Axial load distribution and self-loosening behavior of bolted joints subjected to torsional excitation

2021 ◽  
Vol 119 ◽  
pp. 104985
Author(s):  
Xuetong Liu ◽  
Xue Mi ◽  
Jianhua Liu ◽  
Laohu Long ◽  
Zhenbing Cai ◽  
...  
Keyword(s):  
Load Distribution ◽  
Axial Load ◽  
Bolted Joints ◽  
Torsional Excitation

Experimental and numerical studies of bolted joints subjected to torsional excitation

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840083 ◽  
Author(s):  
Xuetong Liu ◽  
Jianhua Liu ◽  
Huajiang Ouyang ◽  
Zhenbing Cai ◽  
Jinfang Peng ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Hysteresis Loops ◽  
Element Model ◽  
Bolted Joints ◽  
Torsional Angle ◽  
Numerical Studies ◽  
Dimensional Finite Element ◽  
Torsional Excitation ◽  
Three Dimensional Finite Element ◽  
Angular Amplitude

The dynamic response of bolted joints subjected to torsional excitation is investigated experimentally and numerically. First, the effects of the initial preload and the angular amplitude on axial force loss of the bolt were studied. Second, the change of hysteresis loops with the increasing number of loading cycles was found under a larger torsional angle. At last, a fine-meshed three-dimensional finite element model was built to simulate the bolted joint under torsional excitation, from which the hysteresis loops were obtained under varying angular amplitudes. The results of numerical analysis are in good agreement with those of experiments.

Experimental study of the nature of the load distribution on the turns of the thread of the planetary roller-screw mechanism

2019 ◽  
Author(s):  
O.A. Ryakhovskiy ◽  
A.S. Marokhin ◽  
A.N. Vorobyev ◽  
O.A. Khachirova
Keyword(s):  
Load Distribution ◽  
Axial Load ◽  
Flat Surface ◽  
Experimental Setup ◽  
Feed Drives ◽  
The Press ◽  
Roller Screw ◽  
Screw Mechanism ◽  
Force Displacement ◽  
Made In

The article considers the effect of axial load on the turns of the thread of the planetary roller-screw converter of rotational motion into translational one. For this purpose an experimental setup was made in which the nut lies end-face on the flat surface of the press, a screw is screwed into it. The force is applied to the screw through a ball to distribute the load uniformly. The design of the machine for compression measurement allows automatic recording the axial mutual movement of tested mechanism parts when the loading force changes. Contact and displacement occur when the loading force reaches 300 N. The results are obtained in the form of a "force – displacement" graph. In the course of the experiment, the influence of step error on the uniformity of the contacts of the turns of the mating parts of the planetary roller-screw mechanism was checked. The results of the experiment are analyzed, the influence of inaccuracy of manufacturing thread of planetary roller-screw mechanism parts on its capacity for use in feed drives of various machines is considered.

scholarly journals Quality control of adjustment of clearances of ball bearing supports, dynamic devices rotor-type, according to parameters of acoustic emission signals

2021 ◽  
Vol 2131 (4) ◽  
pp. 042099
Author(s):  
Ye Lebedev ◽  
I Golikov ◽  
A Repin ◽  
L Bogatov
Keyword(s):  
Acoustic Emission ◽  
Axial Load ◽  
Rotation Axis ◽  
Experimental Studies ◽  
Bolted Joints ◽  
Rolling Bearings ◽  
Bearing Life ◽  
Ae Signals ◽  
Rotor Type ◽  
Rotary Type

Abstract The article is devoted to increasing the bearing life of dynamic rotary-type machines by controlling the uniformity of the distribution of the value of the preliminary axial load acting on the rolling bearings of the rotation axis of the power unit. The possibility of monitoring the axial load using acoustic emission (AE) signals is considered. The results of experimental studies of the kinematics of the ball movement relative to other bearing parts, depending on the tightening torque of bolted joints, estimated by the parameters of AE signals, are presented.

