Solutions for Increasing the Bearing Capacity of Thrust Bearings

2014 ◽  
Vol 630 ◽  
pp. 208-219 ◽  
Author(s):  
Vasyl Martsynkovskyy ◽  
Volodymyr Yurko
Keyword(s):  
Bearing Capacity ◽  
Oil Consumption ◽  
Thrust Bearings ◽  
Consumption Ratio ◽  
Operating Modes ◽  
Axial Forces ◽  
High Efficient ◽  
Petroleum Chemical ◽  
Axial Shift ◽  
Rotor Balancing

Design faults, imperfect manufacturing processes, change of technological operating modes of the turbocompressors in gas, petroleum, chemical and petrochemical industry cause axial rotor shifts. Therefore, the task of manufacturing the high-efficient and reliable thrust bearings is important nowadays along with effective rotor balancing, methods of axial forces calculation considering possible operating modes, improvement of static electricity elimination system, protective and monitoring systems of the axial shift. Effective methods for increasing the bearing capacity of thrust bearings, applied by TRIZ Ltd, have been studied in the report. The accepted and realized on the operating equipment solutions have enabled to increase the bearing capacity of thrust bearings significantly and to reduce oil consumption ratio, keeping down location dimensions to the equipment.

Experiment of the SCT Joint under Complicated Loading

2011 ◽  
Vol 255-260 ◽  
pp. 607-613
Author(s):  
Bing Liao ◽  
Yong Feng Luo ◽  
Xiao Nong Guo
Keyword(s):  
Bearing Capacity ◽  
Loading Condition ◽  
Steel Structure ◽  
Force Transmission ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Roof Structure ◽  
Axial Forces ◽  
Out Of Plane ◽  
Water Sports

A radial-circle-lined grid shell, its height changed step by step in the radial direction, is adopted in the roof steel structure of the Citizen Water Sports Center in Jiangyin, China. And the Spatial Crossing Tubular (SCT) joint is used for the connection of pipe members. Because the force transmission in the roof structure is different from the traditional truss structure, a lot of SCT joints are in a complicated loading state. The joint forces include axial forces and in/out-of-plane moments. To investigate the mechanical behavior and the load-bearing capacity of a typical SCT joint in such complicated loading condition, a full size model test of the typical SCT joint is conducted. The test process is summarized in the paper, together with the finite element calculation of the typical SCT joint in test conditions. By comparing the numerical results with the test results, several significant parameters of the connection are investigated, including the stiffness change of the joint, the transmission mechanism of forces, the ultimate load-bearing capacity and the failure mode of the joint. After investigation, several useful suggestions are proposed for the SCT joint design. They are also valuable for the design of similar SCT joints under complicated loading condition.

scholarly journals ANALISIS KINERJA TIANG DENGAN VARIASI KEMIRINGAN DI DERMAGA “SJ” BANDAR LAMPUNG

2021 ◽  
Vol 4 (4) ◽  
pp. 823
Author(s):  
Dede Oktaferdian ◽  
Sunarjo Leman
Keyword(s):  
Bearing Capacity ◽  
Capacity Ratio ◽  
Axial Forces ◽  
Strength Capacity ◽  
Batter Piles ◽  
Field Planning

The design of the jetty cannot be separated from the use of piles as a foundation that supports the upper structure. The pile configuration affects the strength and stability of the structure. It may consist of only vertical piles or a combination of vertical and batter piles. This study analyzes and compares 10 types of pile configurations intending to determine the best pile configuration among the types analyzed. Type 1 is a pile configuration that is in accordance with the field planning of “SJ” jetty which consists of only vertical piles and type 2 to type 10 is a pile configuration that consists of a combination of vertical and batter piles with a slope ranging from 1H:12V to 1H:4V. The best configuration is determined based on the strength (capacity ratio), stiffness (deflection that occurs), and the axial bearing capacity of the pile. The process of modeling and analyzing the pile configurations are done using Midas Gen. The results showed that pile configuration type 8 with a combination of vertical and batter piles with a slope of 1H:6V is the best configuration with the smallest deflection and the axial forces of the vertical and batter piles are almost equal.ABSTRAKDesain dermaga tidak dapat dipisahkan dari penggunaan tiang sebagai fondasi yang menyangga struktur bagian atas. Konfigurasi tiang berpengaruh pada kekuatan dan stabilitas dari struktur dermaga. Konfigurasi tiang dapat terdiri dari tegak seluruhnya maupun kombinasi antara tiang tegak dan miring. Penelitian ini menganalisis dan membandingkan 10 tipe konfigurasi tiang dengan tujuan mendapatkan konfigurasi tiang terbaik di antara tipe-tipe yang dianalisis. Tipe 1 adalah konfigurasi tiang yang sesuai dengan perencanaan dermaga “SJ” berupa tiang tegak seluruhnya dan tipe 2 hingga tipe 10 adalah konfigurasi kombinasi tiang tegak dan miring dengan kemiringan 1H:12V hingga 1H:4V. Konfigurasi tiang terbaik ditentukan berdasarkan kekuatan (capacity ratio), kekakuan (defleksi yang terjadi), dan daya dukung aksial tiang. Model dan proses analisis dari seluruh konfigurasi tiang menggunakan program Midas Gen. Hasil analisis menunjukkan bahwa konfigurasi tiang tipe 8 dengan kombinasi tiang tegak dan miring dengan kemiringan 1H:6V adalah konfigurasi terbaik dengan defleksi terkecil serta gaya aksial tiang tegak dan miring yang hampir sama.

