001846
EISBN: 978-1-62708-241-9
... chromium steel circumferential wear marks peel pits heat tinting fatigue striations SEM imaging fatigue strength 42CrMo (chromium-molybdenum alloy steel) 38CrMoAl (chromium-molybdenum-aluminum alloy steel) Background A locomotive turbocharger main shaft and a bearing sleeve assembled...
Abstract
The main shaft in a locomotive turbocharger fractured along with an associated bearing sleeve. Visual and fractographic examination revealed that the shaft fractured at a sharp-edged groove between two journals of different cross-sectional area. The dominant failure mechanism was low-cycle rotation-bending fatigue. The bearing sleeve failed as a result of abrasive and adhesive wear. Detailed metallurgical analysis indicated that the sleeve and its respective journal had been subjected to abnormally high temperatures, increasing the amount of friction between the sleeve, bearing bush, and journal surface. The excessive heat also softened the induction-hardened case on the journal surface, decreasing its fatigue strength. Fatigue crack initiation occurred at the root fillet of the groove because of stress concentration.
Image
in Failure Investigation of a Locomotive Turbocharger Main Shaft and Bearing Sleeve
> Handbook of Case Histories in Failure Analysis
Published: 01 December 2019
Fig. 3 Surface damage morphology of main shaft ( a ) showing serious circumferential wear marks and ( b ) showing serious peel pits
More
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001847
EISBN: 978-1-62708-241-9
... surface of the bearing sleeve and brown oxidation tint is exhibited on the cylinder surface. Fig. 1 Failed sleeve and a new sleeve: ( a ) failed sleeve and ( b ) new sleeve Densely distributed deep circumferential wear marks ( Fig. 1a ) are present on the external surface in the left region...
Abstract
An investigation was conducted to determine what caused a bearing sleeve in a locomotive turbocharger to fail. The sleeve, which is made of nitrided 38CrMoAl steel, fractured at the transition fillet between the cylinder and plate. Visual examination revealed significant wear on the external surface of the cylinder, with multiple origin fatigue fracture appearing to be the dominant fracture mechanism. Metallurgical examination indicated that the nitrided layer was not as deep as it was supposed to be and had worn away on the outer surface of the sleeve, exposing the soft matrix underneath. This led to further wear and an increase in friction between the sleeve and bearing bush. Fatigue crack initiation occurred at the root fillet because of stress concentration and large frictional forces. Insufficient nitriding depth facilitated the propagation of fatigue cracks.
Book Chapter
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.aero.c0046222
EISBN: 978-1-62708-217-4
... in inches. (b) Longitudinal score mark (region A) and circumferential scratches (arrow B) on shank that had been peened over. A galled area (arrow C) is also visible. At every overhaul, the spindles were fluorescent-magnetic-particle inspected, and the surface was carefully examined for evidence...
Abstract
The spindle of a helicopter-rotor blade fractured after 7383 h of flight service. At every overhaul (the spindle that failed was overhauled six times and reworked twice), any spindle that showed wear was reworked by grinding the shank to 0.1 mm (0.004 in.) under the finished diam. The spindle was then shot peened with S170 shot to an Almen intensity of 0.010 to 0.012 A. Following shot peening, the shank was nickel sulfamate plated to 0.05 mm (0.002 in.) over the finished diam, ground to finished size, and cadmium plated. Visual and stereomicroscopic exam showed faint grinding marks and circumferential grooves on the surface near the fillet at the junction of the shank and fork, which should have been peened over and covered with peening dimples. Evidence found supports the conclusions that the spindle failed in fatigue that originated near the junction of the shank and fork. The nonuniformity of the shot-peened effect on the shank and fillet portions of the spindle resulted from incomplete peeing. The fracture was of the low-stress high-cycle type, initiated by stresses well below the gross yield strength and propagated by thousands of load cycles. No recommendations were made.
Series: ASM Failure Analysis Case Histories
Volume: 3
Publisher: ASM International
Published: 01 December 2019
DOI: 10.31399/asm.fach.v03.c9001849
EISBN: 978-1-62708-241-9
... marks (beach marks) Optical examination of the surface (roll surface) of the fragment revealed a sliding wear pattern and a characteristic network of multiple interconnecting cracks ( Fig. 4 ). This surface crack pattern might be attributed to the formation of firecracks or thermal cracks (known...
