scholarly journals Influence of Bellows Setting on Its Spring Rate and on Temperature Adjustment of Electromechanical Thermostats

2016 ◽  
Vol 19 (2) ◽  
pp. 43-48
Author(s):  
Peter Haas ◽  
Milan Kadnár ◽  
František Tóth ◽  
Juraj Rusnák ◽  
Dušan Nógli
Keyword(s):  
Mechanical System ◽  
Critical Parameters ◽  
Spring Rate ◽  
Axial Movement ◽  
The Difference

Abstract The precision and stability of adjusted temperatures are critical requirements for electromechanical thermostats. The key element in meeting the requirement is a thermostat bellows. It is a convertor of pressure into force that actuates the mechanical system of the thermostat. Convolutions enabling the axial movement of the bellows cause that the bellows is partly behaving as a spring. Therefore, the bellows has its own spring rate. The setting of the bellows spring rate influences the critical parameters of the thermostat. The aim of the article is to find the difference between the setting done by bellows producer and setting done by thermostat producer and its influence on the thermostat adjustment.

Large Stroke Series Compliant Mechanism

2012 ◽  
Vol 490-495 ◽  
pp. 1104-1108 ◽  
Author(s):  
Ming Cai Shan ◽  
Wei Ming Wang ◽  
Shu Yuan Ma ◽  
Shuang Liu
Keyword(s):  
Theoretical Model ◽  
Maximum Stress ◽  
Compliant Mechanism ◽  
Critical Parameters ◽  
Element Analysis ◽  
Flexure Hinges ◽  
Body Model ◽  
System A ◽  
Rigid Body Model ◽  
The Difference

To increase the stroke of precision positioning system, a novel series compliant mechanism is presented which is based on elliptical flexure hinges. Pseudo-rigid-body model and energy method are applied to establish the theoretical model of stiffness and maximum stress, which are critical parameters for the large stroke compliant mechanism. The relationships are analyzed between geometric parameters of the series complaint mechanism, stiffness and maximum stress. According that, the series compliant mechanism is designed with the stroke more than 5mm and stiffness less than 3.2N/mm. The difference is less than 5% between the results of finite element analysis and theoretical model computation, which proves the correctness of the application design.

scholarly journals DYNAMICS OF TRACTION DEVICE OF MINE SUSPENDED MONOREL ROAD

2020 ◽  
Vol 12 (3) ◽  
pp. 410-417
Author(s):  
Viktor GUTAREVICH ◽  
◽  
Marina KONDRATENKO ◽  
Keyword(s):  
Mathematical Model ◽  
Mechanical System ◽  
Structural Parameters ◽  
Low Frequency ◽  
Dynamic Loads ◽  
Pressing Force ◽  
Negative Effect ◽  
Traction Device ◽  
The Difference ◽  
Fatigue Fractures

During the operation of the mine suspension monorail track and traction device form a mechanical system experiencing high dynamic loads associated with implementation of traction and braking forces. Emerging dynamic loads lead to formation of elastic deformations and oscillations that cause vibrations, which leads to displacement of drive wheels and reduces the implementation of traction. The study of the dynamics of traction device is an important step in improving safety and reliability of monorail transport. The aim of the work is to study dynamics of a friction-type traction device moving along a suspended monorail to assess influence of parameters of the elements of device on the vibrations and nature of interaction of drive wheels with monorail. Research methods. Mathematical modeling of the oscillatory processes resulting from interaction of the running gear of the traction device with the monorail is used. Stages of research include drawing up a design diagram oscillations of drive wheels of the traction device interacting with the monorail, developing a mathematical model for the analysis of vibrations caused by moving loads, also assessing the influence of structural parameters of mechanical system under consideration on nature of oscillations. Research results. The developed mathematical model of friction-type traction device movement allows us to establish relationship between parameters of structural elements of its running gear and pressure mechanism, as well as nature of vibrations that arise. As a result, frequencies of the mechanical system under consideration and maximum deviations were found, which allows you to set optimal device parameters to increase traction and increase lifespan of monorail suspended roads. Findings. It was determined that the frequency range of vibration of drive wheels mainly corresponds to the mid-frequency local vibrations of 16–36 Hz. Increasing length of lever for fixing axles of wheels and reducing their radius leads to formation of low-frequency vibrations with a frequency of less than 15 Hz. When length of lever of drive wheels is more than 0.5 m, shoulder of the spring is more than 0.6 m and radius of drive wheels is less than 0.25 m, vibrations with frequencies below 5 Hz can occur. It was found that increasing the length of lever for securing spring increases the oscillation frequency of one drive wheel and reduces frequency of the other. The difference between these frequencies significantly affects changes in the pressure of the wheels against monorail. When difference between frequencies is more than 10–12 Hz, direction of load changes pulsed, with a maximum swing of 0.02 rad, which reduces formation of fatigue fractures of tire wheels, and moments of decrease and increase in pressing force have a negative effect on traction, leading to slippage of drive wheels. When difference between frequencies is less than 10–12 Hz, direction of the load changes sharply, with a maximum swing of 0.03 rad, which increases deformation and formation of fatigue fractures of tire wheels, and short moments of weakening and increase of pressing force, constituting 0.1–0.3 s does not have a significant negative effect on traction.

