Comparative analysis of damage criteria for screw rolling using computer simulation

Two-high screw rolling of billets was carried out using a MISIS-130D rolling mill. AISI 321 steel billets were deformed with feed angles of rolls of 6°, 12°, 18° and 24°. The diameter reduction was 17%, with the initial billets’ diameter being 60 mm. An axial fracture, the so-called Mannesmann effect, of the billets was observed after screw rolling. The experimental rolling was simulated using QForm finite element method software. Initial and boundary conditions were set in concordance with the experimental rolling. Several damage criteria were used for fracture prediction during computer simulation. The results of computer simulation of fracture prediction were compared with the billets fracture after screw rolling for stationary and non-stationary stages. The most effective parameter (in terms of fracture prediction) is triaxiality. The distribution of this parameter showed that the higher the feed angle value is, the lower the fracture risk is. Notably, the risk of fracture is lower at a stationary stage compared with the same risk of fracture at a non-stationary stage; the listed trends agree with experimental rolling results. The Oyane, Ayada, Brozzo, and Cockroft-Latham Normalized criteria are partly effective. These criteria are ineffective for fracture prediction 6 degrees feed angle of rolls because they showed that fracture is most probable at the billet’s surface, which contradicts the experimental rolling results. All these criteria are partly effective when predicting a less fracture risk at a stationary stage compared with the same criteria at a non-stationary stage or when predicting a decrease of fracture with increasing the rolls feed angle.

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WHO absolute fracture risk models (FRAX): Do clinical risk factors improve fracture prediction in older women without osteoporosis?

Journal of Bone and Mineral Research ◽

10.1002/jbmr.372 ◽

2011 ◽

Vol 26 (8) ◽

pp. 1774-1782 ◽

Cited By ~ 56

Author(s):

Teresa A Hillier ◽

Jane A Cauley ◽

Joanne H Rizzo ◽

Kathryn L Pedula ◽

Kristine E Ensrud ◽

...

Keyword(s):

Risk Factors ◽

Fracture Risk ◽

Older Women ◽

Fracture Prediction ◽

Clinical Risk Factors ◽

Risk Models ◽

Clinical Risk

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Relationship between diffuse idiopathic skeletal hyperostosis and fragility vertebral fracture: a prospective study in older men

Rheumatology ◽

10.1093/rheumatology/keaa517 ◽

2020 ◽

Author(s):

Anaïs Guiot ◽

Charline Estublier ◽

Marine Gaude ◽

Pawel Szulc ◽

Roland Chapurlat

Keyword(s):

Vertebral Fracture ◽

Fracture Risk ◽

Diffuse Idiopathic Skeletal Hyperostosis ◽

Older Men ◽

Fracture Prediction ◽

Intervertebral Space ◽

Disc Space Narrowing ◽

Disc Space ◽

Vertebral Fracture Risk ◽

A Prospective Study

Abstract Objective To analyse the risk of incident vertebral and non-vertebral fracture in men with DISH. Methods In 782 men ages 50–85 years, DISH was diagnosed using Resnick’s criteria. In men followed prospectively for 7.5 years, a radiographic incident vertebral fracture was defined by a decrease of ≥20% or ≥4mm in any vertebral height vs baseline. Self-reported incident non-vertebral fractures were confirmed by medical records. Results Men with DISH had higher BMD at the lumbar spine (P < 0.05), but not at other skeletal sites. After adjustment for confounders including disc space narrowing (DSN) and endplate irregularity, the risk of vertebral fracture was higher in men with DISH vs men without DISH [10/164 (6.1%) vs 16/597 (2.7%), P < 0.05; odds ratio (OR) 2.89 (95% CI 1.15, 7.28), P < 0.05]. DISH and low spine BMD were each associated with a higher vertebral fracture risk. The vertebral fracture risk was higher in men who had both DISH and severe DSN. DISH and endplate irregularities (EIs) were each associated with higher vertebral fracture risk. DISH, DSN and EIs define the intervertebral space dysfunction, which was associated with higher vertebral fracture risk [OR 3.99 (95% CI 1.45, 10.98), P < 0.01]. Intervertebral space dysfunction improved the vertebral fracture prediction (ΔAUC = +0.111, P < 0.05), mainly in men with higher spine BMD (>0.9 g/cm2; ΔAUC = +0.189, P < 0.001). DISH was not associated with the risk of non-vertebral fracture. Conclusion DISH is associated with higher vertebral fracture risk, independently of other risk factors. Assessment of the intervertebral space dysfunction components may improve the vertebral fracture prediction in older men.