Abstract
Spalled fragments from the work rolls of a steel bar straightening machine were received for failure analysis. Visual inspection coupled with optical and scanning electron microscopy were used as the principal analytical techniques for the investigation. Fractographic analysis revealed the presence of a characteristic fatigue crack propagation pattern (beach marks) and radial chevron marks indicating the occurrence of final overload through a brittle intergranular fracture. The collected evidence suggests that surface-initiated cracks propagated by fatigue led to spalling, resulting in severe work roll damage as well as machine downtime and increased maintenance costs.
Series: ASM Failure Analysis Case Histories
Volume: 1
Publisher: ASM International
Published: 01 December 1992
DOI: 10.31399/asm.fach.v01.c9001115
EISBN: 978-1-62708-214-3
... The failure selected for analysis was a circumferential fracture of the tubing in a connection ( Fig. 1 ). Reported to be a Hydril CS connection, the pin end parted near the last threads. The external box surface exhibited mechanical damage marks from the fishing operation. Except for these marks, no signs...
Abstract
During a work over of an oil well, the 9% Ni steel production tubing parted three times as it was being pulled from the well. The tubing had performed satisfactorily for more than 30 years in the well A representative failure, a circumferential fracture in a connection, was analyzed. Reported to be a hydril CS connection, the pin end parted near the last threads. The external surface exhibited mechanical damage marks from the fishing operation. No signs of external corrosion or damage were detected. Visual surface examination revealed shear lips at the outside pipe, indicating that the fracture initiated at the inside surface and grew across the wall. Longitudinal cross sections revealed heavy corrosion damage to the inside pipe surface. Metallographic examination indicated that the tubing failed as a result of severe weakening from internal corrosion. Gray-colored corrosion deposits, which penetrated the pipe throughout the grain boundaries of the material and concentrated in the matrix in a layer near the inside surface of the pipe, were observed. The presence of H2S in the produced fluids and the appearance of the gray deposit indicated that the tube suffered H2S corrosion. Chemical analysis of the base metal and corrosion deposits did not detect iron or nickel sulfides, however Replacement of the remaining pipe strings according to a scheduled program was recommended. Because 9% Ni steel was not available, 13% Cr martensitic stainless steel was recommended as a replacement.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.usage.c9001597
EISBN: 978-1-62708-236-5
... diagonal and then circumferential near each end of the journal. Circumferential abrasive wear patterns were present over the entire journal surface, with more severe areas located along the center and near an area of spalling along the cracks ( Fig. 3 ). Several areas on the surface exhibited small...
Abstract
This case study involves two continuously cast steel crankshaft failures. Three parties performed their own failure analyses: (1) the engine manufacturer responsible for component design, specification, and application; (2) the steel supplier and forging supplier responsible for making the steel, forging the shape, and preliminary heat treatment; and (3) a supplier that provided induction hardening, finish machining, and inspection. An independent engineering firm was subsequently involved, but because each party had its own agenda, there was no agreement on the metallurgical source of the failure and thus no continued analysis to pin down and eliminate the root cause.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.chem.c9001713
EISBN: 978-1-62708-220-4
.... Several radial marks are also visible on the surface of the seal (near arrows). Fig. 11 Optical micrograph of the replicated surface of the inboard seal showing a radial groove (horizontal) and a circumferential groove (vertical). The scale bar is 200 µm in length. The depth...
Abstract
On 21 April 1995, the contents of a large blender (6 cu m) reacted and caused an explosion that killed and injured a number of workers at a plant in Lodi, NJ. A mixture of sodium hydrosulfite and aluminum powder was being mixed at the time of the accident. This report focuses on evaluations of the blender to determine if material or mechanical failures were the cause of the accident. The results indicate that the mixing vessel was metallurgically sound and did not contribute to the initiation of the failure. However, the vessel was not designed for mixing chemicals that must be isolated from water and excessive heat. Water leaking into the vessel through a graphite seal may have initiated the reactions that caused the accident.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.usage.c0046242
EISBN: 978-1-62708-236-5
... into the gear teeth. Severe wear and broken teeth were also observed. A crack was found that apparently started in the keyway and continued circumferentially around the coupling (Details A and B, Fig. 1 ). Spectrographic analysis of the coupling material revealed that it was made of a chromium-molybdenum...
