scholarly journals Fluence of age factor on main strength and deformative properties of timber

2020 ◽  
pp. 35-41
Author(s):  
С.С. Гомон С.С.
Keyword(s):  
Experimental Studies ◽  
Solid Wood ◽  
Test Machine ◽  
Hydraulic Test ◽  
Coniferous Species ◽  
Deformation Parameters ◽  
Average Maximum ◽  
The Press ◽  
Strength And Deformation ◽  
Experimental Researches

The analysis of literature sources on this topic is carried out. It was found that the influence of age on the main strength and deformation parameters has not been studied. The method of experimental researches of coniferous and deciduous species of solid wood of different age at one-time short-term loading along fibers is resulted. To solve the problems, a series of samples of 1 sort of solid wood in the form of prisms with a cross section of 30x30x120 mm were made. The following species of wood were tested: coniferous species - larch, pine, spruce; deciduous - birch, alder, ash. The age of wood was 20, 40, 60 years. At the time of testing, the moisture was 12%. The humidity of the wood was controlled using a moisture meter MD-814. Experimental studies were performed on a servo-hydraulic test machine STM-100 under a rigid load regime (by increasing the displacements of the press plate of the test machine). Based on the obtained results, complete diagrams of deformation of deciduous (birch, alder, ash) and coniferous (larch, pine, spruce) species of solid wood at different ages (60, 40, 20 years) were constructed. The number of twin samples that were tested was 126 pieces. The main strength and deformation parameters were determined experimentally, in particular the average critical deformations of all studied wood species and the corresponding average maximum stresses. It is established that in the case of a rigid test regime, the deformation diagram of solid wood necessarily has two branches - ascending and descending. That is, the samples work in the so-called supercritical stage of work. It was found that the age of wood directly affects the strength and deformability of solid wood. In particular, with increasing age from 20 to 60 years, the strength and deformability of deciduous and coniferous species of solid wood increases significantly. Based on the test results, conclusions were drawn. Further research on this topic is highlighted.

scholarly journals Timber with improved strength and deformable properties

2020 ◽  
Vol 99 (3) ◽  
pp. 17-27
Author(s):  
P. Yasniy ◽  
S. Gomon
Keyword(s):  
Modulus Of Elasticity ◽  
Test Machine ◽  
Timber Species ◽  
Deep Processing ◽  
Coniferous Species ◽  
Initial Modulus ◽  
Experimental Researches ◽  
Maximum Stresses

The technique of experimental researches of solid timber modified by «SILOR» by surface and deep processing is given. Complete diagrams of deformation of unixial compression of deciduous and coniferous species of solid timber modified with «SILOR» under by surface and depth modification on modern test machine STM-100 are constructed. The initial module of elasticity and the secant module of deformation for such elements are determined. The influence of «SILOR» on the main strength and deformable properties of different timber species (maximum stresses, ultimate deformations, initial modulus of elasticity, secant module of deformation) is analyzed, the dynamics of their change is shown.

CALCULATION OSCILLATIONS OF VARIOUS ELEMENTS OF THE ELASTIC SYSTEM OF THE CENTER-FREE GRINDING MACHINE SASL 5AD

2020 ◽  
pp. 160-165
Author(s):  
Джугурян Т.Г. ◽  
Марчук В.І. ◽  
Марчук І. В.
Keyword(s):  
Horizontal Plane ◽  
Natural Frequencies ◽  
Elastic System ◽  
Experimental Studies ◽  
Piezoelectric Sensors ◽  
Forced Oscillations ◽  
Method Of Calculation ◽  
Vibration Resistance ◽  
Grinding Machine ◽  
Experimental Researches

During the design of operations of centerless intermittent grinding of surfaces there is a need to identify the natural frequencies of oscillations of the elements of the technological system of grinding. The method of calculation of rigidity, vibration resistance and forced oscillations of the elements of the circular grinding machine is offered in the article. Carrying out of experimental researches of rigidity of elastic system of the SASL 5AD grinding machine. We conducted preliminary experimental studies to measure the oscillations of various elements of the elastic system of the SASL 5AD grinding machine in the horizontal plane by piezoelectric sensors during grinding with continuous and discontinuous circles with different geometric parameters.

scholarly journals Experimental Studies on the Rheological and Hydraulic Performance of Palm Based Hydraulic Fluid

2014 ◽  
Vol 66 (3) ◽  
Author(s):  
W. B. Wan Nik ◽  
F. Zulkifli ◽  
S. S. Lam ◽  
M. M. Rahman ◽  
A. A. Yusof ◽  
...  
Keyword(s):  
Shear Rate ◽  
Palm Oil ◽  
Experimental Studies ◽  
Mechanical Efficiency ◽  
Hydraulic Performance ◽  
Pressure Increase ◽  
Major Influence ◽  
Hydraulic Fluid ◽  
Plant Oil ◽  
Hydraulic Test