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Effects of Anti-Diabetic Drugs on Fracture Risk: A Systematic Review and Network Meta-Analysis

Frontiers in Endocrinology ◽

10.3389/fendo.2021.735824 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yu-Sheng Zhang ◽

Yan-Dan Zheng ◽

Yan Yuan ◽

Shi-Chun Chen ◽

Bao-Cheng Xie

Keyword(s):

Systematic Review ◽

Fracture Risk ◽

Meta Analysis ◽

Statistical Significance ◽

Treatment Strategies ◽

Sex Distribution ◽

Risk Of Fracture ◽

Dipeptidyl Peptidase 4 ◽

Combining Data ◽

Glucagon Like Peptide 1

PurposeAvailable data on the effects of anti-diabetic drugs on fracture risk are contradictory. Therefore, our study aimed to analyze all available data on the effects of anti-diabetic drugs on fracture risk in type 2 diabetes mellitus (T2DM) patients.MethodsEmbase, Medline, ClinicalTrials.gov, and Cochrane CENTRAL were searched for relevant trials. All data analyses were performed with STATA (12.0) and R language (3.6.0). Risk ratio (RR) with its 95% confidence interval (CI) was calculated by combining data for the fracture effects of anti-diabetic drugs, including sodium–glucose co-transporter 2 (SGLT2) inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, meglitinides, α-glucosidase inhibitors, thiazolidinediones, biguanides, insulin, and sulfonylureas.ResultsOne hundred seventeen eligible randomized controlled trials (RCTs) with 221,364 participants were included in this study. Compared with placebo, trelagliptin (RR 3.51; 1.58–13.70) increased the risk of fracture, whereas albiglutide (RR 0.29; 0.04–0.93) and voglibose (RR 0.03; 0–0.11) decreased the risk of fracture. Other medications were comparable in terms of their effects on fracture risk, and no statistical significance was observed. In terms of fractures, voglibose (0.01%) may be the safest option, and trelagliptin (13.64%) may be the worst. Sensitivity analysis results were consistent with those of the main analysis. No statistically significant differences were observed in the regression coefficients of age (1.03; 0.32–2.1), follow-up duration (0.79; 0.27–1.64), and sex distribution (0.63; 0.15–1.56).ConclusionsWe found varied results on the association between the use of anti-diabetic drugs and fracture risk. Specifically, trelagliptin raised the risk of fracture, whereas voglibose and albiglutide showed benefit with statistical difference. Other drugs were comparable in terms of their effects on fracture risk. Some drugs (omarigliptin, sitagliptin, vildagliptin, saxagliptin, empagliflozin, ertugliflozin, rosiglitazone, pioglitazone, and nateglinide) may increase the risk of fracture, while others (such as dulaglutide, exenatide, liraglutide, semaglutide, lixisenatide, linagliptin, alogliptin, canagliflozin, dapagliflozin, glipizide, gliclazide, glibenclamide, glimepiride, metformin, and insulin) may show benefits. The risk of fracture was independent of age, sex distribution, and the duration of exposure to anti-diabetic drugs. When developing individualized treatment strategies, the clinical efficacy of anti-diabetic drugs must be weighed against their benefits and risks brought about by individual differences of patients.Systematic Review RegistrationThis Systematic Review was prospectively registered on the PROSPERO (https://www.crd.york.ac.uk/PROSPERO/, registration number CRD42020189464).