scholarly journals ANALYSIS FOR AXIAL LOAD DISTRIBUTION IN PILE IN A PILED RAFT FOUNDATION STIFF CLAY BY FINITE ELEMENT

2017 ◽  
Vol 5 (3) ◽  
pp. 193-197
Author(s):  
Sanjeev Gill ◽  
Seema Rani
Keyword(s):  
Finite Element ◽  
Load Distribution ◽  
Axial Load ◽  
Three Dimensional ◽  
Nonlinear Finite Element ◽  
Nonlinear Finite Element Method ◽  
Piled Raft ◽  
Piled Raft Foundation ◽  
Raft Foundation ◽  
Stiff Clay

In this paper piled raft foundation has been analysed by nonlinear finite element method. The three dimensional nonlinear finite element analyses predict the actual behaviour of axial load distribution. The axial load variation is nonlinear for all the piles. For all pressure the element stress is more than the element stress. For any pressure the nodal deflection is maximum at top and minimum at bottom. Up to certain height the element stress is almost zero for all pressures. After that height the element stress increases with increase in height. The element stress increases with increase in pressure the measurement of axial load distribution in pile in field is very difficult and costly.

718 Analysis of Load Distribution of Nut in the Bolted joints

2007 ◽  
Vol 2007.82 (0) ◽  
pp. _7-18_
Author(s):  
Yoshihiro KUBOTA ◽  
Mitsuo KOBAYASHI ◽  
Naoki SATOH ◽  
Takashi KATOH ◽  
Kaoru HONGO
Keyword(s):  
Load Distribution ◽  
Bolted Joints

852 Influence of Height of Nut on Load Distribution of Bolted Joints : Comparison of analysis and experiment

2012 ◽  
Vol 2012 (0) ◽  
pp. 218-219
Author(s):  
Hisashi SAITO ◽  
Mitsuo KOBAYASHI ◽  
Jianmei HE ◽  
Yoshiki GOTOH ◽  
Katsumi HUKUDA ◽  
...  
Keyword(s):  
Load Distribution ◽  
Bolted Joints

Nonlinear Behaviour of Equivalent Stiffness of Plates Clamped by Bolted Joints Under Loading

2009 ◽  
Author(s):  
Tomohiro Naruse ◽  
Yoji Shibutani
Keyword(s):  
Axial Load ◽  
Bending Moment ◽  
Internal Force ◽  
Bolted Joints ◽  
Axial Stiffness ◽  
Nonlinear Behaviour ◽  
Equivalent Stiffness ◽  
Contact Conditions ◽  
Linear Behaviour ◽  
Load Displacement

The equivalent stiffness of clamped plates is needed not only to evaluate the strength of bolted joints but also to estimate the deformation and vibration characteristics of practical structures with many bolted joints. The axial stiffness and bending stiffness of clamped plates were estimated using finite element (FE) analyses while taking the contact conditions on bearing surfaces and between plates into account. We constructed FE models with an M10 bolt and plate thicknesses of 3.2, 4.5, 6.0, or 9.0 mm, and subjected them to an axial load and a bending moment. The axial compliance was estimated using the load-displacement relation obtained from the FE results. When the axial load was lower than 110% of the clamping force, the load-displacement relation showed linear behaviour and the axial compliance was almost constant. When the axial load was higher than that, the axial compliance varied nonlinearly with changes in the contact conditions between clamped plates. The compliances of the clamped plates were compared with those specified in the German engineering society code VDI 2230 (2003), in which equivalent conical compressive stress fields in the plates had been assumed. When the load-displacement relation behaves linearly, the axial and bending compliances obtained in FE analysis can basically be expressed by the VDI 2230 (2003) code. However, this code gives the slightly large axial stiffness, and thus the internal force borne to the bolt is predicted in a little bit unsafe estimation. In addition, the code is not suitable for application in the case of clamped plates with different thicknesses due to the assumptions it makes with respect to models.

