Robustness of Detection Method for Clamp Force Against Configuration Error in Bolt/Nut Assemblies

2020 ◽  
Author(s):  
Shinji Hashimura ◽  
Kai Kubota ◽  
Nozomu Ohmi ◽  
Kyoichi Komatsu
Keyword(s):  
Detection Method ◽  
Tensile Force ◽  
Fe Analysis ◽  
Detection Accuracy ◽  
Bearing Surface ◽  
Clamp Force ◽  
Squareness Error ◽  
Before And After ◽  
The Relationship

Abstract Reliability of bolt/nut assemblies directly influences the quality of machines and structures. It is most important to control and maintain the clamp force of bolt/nut assemblies to secure reliability. However it is not easy to control the clamp force during tightening. And it is also difficult to detect the clamp force after tightening. In our previous study, we proposed a method to easily detect the clamp force of bolt/nut assemblies that have already been tightened. In the method, the bolt thread portion protruding from the nut is pulled while supporting the nut’s upper surface. The relationship between the tensile force and the displacement at the pulling point differs before and after the tensile force reaches the clamp force. The method can detect the tensile force at the point where the relationship changes as the clamp force. In this study, robustness of the detection method for the squareness error of the bearing surface of clamped parts has been investigated by FE analysis and experiments. The results of the FE analysis showed that the squareness error of the bolt bearing surface does not have an influence on the detection accuracy. The results indicate that the detection method has robustness for the squareness error of bolt bearing surfaces. Contrary to that, the experimental results show that the squareness error does have a clear influence on the detection accuracy. The averages of detection error in the experiments increased about 10% with an increase in squareness error. It is considered that the error was caused because the mating thread surfaces did not separate when the tensile force reached the clamp force.

scholarly journals Influence of Configuration Error in Bolted Joints on Detection Error of Clamp Force Detection Method

2021 ◽  
Vol 15 (4) ◽  
pp. 396-403
Author(s):  
Shinji Hashimura ◽  
Hisanori Sakai ◽  
Kai Kubota ◽  
Nozomi Ohmi ◽  
Takefumi Otsu ◽  
...  
Keyword(s):  
Tensile Force ◽  
Bolted Joints ◽  
Detection Accuracy ◽  
Bolted Joint ◽  
Detection Error ◽  
Bearing Surface ◽  
Force Detection ◽  
Clamp Force ◽  
Squareness Error ◽  
The Relationship

Clamp force errors in bolted joints often cause accidents in various mechanical structures. Therefore, the clamp force must be controlled accurately and maintained for securing the reliability of mechanical structures such as vehicles. However, the clamp force cannot be controlled easily during tightening. Moreover, it is difficult to detect the clamp force after tightening. We previously proposed a method to easily detect the clamp force of a bolted joint that has been tightened. In that method, the bolt thread protruding from the nut is pulled while the nut’s upper surface is supported. The relationship between tensile force and displacement at the pulling point where the tensile force is applied differs before and after the tensile force reaches the clamp force. The method detects the tensile force at the point, where the relationship changes, as the clamp force. In this study, we investigate the influence of squareness error on the bearing surface of the clamped part in a bolted joint on the detection error of the method using experiments and finite element (FE) analysis. The experimental results show that the squareness error has an influence on the detection accuracy. The average detection error in the experiments increases by approximately 10% with an increase in the squareness error. To understand the cause of this phenomenon, we investigate the effects of backlash between mating thread surfaces of bolts and nuts on the detection error. The results show that the error decreased because of the backlash. Consequently, it is assumed that the error is caused by the non-separation of the mating thread surfaces when the tensile force reached the clamp force. Furthermore, the FE analysis results show that the squareness error on the bearing surface of the clamped part has an influence of the squareness error on the detection accuracy. The results indicate that we should control the tolerance of squareness errors on the bearing surface of the clamped part when the clamp force detection method is applied to bolted joints.

APPLICATION OF THE ATP-BIOLUMINESCENCE METHOD TO ASSESS THE QUALITY OF SANITATION OF MILKING EQUIPMENT

2020 ◽  
Vol 1 (4) ◽  
pp. 468-472
Author(s):  
P.A. Popov ◽  
◽  
D.V. Gruznov ◽  
S.V. Tokarev ◽  
◽  
...  
Keyword(s):  
Dairy Farms ◽  
Laboratory Studies ◽  
Before And After ◽  
Atp Bioluminescence ◽  
Microbial Number ◽  
Proportional Relationship ◽  
The Relationship ◽  
Number Of Bacteria ◽  
Bioluminescence Method

The article presents the results of determining the relationship between the total microbial number and microbial ATP on the surface of milking equipment before and after treatment with neutral anolyte ANK-SUPER. The possibility of using the ATP-bioluminescence method to control the quality of sanitation of milking equipment on dairy farms is shown. Laboratory studies revealed a proportional relationship between the level of bacterial ATP and the number of bacteria on the surface of milking equipment before and after sanitation.