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A Review of the Potential Application of Osteocyte-Related Biomarkers, Fibroblast Growth Factor-23, Sclerostin, and Dickkopf-1 in Predicting Osteoporosis and Fractures

Diagnostics ◽

10.3390/diagnostics10030145 ◽

2020 ◽

Vol 10 (3) ◽

pp. 145 ◽

Cited By ~ 1

Author(s):

Fitri Fareez Ramli ◽

Kok-Yong Chin

Keyword(s):

Growth Factor ◽

Fracture Risk ◽

Fibroblast Growth Factor ◽

Fibroblast Growth Factor 23 ◽

Fracture Prediction ◽

Current Evidence ◽

Fibroblast Growth ◽

Osteoporosis Screening ◽

Potential Marker ◽

Dickkopf 1

Bone turnover markers (BTMs) derived from the secretory activities of osteoblasts and the matrix-degrading activities of osteoclasts are useful in monitoring the progression of osteoporosis and the efficacy of anti-osteoporotic treatment. However, the usefulness of BTMs in predicting osteoporosis remains elusive. Osteocytes play a central role in regulating bone formation and resorption. The proteins secreted by osteocytes, such as fibroblast growth factor-23 (FGF23), sclerostin (SOST), and dickkopf-1 (DKK1), could be candidates for osteoporosis screening and fracture prediction. This review summarizes the current evidence on the potential of osteocyte-related proteins as biomarkers for osteoporosis and fracture prediction. The literature reports that SOST may be a potential marker for osteoporosis screening but not for fracture prediction. FGF23 is a potential marker for increased fracture risk, but more studies are needed to confirm its usefulness. The role of DKK1 as a marker to predict osteoporosis and fracture risk cannot be confirmed due to a lack of consistent evidence. In conclusion, circulating osteocyte markers are potential osteoporosis biomarkers, but more studies are warranted to validate their clinical use.

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Forming Features and Properties of Titanium Alloy Billets After Radial-Shear Rolling

Materials ◽

10.3390/ma12193179 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3179 ◽

Cited By ~ 4

Author(s):

Skripalenko ◽

Galkin ◽

Vladimirovich Karpov ◽

Romantsev ◽

Kaputkina ◽

...

Keyword(s):

Computer Simulation ◽

Titanium Alloy ◽

Rolling Mill ◽

Stress Triaxiality ◽

Grain Structure ◽

Structure Changes ◽

Ring Shape ◽

Accumulated Strain ◽

Experimental Rolling ◽

Radial Shear Rolling

Radial-shear rolling (RSR) of titanium alloy billets was realized in a three-high rolling mill. Experimental rolling was simulated using DEFORM software. The purpose was to reveal how stress-strain state parameters, grain structure and hardness vary along the billet’s radius in the stationary stage of the RSR process. It was also the goal to establish a relation between stress state parameters, hardness and grain structure. Changes in the accumulated strain and the stress triaxiality were established by computer simulation. Hardness and grain size changes were obtained after experimental rolling. The novelty aspect is that both computer simulation and experimental rolling showed that there is a ring-shape area with lowered strength in the billet’s cross-section. The radius of the ring-shape area was predicted as a result of the research.

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Study of the Tubular Billets Geometric Characteristics during Computer Simulation of the Rotary Piercing Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.946.788 ◽

2019 ◽

Vol 946 ◽

pp. 788-793

Author(s):

Vladimir A. Toporov ◽

Aleksandr Bogatov ◽

Danis Nukhov

Keyword(s):

Computer Simulation ◽

Contact Surface ◽

Research Methodology ◽

Deformation Zone ◽

Rotation Frequency ◽

Step Length ◽

Geometric Characteristics ◽

Feed Angle ◽

Tubular Billet ◽

Surface Length

The results of the computer simulation of the tubular billet rotary piercing process are presented. The research methodology of the deformation zone geometric ratios with due regard for the tubular billet change of shape at each helical curve step was developed .The changes pattern of the helical curve step length (li), quotient reduction (Δr/r0), ratio of the tubular billet radius to the contact surface width (r/b), contact surface length of the tubular billet (l0) with a roll, depending on the feed angle (β), roll rotation frequency (N) and plug nose extension at the gorge (Сg) was established.