scholarly journals Parametric Study on the Response of Composite Single Piles to Lateral Load by Numerical Simulation (FDM)

2018 ◽  
Vol 3 (10) ◽  
pp. 16-20
Author(s):  
Alex Otieno Owino ◽  
Zakaria Hossain ◽  
Jim Shiau
Keyword(s):  
Parametric Study ◽  
Primary Component ◽  
Critical Parameters ◽  
Foundation Design ◽  
Material Stiffness ◽  
Single Piles ◽  
The Difference ◽  
Lateral Behavior ◽  
Ultimate Loading Capacity ◽  
The Given

This paper entails a detailed numerical and parametric study on the lateral behavior of piles in foundation designs. Single-piles are one of the major components of a foundation as they act as the primary component in the transmission of the weights above the structure into the ground for stability to be attained. For this reason, a detailed study on the influence generated on the p-y curves is mandatory to create a numerically valid model for use in the process of foundation design without much ado. Modeling procedure under consideration employs the use of the finite difference method (FMD) embedded in FLAC2D. FDM is used to implement a solution to the coded input for example soil and pile element parameters. The model validation process done in this paper involves the variation of some of the critical parameters such as the variation on the type of soil in the area under consideration. Next, modification of the elastic modulus of the given soil as a check on the cohesiveness, change on the loading velocity at the top of the pile, a variation of the pile material stiffness and the difference of the pile eccentricity. The results obtained from the p-y curves generated from the parameters undergo sifting through for any effects on the ultimate loading capacity of the pile to the allowed design loading limits upon full structural installation. This variation is necessary for the approval of the validity of the model in engineering design. The parametric study from this study shows that the structure is of functional strength and a tolerable factor of safety.

Regeneration of Used Vacuum Pump Oil by Furfuryl Alcohol

2011 ◽  
Vol 361-363 ◽  
pp. 569-573
Author(s):  
Xiao Chao Yan ◽  
Zheng Zai Cheng ◽  
Rui Lei ◽  
Su Su Lin
Keyword(s):  
Refractive Index ◽  
Solvent Extraction ◽  
Furfuryl Alcohol ◽  
Viscosity Index ◽  
Vacuum Pump ◽  
Critical Parameters ◽  
Extraction Temperature ◽  
Refined Oil ◽  
The Difference ◽  
Solvent Extraction Technique

Solvent extraction technique is one of the cheapest and most efficient processes experienced in recycling of used lubricating oils. In this paper, the performance of furfuryl alcohol in recycling used vacuum pump oil was evaluated experimentally. The effect of the most critical parameters (solvent to oil ratio, and extraction temperature) was investigated. The results show that viscosity index and refractive index of refined oil was related to the solvent to oil ratio. Viscosity index and the refractive index come to a reasonable value at 90°C when solvent to oil ratio equal to 1.5. The difference of IR spectrum of the used vacuum pump oil and re-refined vacuum pump oil show that absorption peaks at 1745cm – 1 and 1160 cm – 1 disappeared after solvent extraction.

C-H···H-C interactions in organoammonium tetraphenylborates: another look at dihydrogen bonds

2003 ◽  
Vol 81 (6) ◽  
pp. 727-743 ◽  
Author(s):  
Katherine N Robertson ◽  
Osvald Knop ◽  
T Stanley Cameron
Keyword(s):  
Closed Shell ◽  
Relative Strength ◽  
Critical Parameters ◽  
Bond Critical Point ◽  
Dipole Interactions ◽  
Dihydrogen Bonds ◽  
Induced Dipole ◽  
Bond Topology ◽  
Multipole Refinement ◽  
The Difference