scholarly journals Axial Bearing Capacity Analysis of Pile Foundation using Nakazawa Method

Jurnal IPTEK ◽  
2020 ◽  
Vol 24 (1) ◽  
pp. 45-52
Author(s):  
Laras Laila Lestari ◽  
Jaka Propika ◽  
Aisyah Dwi Puspasari
Keyword(s):  
Bearing Capacity ◽  
Soil Type ◽  
Pile Foundation ◽  
Capacity Analysis ◽  
Calculation Methods ◽  
Soft Soils ◽  
N Value ◽  
Axial Forces ◽  
Friction Bearing ◽  
Friction Interaction

Pile foundation serves to distribute all the loads in the building to the ground. There are several calculation methods for bearing capacity of pile foundation, one of them is Nakazawa method. Nakazawa method adapted from calculation used in Japan where it is relevant for soft soils. The aim of this research is to obtain axial bearing capacity of pile foundation that can withstand axial forces using Nakazawa method. The parameter that used for the calculation is modified or average N-value (). The analysis result shows the  value is smaller than N existing, indicate that Nakazawa tend to use weaker value of N blows. It means the calculation is considered softer type of soils than the existing ones.The value of point bearing capacity, Rp, assimilate to the pattern of N-SPT. The result value of friction bearing, Rf, in respect of depth shows the linear trending. Rf along the pile depends on the friction interaction between soil and structure. This phenomena influenced by the soil type. The value of cohession along the pile augment, means the ability of soils to stick to the pile/structure is also high. It explains why the value of friction bearing is bigger in respect of depth.

scholarly journals Restoration of the Bearing Capacity of Damaged Transport Constructions Made of Corrugated Metal Structures

2021 ◽  
Vol 16 (2) ◽  
pp. 90-109
Author(s):  
Vitalii Kovalchuk ◽  
Mykola Sysyn ◽  
Yuriy Hnativ ◽  
Artur Onyshchenko ◽  
Maksym Koval ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Element Model ◽  
The Body ◽  
Railway Track ◽  
Soil Pressure ◽  
Metal Structures ◽  
Railway Line ◽  
Corrugated Shell ◽  
Axial Forces ◽  
Corrugated Metal

The paper deals with damages of transport constructions made of corrugated metal structures in the body of a railway track or a road during their operation. A constructive variant to restore the bearing capacity of structures was developed, which consists of installing an annular stiffening rib into the concave part of the corrugated metal profile. The main advantage of this method compared to the double corrugating method is the possibility of performing the reinforcement works during structure operation without interrupting the movement of transport vesicles. The study has proved that the reinforcement method significantly increases the carrying capacity of corrugated metal structures. A numerical finite element model was developed to determine the stress-strain state of structures made of corrugated metal structures reinforced with round stiffening ribs. The soil pressure on the corrugated shell in the model is taken into account with the application of radial and axial forces on the outer surface of the shell. It was determined that the most appropriate location of the ribs is in the centre of the building, where the reinforcement area corresponds to the width of the road or railway line. The advantage of this approach is the ability to more efficiently distribute the reinforcement material by selecting the ribs in the most loaded sections of corrugated metal structures.