Re-mobilization of pile shaft friction after an earthquake

2013 ◽  
Vol 50 (9) ◽  
pp. 979-988 ◽  
Author(s):  
M.E. Stringer ◽  
S.P.G. Madabhushi
Keyword(s):  
Hydraulic Conductivity ◽  
Load Distribution ◽  
Axial Load ◽  
Soil Layer ◽  
Pile Group ◽  
Excess Pore Pressure ◽  
Vertical Loading ◽  
Soil Settlement ◽  
Excess Pore Pressures ◽  
Excess Pore

During strong earthquakes, significant excess pore pressures can develop in saturated soils. After shaking ceases, the dissipation of these pressures can cause significant soil settlement, creating downward-acting frictional loads on piled foundations. Additionally, if the piles do not support the full axial load at the end of shaking, then the proportion of the superstructure’s vertical loading carried by the piles may change as a result of the soil settlement, further altering the axial load distribution on piles as the soil consolidates. In this paper, the effect of hydraulic conductivity and initial post-shaking pile head loading is investigated in terms of the changing axial load distribution and settlement responses. The investigation is carried out by considering the results from four dynamic centrifuge experiments in which a 2 × 2 pile group was embedded in a two-layer profile and subjected to strong shaking. It is found that large contrasts in hydraulic conductivity between the two layers of the soil model affected both the pile group settlements and axial load distribution. Both these results stem from the differences in excess pore pressure dissipation, part of which took place very rapidly when the underlying soil layer had a large hydraulic conductivity.

Providing Cyclic Robustness of Bolted Joints in Case of Assembly with Implementation of Anaerobic Materials

2019 ◽  
Vol 952 ◽  
pp. 3-12
Author(s):  
Igor Ivanovich Voyachek ◽  
Milan Sága ◽  
Zuzana Ságová ◽  
Denis Viktorovich Kochetkov ◽  
Vladimir Zinovievich Zverovschikov ◽  
...  
Keyword(s):  
Stress Concentration ◽  
Load Distribution ◽  
Crack Formation ◽  
Rupture Strength ◽  
High Stress ◽  
Bolted Joints ◽  
High Stress Concentration ◽  
Materials Modelling ◽  
Nonuniform Load ◽  
Elastic Layers

Stress concentration in thread roots and nonuniform load distribution along thread turn are the major disadvantages of bolted joints. Under changing cyclic loads on areas of high stress concentration crack formation and destruction of parts occur. In addition, the fretting corrosion processes activate in the areas of contact between thread turns. The purpose of the work is to increase rupture strength of bolted joints under the action of cyclic forces by decreasing stress concentration and reducing movements in contact zone of mating parts in case of assembly with implementation of anaerobic materials. Modelling of bearing strength of bolted joints is conducted according to finite element method, with theory of contact interaction between mating surfaces being used. The results of experimental research are given. Anaerobic materials which polymerize in area of thread contact of parts are used. It was established that assembly with implementation of anaerobic material allows unloading of thread turns because the part of external load is received by elastic layers of the polymerized anaerobic material. In this case the level and the concentration of stress in thread roots reduce, relative movements are decreased, the joint becomes more rigid and its cyclic robustness grows.

A Novel Formulation of Elastic Interaction in Gasketed Bolted Joints

2007 ◽  
Author(s):  
Ali A. Alkelani ◽  
Sayed A. Nassar ◽  
Basil A. Housari
Keyword(s):  
Mathematical Model ◽  
Load Distribution ◽  
Elastic Interaction ◽  
Bolted Joints ◽  
Good Prediction ◽  
Proposed Model ◽  
Joint Tightening ◽  
The Mathematical Model ◽  
Bolt Spacing ◽  
Initial Assembly

A novel mathematical model is proposed for studying elastic interaction in gasketed bolted joints. The model predicts the tension changes in tightened bolts due to the subsequent tightening of other bolts in the joint. It also predicts the final clamp load distribution after the completion of joint tightening. The model is used to investigate the effect of various factors on the elastic interaction phenomenon; factors include the gasket thickness, bolt spacing, fastener preload level, and the tightening sequence of various bolts. Experimental verification is provided for the validation of the mathematical model. Experimental and analytical results are presented and discussed. The proposed model provides good prediction of the final clamp load in the joint. Moreover, the proposed model may be used to determine the level of initial bolt tension in each bolt that would be necessary to achieve the desired level of uniform clamp load in the joint at initial assembly.

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