The crystal structures of the tetraphenylborates of the dabcoH+, guanidinium (MeCN solvate), and biguanidinium cations are shown to contain a variety of C-H···H-C dihydrogen (DB) bonds of nominally zero polarity, as well as a variety of N-H···N, C-H···N, N-H···Ph, and C-H···Ph hydrogen (HB) bonds. These intermolecular bonds have been characterized topologically after multipole refinement of the structures. The coexistence of the DBs and HBs in each of the structures makes it possible to establish their relative strength hierarchy. It also illustrates the importance of the DBs in satisfying the tendency of these structures to maximize the total intermolecular bonding engagement. To compare the above DBs with other DBs, the results of an extensive set of MP2/6-31G(d,p) calculations (supplied by I. Alkorta) were analyzed for reference correlations between the bond-critical parameters. Thus, for an X-H···H-Y bond, the difference Δε(H)m between the Mulliken charges on the H atoms in the uncomplexed X-H and H-Y components correlates quite well with the X-H···H-Y parameters and can be used for predicting the topological strength of an X-H···H-Y bond. The use of the difference Δε(H)c in the bond does not appear to change the correlation significantly; closer correlations are observed when the amount of charge transferred on formation of the H···H bond is used instead of Δε(H)m or Δε(H)c. Bonding interactions are obtained even between like or symmetry-related H atoms as a consequence of induced-dipole interactions, which accounts for the existence of the above intermolecular C-H···H-C bonds with d(H···H) = 2.18–2.57 Å, electron density at the bond-critical point of ~0.05–0.08 e/Å3, and a rough estimate of the H···H binding energy of ~1-5 kcal/mol. Examination of the bond-critical parameters of X-H···H-Y bonds also suggests a criterion of stability of these bonds with respect to the transition from non-shared (closed-shell) X-H···H-Y interaction to covalent (shared-shell) X···H-H···Y interaction. This transition appears to be discontinuous.Key words: bond-critical parameters, bond topology, dihydrogen bonds, hydrogen bonds, organoammonium tetraphenylborates.

Characterization of Epoxy-Functionalized Silsesquioxanes as Potential Underfill Encapsulants

1998 ◽  
Vol 519 ◽  
Author(s):  
E. K. Lin ◽  
C. R. Snyder ◽  
F. I. Mopsik ◽  
W. E. Wallace ◽  
W. L. Wu ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Flip Chip ◽  
Coefficient Of Thermal Expansion ◽  
Silica Particles ◽  
Critical Parameters ◽  
Organic Hybrid ◽  
Solder Bumps ◽  
The Difference ◽  
Electronics Packages

AbstractIn electronics packaging, underfill encapsulants are needed to improve package reliability in flip-chip devices. The underfill generally consists of an epoxy resin highly filled with silica particles and is designed to reduce the stress arising from the difference in the thermal expansion between the solder bumps and the substrate. Currently, concerns about the flow of the silica particles and surface phenomena are arising as electronics packages reduce in size. Newly developed epoxy-functionalized octameric silsesquioxanes provide an intriguing alternative to current formulations. These single-phase inorganic/organic hybrid materials may have properties similar to filled materials without the complications from the rheology of filled materials. The physical properties of the functionalized silsesquioxanes are measured with respect to the critical parameters for underfill materials. Measurements of properties such as the coefficient of thermal expansion and density are performed to evaluate the suitability of these materials as potential underfill encapsulants.

scholarly journals Thermal-optical analysis for the measurement of elemental carbon (EC) and organic carbon (OC) in ambient air a literature review

2015 ◽  
Vol 8 (9) ◽  
pp. 9649-9712 ◽  
Author(s):  
A. Karanasiou ◽  
M. C. Minguillón ◽  
M. Viana ◽  
A. Alastuey ◽  
J.-P. Putaud ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Literature Review ◽  
Elemental Carbon ◽  
Ambient Air ◽  
Correction Method ◽  
Total Carbon ◽  
Light Transmittance ◽  
Critical Parameters ◽  
Optical Analysis ◽  
The Difference

Abstract. Thermal-optical analysis is currently under consideration by the European standardization body (CEN) as the reference method to quantitatively determine organic carbon (OC) and elemental carbon (EC) in ambient air. This paper presents an overview of the critical parameters related to the thermal-optical analysis including thermal protocols, critical factors and interferences of the methods examined, method inter-comparisons, inter-laboratory exercises, biases and artifacts, and reference materials. The most commonly used thermal protocols include NIOSH-like, IMPROVE_A and EUSAAR_2 protocols either with light transmittance or reflectance correction for charring. All thermal evolution protocols are comparable for total carbon (TC) concentrations but the results vary significantly concerning OC and especially EC concentrations. Thermal protocols with a rather low peak temperature in the inert mode like IMPROVE_A and EUSAAR_2 tend to classify more carbon as EC compared to NIOSH-like protocols, while charring correction based on transmittance usually leads to smaller EC values compared to reflectance. The difference between reflectance and transmittance correction tends to be larger than the difference between different thermal protocols. Nevertheless, thermal protocols seem to correlate better when reflectance is used as charring correction method. The difference between EC values as determined by the different protocols is not only dependent on the optical pyrolysis correction method, but also on the chemical properties of the samples due to different contributions from various sources. The overall conclusion from this literature review is that it is not possible to identify the "best" thermal-optical protocol based on literature data only, although differences attributed to the methods have been quantified when possible.