Abstract
An integral coupling and gear (Cr-Mo steel), used on a turbine-driven main boiler-feed pump, was removed from service after one year of operation because of excessive vibration. Spectrographic analysis and metallographic examination revealed the fact that gritty material in the gear teeth (found at visual inspection) was composed of the same material as the metal in the coupling. Beach marks and evidence of cold work, typical of fatigue failure, were found on the fracture surface. Chips remaining in the analysis cut were difficult to remove, indicating a strong magnetic field in the part. Evidence found supports the conclusions that failure of the coupling was by fatigue and that incomplete demagnetization of the coupling following magnetic-particle inspection caused retention of metal chips in the roots of the teeth. Improper lubrication caused gear teeth to overheat and spall, producing chips that eventually overstressed the gear, causing failure. Because the oil circulation system was not operating properly, metal chips were not removed from the coupling. Recommendations included checking the replacement coupling for residual magnetism and changing or filtering the pump oil to remove any debris.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.pulp.c0048804
EISBN: 978-1-62708-230-3
... surface were found to exhibit chevron marks typical of fatigue or raised points or tears pointing in the direction of the probable origin of failure. The characteristics of the thinwall cast iron structures like the variation in composition due to pouring from multiple ladles, variation in solidification...
Abstract
Several cases of failures in gray cast iron paper machine dryer rolls were evaluated. The rolls were found have ground outer cylindrical surfaces on which the paper web is dried. They were found to rotate about their longitudinal axes at speeds from 50 to 250 rpm while containing saturated steam from 35 to 380 kPa. Failures were found to occur in the shell body, in a head near a hand hole or a manhole opening, or in a head near the journal-to-head interface. A cleavage fracture was revealed by scanning electron microscopy regardless of the driving stress for failure. Fracture surface were found to exhibit chevron marks typical of fatigue or raised points or tears pointing in the direction of the probable origin of failure. The characteristics of the thinwall cast iron structures like the variation in composition due to pouring from multiple ladles, variation in solidification rates, and variation in tensile strength to be noted during inspection were described.
Series: ASM Failure Analysis Case Histories
Volume: 1
Publisher: ASM International
Published: 01 December 1992
DOI: 10.31399/asm.fach.v01.c9001044
EISBN: 978-1-62708-214-3
... Both lots of tubing were visually examined and found to contain longitudinal and circumferential external cracks and to be heavily stained with obvious liquid runoff and drip marks. On the tube samples examined, the majority of the longitudinal cracks ran along the top and bottom of the tubes; most...
Abstract
Inhibited admiralty brass (UNS C44300) condenser tubes used in a natural-gas-fired cogeneration plant failed during testing. Two samples, one from a leaking tube and the other from an on leaking tube, were examined. Chemical analyses were conducted on the tubes and corrosion deposits. Stress-corrosion cracking was shown to have caused the failure. The most probable corrosive was ammonia or an ammonium compound in the presence of oxygen and water. All of the tubes were replaced.
Series: ASM Handbook
Volume: 11A
Publisher: ASM International
Published: 30 August 2021
DOI: 10.31399/asm.hb.v11A.a0006806
EISBN: 978-1-62708-329-4
..., but axial grooves are easier to make. Fig. 3 Groove arrangements in sliding bearings Apart from axial, circumferential, and spiral grooves, the surfaces of bearings may be textured to improve wear resistance and reduce energy losses by reducing friction. In recent years, improving or modifying...