scholarly journals Material flow control in plunge micro rotary swaging

2018 ◽  
Vol 190 ◽  
pp. 15014 ◽  
Author(s):  
Eric Moumi ◽  
Philipp Wilhelmi ◽  
Christian Schenck ◽  
Marius Herrmann ◽  
Bernd Kuhfuss
Keyword(s):  
Material Flow ◽  
Axial Direction ◽  
Axial Position ◽  
Rotary Swaging ◽  
Roll To Roll ◽  
Axial Forces ◽  
Micro Parts ◽  
Special Challenge ◽  
Axial Shift ◽  
Process Measurements

In rotary swaging, the material flow is not fully controlled by closure of the forming dies. This is especially noticeable in plunge rotary swaging of rod, where the workpiece is positioned into the forming zone und processed locally. As result, an uncontrolled elongation of the workpiece in axial direction takes place and an axial position shift of the workpiece relative to the dies occurs. This is a special challenge in production of linked micro parts, where single parts are interconnected in order to enable the handling as a strip and thereby a roll-to-roll production. The axial shift influences not only the subsequent positioning of neighbouring parts, but also the final geometry of the currently processed part. The presented investigation analyses the material flow during plunge micro rotary swaging on basis of in-process measurements of the workpiece shift on both sides of the forming zone as well as with the help of contour measurements of the processed parts. It is shown that the measured shift is strongly influenced by the workpiece clamping and fixation and that it can be controlled by applying low axial forces to the workpiece on one or both sides of the forming zone. Further, the geometry of the workpiece can be affected by these measures.

scholarly journals Field Performance of Open-Ended Prestressed High-Strength Concrete Pipe Piles Jacked into Clay

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4216 ◽  
Author(s):  
Hai-Lei Kou ◽  
Wen-Zhou Diao ◽  
Tao Liu ◽  
Dan-Liang Yang ◽  
Suksun Horpibulsuk
Keyword(s):  
Bearing Capacity ◽  
Static Loading ◽  
High Strength Concrete ◽  
Field Tests ◽  
Field Performance ◽  
High Strength ◽  
Loading Test ◽  
Strength Concrete ◽  
Axial Forces ◽  
Static Loading Test

The behavior of open-ended pipe piles is different from that of closed-ended pipe piles due to the soil plugging effect. In this study, a series of field tests were conducted to investigate the behavior of open-ended prestressed high-strength concrete (PHC) pipe piles installed into clay. Two open-ended PHC pipe piles were instrumented with Fiber Bragg Grating (FBG) sensors and jacked into clay for subsequent static loading tests. Soil plug length of the test piles was continuously measured during installation, allowing for calculation of the incremental filling ratio. The recorded data in static loading test were reported and analyzed. The distribution of residual forces after installation and the effect on the bearing capacity were also discussed in detail. The test piles were observed to be in partially plugged condition during installation. The measured ultimate shaft resistance and total resistance of the test piles were 639 and 1180 kN, respectively. The residual forces locked in the test piles after installation significantly affected the evaluation of the axial forces, and thus the shaft and end resistances. It tended to underestimate the end resistances and overestimate the shaft resistances if the residual forces were not considered in the loading test. However, the residual forces did not affect the total bearing capacity of open-ended PHC pipe piles in this study.

Thermohydrodynamic Analysis of Wide Thrust Bearings Operating in Turbulent Inertial Flow Regimes

1988 ◽  
Vol 110 (2) ◽  
pp. 327-334 ◽  
Author(s):  
S. J. Chowdhury ◽  
G. Ahmadi
Keyword(s):  
Bearing Capacity ◽  
Flow Regimes ◽  
Resistance Force ◽  
Load Bearing Capacity ◽  
Mean Velocity ◽  
Load Bearing ◽  
Thrust Bearings ◽  
Contraction Ratio ◽  
Inertial Flow ◽  
Inertial Terms

Wide thrust bearings operating in turbulent inertial flow regimes are studied. Isothermal and thermohydrodynamic performances of the bearing are analyzed. Integro-differential equations of motion, continuity, and energy equations are solved to yield pressure, mass-mean velocity, and temperature distributions. The effects of contraction ratio and film Reynolds number on the pressure field, load bearing capacity, flow rate and frictional resistance force of the bearing are examined. The effect of film temperature variation on the performance of bearing is studied and the result is compared with the isothermal case. It is observed that the viscous heating reduces the load bearing capacity to a significant extent. The effects of including the inertial terms are also considered. The results for inertial and noninertial cases are plotted and compared. It is shown that with the inclusion of the inertial terms the load bearing capacity somewhat increases. The results obtained are compared with the existing data and reasonable agreement is observed.