The Study on High Precision 3D Detection Method of Steel Plate Surface Based on Structured Light

2012 ◽  
Vol 572 ◽  
pp. 338-342 ◽  
Author(s):  
Zhi Guo Liang ◽  
Quan Yang ◽  
Ke Xu ◽  
Fei He ◽  
Xiao Chen Wang ◽  
...  
Keyword(s):  
Surface Quality ◽  
Steel Plate ◽  
Detection Method ◽  
Structured Light ◽  
Detection Methods ◽  
Measurement Technology ◽  
Detection Accuracy ◽  
Plate Surface ◽  
Factors Affecting

Structured light 3D measurement technology with its simple structure, non-contact measurement, fast measurement speed and other advantages, has been widely used. Steel plate surface quality detection is not confined to the two-dimensional feature of gray detection, and local topography measurement for surface quality of steel plate detection becomes increasingly important. In this paper, steel plate surface 3D detection method based on structured light and the factors affecting the measurement accuracy are analyzed. Several effective methods of improving 3D detection accuracy are put forward. Compared with the traditional structured light 3D detection methods, the detection accuracy of new methods is remarkably improved, thus possessing better application values.

scholarly journals Budget performance indicators: theoretical and practical aspects

2021 ◽  
Vol 2021 (1) ◽  
pp. 46-63
Author(s):  
Serhii YUSHKO ◽  
Keyword(s):  
Budget Deficit ◽  
The State ◽  
Planning System ◽  
Budget Management ◽  
Budget Planning ◽  
Absolute Value ◽  
Before And After ◽  
The Relationship ◽  
Budget Execution

The article examines the indicators on the basis of which the budget execution in Ukraine is assessed. Budget revenues and expenditures are characterized. The paper demonstrates the features of calculating the budget deficit (surplus) in Ukraine before and after 2004 year, emphasizing that despite the special place of this indicator in the budget planning system, for various reasons for a number of years there was neglect of current regulations legislation and world experience in budget deficit management. It is emphasized the imperfection of the budget deficit indicator due to its inherent shortcomings, concluding that the absolute value of the budget deficit is important in connection with another indicator – budget financing. The components of budget financing are named and characterized. It was found that the most important role in the context of balancing the main budget of the state belongs to debt operations. It is demonstrated the relationship between indicators of budget deficit and financing (their modular values are the same), revenues and expenditures (identical provided the balances at the beginning and end of the reporting period), net borrowing and the amount of public debt (the value of the latter increases / decreases by the amount net borrowing). The examples of specific budget years demonstrate the facts of exceeding the total amount of funding (budget deficit) by net borrowings of the state; the conclusion about the significance of the indicator of net borrowings in assessing the state of public finances is drawn; the need for further search for ways to improve the quality of budget management, thoughtful borrowing planning, the implementation of active budget operations with securities is stressed.

scholarly journals Correlation between Psychosocial Distress and Quality of Life in Patients with Nasopharyngeal Carcinoma following Radiotherapy

2018 ◽  
Vol 2018 ◽  
pp. 1-4 ◽  
Author(s):  
Xiaolan Wang ◽  
Yue Lv ◽  
Wen Li ◽  
Chen Gan ◽  
Haijun Chen ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Psychological Distress ◽  
Nasopharyngeal Carcinoma ◽  
Significant Negative Correlation ◽  
Psychosocial Distress ◽  
Time Points ◽  
Significant Difference ◽  
Before And After ◽  
The Relationship

The aim of this study was to investigate the relationship between psychosocial distress and quality of life (QOL) in patients with nasopharyngeal carcinoma (NPC) after radiotherapy. Fifty-three patients with an initial diagnosis of NPC were enrolled in this study. The psychological Distress Thermometer (DT) and Functional Assessment of Cancer Therapy-Head & Neck (FACT-H&N) were conducted before and after radiotherapy in NPC patients. We compared the differences in psychological distress and QOL before and after radiotherapy and analyzed the correlation between psychological distress and QOL after radiotherapy. The performance on the DT was 6.60 ± 1.42 and 2.81 ± 1.43 before and after chemotherapy, respectively, with a significant difference between the time points (t = -13.73,P< 0.01). The performance on the FACT-H&N was 68.30 ± 6.14 and 39.84 ± 6.14 before and after chemotherapy, respectively, with a significant difference between the time points (t = -19.9,P< 0.01). There was a significant negative correlation between the DT score and the FACT-H&N score (r = -3.64,P< 0.01). Patients with NPC experience different degrees of psychological distress, an important factor that affects quality of life, after radiotherapy.