Abstract
A mechanical part, which supports the moving part, is termed a mechanical bearing and can be classified into rolling (ball or roller) bearings and sliding bearings. This article discusses the failures of sliding bearings. It first describes the geometry of sliding bearings, next provides an overview of bearing materials, and then presents the various lubrication mechanisms: hydrostatic, hydrodynamic, boundary lubrication, elastohydrodynamic, and squeeze-film lubrication. The article describes the effect of debris and contaminant particles in bearings. The steps involved in failure analysis of sliding bearings are also covered. Finally, the article discusses wear-damage mechanisms from the standpoint of bearing design.
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0001808
EISBN: 978-1-62708-180-1
... that will not remove or obliterate any rust, oxidation, burnishing marks, or other pertinent evidence. Surfaces of all areas that may have been involved in or may have contributed to the failure should be examined, noting scuff marks, burnished areas, abnormal surface blemishes, and wear. These marks should...
Abstract
This article discusses failures in shafts such as connecting rods, which translate rotary motion to linear motion, and in piston rods, which translate the action of fluid power to linear motion. It describes the process of examining a failed shaft to guide the direction of failure investigation and corrective action. Fatigue failures in shafts, such as bending fatigue, torsional fatigue, contact fatigue, and axial fatigue, are reviewed. The article provides information on the brittle fracture, ductile fracture, distortion, and corrosion of shafts. Abrasive wear and adhesive wear of metal parts are also discussed. The article concludes with a discussion on the influence of metallurgical factors and fabrication practices on the fatigue properties of materials, as well as the effects of surface coatings.
Series: ASM Handbook
Volume: 11A
Publisher: ASM International
Published: 30 August 2021
DOI: 10.31399/asm.hb.v11A.a0006810
EISBN: 978-1-62708-329-4
..., or other pertinent evidence. Surfaces of all areas that may have been involved in or may have contributed to the failure should be examined, noting scuff marks, burnished areas, abnormal surface blemishes, corrosion, and wear. These marks should be associated with some abnormal service condition...
Abstract
In addition to failures in shafts, this article discusses failures in connecting rods, which translate rotary motion to linear motion (and conversely), and in piston rods, which translate the action of fluid power to linear motion. It begins by discussing the origins of fracture. Next, the article describes the background information about the shaft used for examination. Then, it focuses on various failures in shafts, namely bending fatigue, torsional fatigue, axial fatigue, contact fatigue, wear, brittle fracture, and ductile fracture. Further, the article discusses the effects of distortion and corrosion on shafts. Finally, it discusses the types of stress raisers and the influence of changes in shaft diameter.
Series: ASM Failure Analysis Case Histories
Volume: 2
Publisher: ASM International
Published: 01 December 1993
DOI: 10.31399/asm.fach.v02.c9001370
EISBN: 978-1-62708-215-0
... ranging from 31.4 to 34.7 mm (1.2 to 1.4 in.), indicating about 3.5 mm (0.14 in.) of mechanical wear of the shaft in the threaded portion of the sleeve nut. A 3 mm (0.12 in.) deep circumferential groove was visible 45 mm (1.7 in.) from the fracture surface. Fig. 1 The drive-end side of the shaft...
Abstract
A service water pump in a nuclear reactor failed when its shaft gave way. The fracture originated in the threaded portion of the sleeve nut on the drive-end side of the shaft. Results of the failure analysis showed that the cracking initiated at the thread root as a result of corrosion fatigue. Crack propagation occurred either by corrosion or mechanical fatigue. Evidence was found indicating high rotary bending stresses on the shaft during operation. The nonstandard composition of the En 8 steel used in the shaft and irregular maintenance reduced the life of the shaft. Recommendations included use of a case-hardened En 8 steel with the correct composition and regular maintenance of the pump.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.mech.c9001485
EISBN: 978-1-62708-225-9
... into heavy contact with one of the flanges of the inner race, resulting in smearing and wear to the extent shown by those marked X and Z. Although, in these two rollers, the zone of final fracture was located adjacent to the smeared end, this was not true of all the cracked rollers, since as shown by roller...