Establishing Correlation between Leaf Spring Specifications and Camber Drop

2014 ◽  
Vol 660 ◽  
pp. 794-798
Author(s):  
Majdi Abdul Rani Ahmad ◽  
M.A. Mohamad Rozaidi ◽  
Sarat Chandra Dass ◽  
Srinivasa Rao Pedapati
Keyword(s):  
Mathematical Model ◽  
Regression Analysis ◽  
Processing Parameters ◽  
Automotive Application ◽  
Leaf Spring ◽  
Heavy Load ◽  
Spring Rate ◽  
The Difference ◽  
Gathering Data ◽  
Half Length

Manufacturing of leaf spring for automotive application to support heavy load vehicles such lorry and truck is a challenging process. This is due to the difficulty in fabricating the leaf spring exactly as per designed. The difference between the desired leaf spring shape and the actual fabricated shape is known as camber drop. The aim of this study is to establish the correlation between leaf spring specifications, camber drop and its processing parameters. The formulated equation can thus be used to predict the extent of camber drop and required action can be taken to reduce camber drop. This work was conducted by gathering data of variables suspected to influence camber drop, namely quenching camber, half-length of the spring, spring rate and end thickness of the spring. Regression analysis was conducted and the correlation between leaf spring’s specifications and camber drop is given. A mathematical model able to predict the extent of camber drop is formulated.

scholarly journals A review on the fused deposition modeling (FDM) 3D printing: Filament processing, materials, and printing parameters

2021 ◽  
Vol 11 (1) ◽  
pp. 639-649
Author(s):  
Ruben Bayu Kristiawan ◽  
Fitrian Imaduddin ◽  
Dody Ariawan ◽  
Ubaidillah ◽  
Zainal Arifin
Keyword(s):  
3D Printing ◽  
Manufacturing Process ◽  
Fused Deposition Modeling ◽  
Critical Parameters ◽  
Future Research ◽  
Printing Process ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
The Difference ◽  
Printing Parameters

Abstract This study aims to review research the progress on factors that affect the 3D printing results of the fused deposition modeling (FDM) process. The review is carried out by mapping critical parameters and characteristics determining FDM parameters, the effects of each parameter, and their interaction with other parameters. The study started from the filament manufacturing process, filament material types, and printing parameters of FDM techniques. The difference in each section has determined different parameters, and the respective relationships between parameters and other determinants during printing have a significant effect on printing results. This study also identifies several vital areas of previous and future research to optimize and characterize the critical parameters of the FDM printing process and FDM filament manufacturing.

RANCANGAN ALAT PEMOTONG PAVING KAPASITAS 275 POTONG/JAM DILENGKAPI PENGUKUR SUDUT

KOMPUTEK ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 79
Author(s):  
Bagus Hindarto ◽  
Fadelan Fadelan ◽  
Muhammad Malyadi
Keyword(s):  
Mechanical System ◽  
Angle Measurement ◽  
Time Difference ◽  
Long Time ◽  
The Difference ◽  
Time Required ◽  
Shape And Size

Implementation of a project there are three main aspects which is an indicator of the sustainability of cost, schedule and quality. The project succeeds when the time and cost of the implementation are as planned. One of them is paving installation project. The average paving cut process takes 90 seconds for 1 paving d using a cutting grinder. Disadvantages of cutting grinding is a long time, but it also causes dust and noisy sound, resulting from knife blades with paving. The current tool is not equipped with an angle meter, for cutting with a certain angle only forecasting only. The use of arcs manually takes a longer time.The purpose of this plan is to accelerate the process of cutting paving according to the shape and size of the Pav- ing cutting will be more efficient when equipped with angle measurement. The planning of this tool using a mechanical system, work by clamping the object to be cut and only one press for cutting 1 paving. The result of the planning of the paving cutter with angle engraver is ob- tained by the difference of cutting time for paved rectangular paved 15o, 30 °, 40 ° 45o each 81 seconds, 75 seconds, 75 seconds, 83 seconds time difference for paving rectangle with cut length 10cm and 20cm are respectively 66 seconds and 86 seconds while the time difference for paving the hexagon with a length of 160m and 22 cm is 72 seconds respectively and To sec. The average time required for each cutting ± 13 seconds cut. 

Sign in / Sign up

Export Citation Format

Share Document