On-Line Detection Method for Automobile Frame Side Rail Process Holes

2012 ◽  
Vol 616-618 ◽  
pp. 1993-1996
Author(s):  
Yu Zhuo Men ◽  
Hai Bo Yu ◽  
Hua Wang ◽  
Jin Gang Gao ◽  
Xin Pan
Keyword(s):  
Machine Vision ◽  
Detection Method ◽  
Detection System ◽  
Ccd Camera ◽  
Line Detection ◽  
Detection Accuracy ◽  
Side Rail ◽  
On Line ◽  
System Prototype

On-line detection method for automobile frame side rail process holes is proposed in this articled. It is achieved by virtue of machine vision technology detection method. Many images captured by CCD camera are processed and analyzed to finally complete the automatic detection of automobile chassis frame process holes. Machine vision technology is applied to achieve the on-line detection of machining quality of frame side rail mounting holes. The developed detection system prototype has very high detection accuracy.

scholarly journals Az interdiszciplináris rehabilitáció hatása spondylitis ankylopoeticában szenvedő betegekben

2016 ◽  
Vol 157 (28) ◽  
pp. 1126-1132
Author(s):  
Béla Hegedűs ◽  
János Varga ◽  
Attila Somfay
Keyword(s):  
Quality Of Life ◽  
Ankylosing Spondylitis ◽  
Lung Function ◽  
Rehabilitation Program ◽  
Physiological Variables ◽  
Before And After ◽  
Effective Program ◽  
The Relationship ◽  
Functional Indices

Introduction: Complex pulmonary assessment related to respiratory manifestation in patients with ankylosing spondylitis may contribute to adaptation of an appropriate rehabilitation program. Aim: To examine the relationship between lung function, exercise physiological variables and change in quality of life after rehabilitation in patients with ankylosing spondylitis. Method: 5 patients in Seyfried’s Stage 2 and 11 patients in Stage 3 underwent spinal physiotherapy, ultrasound, massage and paraffin Pack, 15 times each, followed by a high-intensity cycling 3 times a week for 8 weeks. The Bath Ankylosing Spondylitis Disease Activity and Bath Ankylosing Spondylitis Functional Indexes were recorded before and after rehabilitation. Lung function with exercise physiological variables were examined after rehabilitation. Results: Both indexes showed a post-treatment significant improvement compared to the initial scores (p<0.05). These functional indices correlated with lung function at rest and physiological variables during exercise (p<0.05). Conclusions: Based on this study, it is possible that an initial pulmonary assessment may serve to develop a more effective program for ankylosing spondylitis. Orv. Hetil., 2016, 157(28), 1126–1132.

scholarly journals Quality Detection System of Transparent Nonel Tubes Based on Image Processing

2015 ◽  
Vol 9 (1) ◽  
pp. 697-702
Author(s):  
Guodong Sun ◽  
Wei Xu ◽  
Lei Peng
Keyword(s):  
Image Processing ◽  
Detection Method ◽  
Detection System ◽  
Recognition Rate ◽  
Human Vision ◽  
Detection Methods ◽  
Detection Accuracy ◽  
External Diameter ◽  
Quality Detection

The traditional quality detection method for transparent Nonel tubes relies on human vision, which is inefficient and susceptible to subjective factors. Especially for Nonel tubes filled with the explosive, missed defects would lead to potential danger in blasting engineering. The factors affecting the quality of Nonel tubes mainly include the uniformity of explosive filling and the external diameter of Nonel tubes. The existing detection methods, such as Scalar method, Analysis method and infrared detection technology, suffer from the following drawbacks: low detection accuracy, low efficiency and limited detection items. A new quality detection system of Nonel tubes has been developed based on machine vision in order to overcome these drawbacks. Firstly the system architecture for quality detection is presented. Then the detection method of explosive dosage and the relevant criteria are proposed based on mapping relationship between the explosive dosage and the gray value in order to detect the excessive explosive faults, insufficient explosive faults and black spots. Finally an algorithm based on image processing is designed to measure the external diameter of Nonel tubes. The experiments and practical operations in several Nonel tube manufacturers have proved the defect recognition rate of proposed system can surpass 95% at the detection speed of 100m/min, and system performance can meet the quality detection requirements of Nonel tubes. Therefore this quality detection method can save human resources and ensure the quality of Nonel tubes.

scholarly journals Research on the Fairness of MPACC Selection Based on Examiner Heterogeneity

2021 ◽  
Vol 235 ◽  
pp. 03010
Author(s):  
Yan Wang ◽  
Zhuqian He ◽  
Jingjie Zheng
Keyword(s):  
Regression Model ◽  
Test Scores ◽  
Test Results ◽  
Before And After ◽  
The Relationship ◽  
Selection Of

The selection of MPACC (Master of Professional Accountant) is a key step in the training of senior accounting personnel. This paper examines the relationship between examiner heterogeneity and MPACC second test scores. We try to clarify the reason for the unfair phenomenon because of the heterogeneity of examiners in MPACC second test results and seek ways to solve this problem. The study found that the MPACC second test results are unfair. This unfairness is caused by the heterogeneity of the examiner. However, standardized algorithms balance the differences in MPACC examiner heterogeneity. The regression model was constructed by using the MPACC second test scores before and after standardization, which verified the existence of examiner heterogeneity and the effect of the standardized algorithm on the examiner heterogeneity. This article is based on the differences of MPACC second test scores due to examiner’s heterogeneity. We propose the application of standardized algorithm, which will play an important role in improving the quality of MPACC enrollment and promoting the training of senior accounting personnel.

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