Abstract
Factors which may lead to premature roller bearing failure in service include incorrect fitting, excessive pre-load during installation, insufficient or unsuitable lubrication, over-load, impact load vibration, excessive temperature, contamination by abrasive matter, ingress of harmful liquids, and stray electric currents. Most common modes of failure include flaking or pitting (fatigue), cracks or fractures, creep, smearing, wear, softening, indentation, fluting, and corrosion. The modes of failure are illustrated with examples from practice.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.power.c9001536
EISBN: 978-1-62708-229-7
... all were axial in orientation, except for the few small circumferential components shown in Fig. 4 . Fig. 4 Axial cracks on recirculation pump shaft revealed by dye-penetrant examination. A diffuse, wavy circumferential line marking the lower boundary of the chromium surface plating may...
Abstract
Argonne National Laboratory has conducted analyses of failed components from nuclear power-generating stations since 1974. The considerations involved in working with and analyzing radioactive components are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in service. The failures discussed are (1) intergranular stress-corrosion cracking of core spray injection piping in a boiling water reactor, (2) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressurized water reactor, (3) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (4) failure of pump seal wear rings by nickel leaching in a boiling water reactor.
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0001810
EISBN: 978-1-62708-180-1
... produces heavy score marks and polished regions, both in the bore of the inner ring and on the shaft. The end face of the ring, which is in frictional contact with the shoulder on the shaft, shows a characteristic scuffing effect typified by heavy circumferential score marks and, in severe cases, by short...
Abstract
Rolling-element bearings use rolling elements interposed between two raceways, and relative motion is permitted by the rotation of these elements. This article presents an overview of bearing materials, bearing-load ratings, and an examination of failed bearings. Rolling-element bearings are designed on the principle of rolling contact rather than sliding contact; frictional effects, although low, are not negligible, and lubrication is essential. The article lists the typical characteristics and causes of several types of failures. It describes failure by wear, failure by fretting, failure by corrosion, failure by plastic flow, failure by rolling-contact fatigue, and failure by damage. The article discusses the effects of fabrication practices, heat treatment and hardness of bearing components, and lubrication of rolling-element bearings with a few examples.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.petrol.c9001179
EISBN: 978-1-62708-228-0
... immediately or gradually into a circumferential transverse crack ( Fig. 2 ). Some pins also showed transverse fractures in the coarse thread ( Fig. 2 ). No fractures or cracks could be observed at the bore rods. It was subsequently established that steels of lower strength are considerably less sensitive...
Abstract
During natural gas drilling in the EMS region in 1956, considerable numbers of longitudinal cracks and transverse fractures occurred in the connecting pieces of the bore rods. The connectors were screwed onto the rods by means of a fine thread and tightly joined with it by shrinkage at 530 deg C. The connectors were made of SAE 4140 Cr-Mo steel. The material for the rod pipes was Fe-0.4C-1Mn steel. Structural stresses played a role in the cracking. Iron sulfide formed on the fracture planes and flake-like stress cracks occurred in the steel. The hydrogen sulfide content of the gas was the cause of damage. Hydrogen liberated by reaction with the iron caused the formation of iron sulfide after penetration of the steel, which had an explosive effect during molecular separation under high pressure. This in turn caused the crack formation in conjunction with the external and residual stresses.
Series: ASM Failure Analysis Case Histories
Publisher: ASM International
Published: 01 June 2019
DOI: 10.31399/asm.fach.modes.c9001516
EISBN: 978-1-62708-234-1
... Abstract This paper deals with disk drive failures that occur in the interface area between the head and disk. The failures often lead to the loss of stored data and are characterized by circumferential microscratches that are usually visible to the unaided eye. The recording media in disk...
Abstract
This paper deals with disk drive failures that occur in the interface area between the head and disk. The failures often lead to the loss of stored data and are characterized by circumferential microscratches that are usually visible to the unaided eye. The recording media in disk drives consists of a metal, glass, ceramic, or plastic substrate coated with a magnetic material. Data errors are classified as ‘soft’ or ‘hard’ depending on their correctability. Examination has shown that hard errors are the result of an abrasive wear process that begins with contact between head and disk asperities. The contact generates debris that, as it accumulates, increases contact pressure between the read-write head and the surface of the disk. Under sufficient pressure, the magnetic coating material begins wearing away, resulting in data loss.
1