Experimental Study on the Mechanism of Lubrication in Hydrodynamic Porous Thrust Bearings With a Wavy Surface

1999 ◽  
Vol 121 (3) ◽  
pp. 538-545 ◽  
Author(s):  
Shigeru Ohtsuka ◽  
Motozo Hayakawa
Keyword(s):  
Friction Coefficient ◽  
Consumption Rate ◽  
Three Dimensional ◽  
Surface Porosity ◽  
Oil Consumption ◽  
Surface Conditions ◽  
Thrust Bearings ◽  
Lubrication Characteristics ◽  
Theoretical Application ◽  
Lubrication Conditions

Hydrodynamic fluid lubrication theory is applied to thrust bearings with three-dimensional, wave-shaped axial end surfaces. Optimizations of the wave height and surface porosity are experimentally determined using lubrication characteristics such as the friction coefficient and worn-out surface conditions. Lubrication characteristics such as the friction coefficient, temperature rise, thrust flotation, and oil consumption rate are evaluated for an estimation of life expectancy. In this research, the results of this theoretical application on thrust bearings clearly showed considerable improvement over conventional thrust bearings. Furthermore, this experimental research has clarified the lubrication conditions of various thrust-loaded axial end surfaces.

scholarly journals Experimental and Numerical Analysis of Large-Scale Circular Concrete-Filled Steel Tubular Columns with Various Constructural Measures under High Axial Load Ratios

2018 ◽  
Vol 8 (10) ◽  
pp. 1894 ◽  
Author(s):  
Lidong Zhao ◽  
Wanlin Cao ◽  
Huazhen Guo ◽  
Yang Zhao ◽  
Yu Song ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Bearing Capacity ◽  
Axial Load ◽  
Large Scale ◽  
Steel Tube ◽  
Test Results ◽  
Welded Steel ◽  
Axial Forces ◽  
Circular Steel Tube ◽  
Cfst Columns

To investigate the effect of constructional measures (including horizontal and vertical stiffeners, rebar cages, embedded steel tubes, and cavity welded steel plates) under high axial load ratios on the seismic performance of concrete-filled steel tubular (CFST) columns, quasi-static tests for six large-scale CFST columns with various constructional measures are performed. All specimens are subjected to identical axial forces. The failure mode, hysteresis characteristics, bearing capacity, stiffness degradation, ductility, and energy dissipation of specimens are analyzed. The study shows that the horizontal stiffener delays the occurrence and severity of column base buckling, the vertical stiffener improves the bending resistance capacity and initial stiffness of the member, the rebar cage improves the ductility, and the embedded circular steel tube significantly improves the member’s bearing capacity, ductility, and energy dissipation. When an internal circular steel tube and cavity welded steel plate are applied in tandem, the section steel ratio increases by 4.42% and the bearing capacity improves by 42.72%. A finite element model is created to verify test results, and simulation results match the test results well.

Measurement and Prediction of Centrifugal Compressor Axial Forces During Surge—Part I: Surge Force Measurements

2017 ◽  
Vol 140 (1) ◽  
Author(s):  
Klaus Brun ◽  
Sarah Simons ◽  
Rainer Kurz ◽  
Enrico Munari ◽  
Mirko Morini ◽  
...  
Keyword(s):  
Centrifugal Compressor ◽  
Operating Conditions ◽  
Force Measurements ◽  
Thrust Bearings ◽  
Axial Forces ◽  
Measured Time ◽  
Radial Forces ◽  
Gas Seals ◽  
Potential Damage ◽  
The Impact

Centrifugal compressor impellers and shafts are subject to severe fluctuating axial and radial forces when operating in surge. These forces can cause severe damage to the close clearance components of a centrifugal compressor such as the thrust and radial bearings, interstage and dry gas seals, and balance piston. Being able to accurately quantify the cyclic surge forces on the close clearance components of the compressor allows the user to determine whether an accidental surge event, or emergency shutdown (ESD) transient, has caused damage requiring inspection, repair, or part replacement. For the test, a 700 hp (∼520 kW) industrial air centrifugal compressor was operated in surge at speeds ranging from 7000 to 13,000 rpm and pressure ratios from 1.2 to 1.8. The axial surge forces were directly measured using axial load cells on the thrust bearings. Suction and discharge pressures, proximity probe axial shaft position, flows, and temperatures were also measured. Time domain and frequency plots of axial vibration and dynamic pulsations showed the impact of the operating conditions on surge force amplitudes and frequencies. A surge severity coefficient was also derived as a simple screening tool to evaluate the magnitude of potential damage to a compressor during surge.

Sign in / Sign up

Export Citation Format

Share Document