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The relationships between structural organization, material properties, and loading conditions and the risk of fracture and fracture location in the femur

10.1101/2021.07.26.453913 ◽

2021 ◽

Author(s):

Todd L Bredbenner

Keyword(s):

Stress Response ◽

Fracture Risk ◽

Material Properties ◽

Structural Organization ◽

Proximal Region ◽

Loading Conditions ◽

Mineral Density ◽

Risk Of Fracture ◽

Increased Risk ◽

Structural Traits

Increased risk of skeletal fractures due to bone mass loss is a major public health problem resulting in significant morbidity and mortality, particularly in the case of hip fractures. Current clinical methods based on two-dimensional measures of bone mineral density (areal BMD or aBMD) are often unable to identify individuals at risk of fracture. The underlying hypothesis of this study was that combinations of femur structural traits are different for those femurs that suffer a fragility fracture within the proximal region of the femur and those that sustain a fracture in either the subtrochanteric or midshaft region of the femur, resulting in an "atypical femur fracture". Accordingly, the objective of this study was to determine the effects of varying combinations of structural traits, material properties, and loading conditions on femur stress response and the location of stress response variation using a validated parametric finite element model. Statistical shape and trait modeling of the femur was used to describe variability in the structural organization of a set of femurs in an efficient manner and the resulting description of structural variability was exploited to investigate how different mechanisms of fracture might occur, whether in the proximal region or in the subtrochanteric and midshaft region. In combination with parameters describing loading condition and material property variation, variation in structural organization is associated with regional increases in maximum principal stress and the percentage of bone expected to damage, and these increases are likely associated with increased fracture risk. The results of this study indicate that there are multiple pathways and combinations of descriptor variation that may result in increased fracture risk and that these pathways can lead to fracture in any region of the femur under both overload conditions, such as with sideways fall loading, and stance loading, which due to the repetitive nature may lead to the accumulation of fatigue damage within the bone and further impair bone condition and increased susceptibility to fracture.

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Socioeconomic variables and fracture risk in children and adolescents: a population-based study from northern Sweden

BMJ Open ◽

10.1136/bmjopen-2021-053179 ◽

2021 ◽

Vol 11 (10) ◽

pp. e053179

Author(s):

Erik Hedström ◽

Sead Crnalic ◽

Antonia Kullström ◽

Ingeborg Waernbaum

Keyword(s):

Fracture Risk ◽

Rate Ratio ◽

Population Based ◽

Income Quintile ◽

Northern Sweden ◽

Population Based Study ◽

Risk Of Fracture ◽

Socioeconomic Variables ◽

Generalised Linear Mixed Model ◽

Family Level

ObjectivesPrevious studies have investigated the association between socioeconomic characteristics and fractures among children, producing different results. In a population-based study, we previously found an increased risk of fractures among children living in an urban municipality compared with rural municipalities. This study aimed to evaluate the importance of socioeconomic variables for the incidence of fractures among 0–17 year olds.Setting, design and outcome measureWe present a longitudinal, observational study of a population 0–17 years of age. Data from an injury database were linked with additional socioeconomic data for the population at risk. These were 55 758 individuals residing within the primary catchment area of a regional hospital in northern Sweden. Using the number of fractures as the outcome, we fitted a generalised linear mixed model for a Poisson response with socioeconomic variables at the family level as independent variables while controlling for age, sex and place of residence.ResultsWe found a significant association between higher levels of family income and the risk of fracture, rate ratio 1.40 (1.28–1.52) p<0.001 when comparing the highest income quintile to the lowest as well as the number of siblings and the risk of fracture. Children with one or two siblings had a rate ratio of 1.28 (1.19–1.38) p<0.001 when compared with children with no siblings. Parents’ educational level and having a single parent showed no significant association with fractures. The previously observed association between municipalities and fracture risk was less pronounced when taking family-level socioeconomic variables into account.ConclusionOur results indicate that children from families with higher income and with siblings are at greater risk of sustaining fractures.

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