Development of environmental friendly hydraulic fluid has a major influence in ecologically benign environment. The use of plant oil as hydraulic fluid would help to minimize hazardous pollution caused by accidental spillage, lower disposal costs of the used fluid and meet the environmental regulations. Hydraulic test rig was built to conduct endurance test where it can be operated continuously with several safety features. This research was conducted to evaluate the rheology elements and hydraulic performance of palm based hydraulic fluid. The palm oil shows decreasing trend in volumetric efficiency as the pressure increase while the mechanical efficiency increases as the pressure increase. Properties and characteristics of palm based hydraulic fluid were evaluated via rheology study. The effect of viscosity with temperature and shear rate was studied. The influence of shear rate and temperature on the variation of viscosity was clearly observed but temperature has more significant influence. Interpretations of rheological models indicate that this palm based hydraulic fluid belongs to pseudo-plastic category. Further analysis was done to fit the experimental data with two models and the findings show that Cross rheological model fits well with the experiment data. The plant oil was used in 1000 hours operation in a hydraulic system built in Universiti Malaysia Terengganu. The overall results suggest the potential substitution of palm oil as hydraulic fluid in marine applications.

scholarly journals The results of experimental studies of arable unit MTZ-82+PBS-3M

2019 ◽  
pp. 73-77
Author(s):  
Vasiliy Mihaylovich Boykov ◽  
Sergey Viktorovich Startsev ◽  
Aleksey Vladimirovich Ageev
Keyword(s):  
Experimental Studies ◽  
High Hardness ◽  
General Purpose ◽  
Low Humidity ◽  
Experimental Researches ◽  
Unit Performance

It is given the description of the design and specifications developed in Saratov State Agrarian University plow-blade grader of general purpose PBS-3M aggregated with tractors of traction class 1.4. In the result of experimental researches of the arable unit consisting of the MTZ-82 tractor and the plow PBS-3M on a stubble background of the field with soil of low humidity and high hardness operational and technological indicators of the unit on the main dump processing of the soil are defined.  Studies were conducted in three ways: plough PBS-3M fitted with three frames, fitted with two frames, with removed front frame; fitted with two frames, removed the rear frame. The graphical dependences of the plow traction resistance and the unit performance on the speed of MTZ-82+PBS-3M are presented.

Strength and Deformation of Combined Beams with Side Reinforced Plates

2019 ◽  
Vol 968 ◽  
pp. 234-239
Author(s):  
Talyat Azizov ◽  
Oleksii Melnik ◽  
Oleksandr Myza
Keyword(s):  
Experimental Data ◽  
Reinforced Concrete ◽  
Experimental Studies ◽  
Calculated Data ◽  
Concrete Plate ◽  
Combined Action ◽  
Strength And Deformation ◽  
Concrete Plates ◽  
Good Agreement

The results of experimental studies of combined beams consisting of a stone part, reinforced with side reinforced concrete plates are given. Experimentally shown the viability of the proposed structures. The conditions for ensuring the combined action of a stone beam and a reinforced concrete plate are given. Cases are shown when one-sided plates can be used and when double-sided reinforced concrete plates can be used. A comparison of experimental data with the data calculated by the authors developed methods is given. A good agreement between theoretical and calculated data is shown.

scholarly journals Experimental studies of combined coulter for direct strip sowing of seeds

2019 ◽  
Vol 298 ◽  
pp. 00140 ◽  
Author(s):  
Oleg Pisarev ◽  
Maksim Moskovskiy ◽  
Aleksey Dorockhov ◽  
Anatoly Gulyaev ◽  
Aleksandr Lavrov
Keyword(s):  
High Speed ◽  
Experimental Studies ◽  
Particle Movement ◽  
Experimental Researches ◽  
Direct Sowing

In the paper It is presented the results of experimental researches about determination of the main parameters of the seed distributer of the combined coulter for direct sowing of seeds at the installation for high-speed stroboscopic photography of particle movement.

Contact Stress, Frictional Torque and Lubrication in Articulating Pin Joints

2007 ◽  
Author(s):  
R. S. Dwyer-Joyce ◽  
A. Beke
Keyword(s):  
Stress Distribution ◽  
Contact Stress ◽  
Angular Displacement ◽  
Ultrasonic Method ◽  
Static Friction ◽  
Frictional Torque ◽  
Test Machine ◽  
Hydraulic Test ◽  
Joint Rotation ◽  
Contact Stress Distribution

Pin joints are used in many items of industrial machinery where two structural members are required to articulate. A pin is assembled between typically four bushes. As the members articulate the pin rotates relatively slowly inside the bushes. A hydraulic test machine has been developed to load and articulate a 56 mm diameter pin held in four bushes, typical of that found in earth moving machinery and aircraft landing gear. The rig is capable of applying realistic loads and speeds of articulation, whilst measuring torque and angular displacement. The test machine design and operation is described. The pin joint is lubricated with mineral oil based grease. Joint rotation is relatively slow and hydrodynamic calculations predict that the joint operates in the boundary regime. During a single cycle the torque remains largely constant, with a static friction peak at the beginning and end of the cycle. Measurements of the torque during articulation demonstrate friction coefficients varying from 0.02 to 0.12 depending on the rotational speed. The contact stress distribution between the pin and bushes was estimated by an ultrasonic method. An ultrasonic pulse was sent through the hollow pin and reflected back from the pin-bush interface. High contact pressures causes conformity between the pin and bush and so the wave passes through. The proportion of the sound wave reflected was used to estimate the contact stress distribution. The results showed how the stress is maximum in the outer bushes and over a 60° arc of the pin. The results of the study can be used to understand how pin joints function and how they may be optimised.

scholarly journals Fracture and Fatigue of Titanium Narrow Dental Implants: New Trends in Order to Improve the Mechanical Response

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3728 ◽  
Author(s):  
Eugenio Velasco-Ortega ◽  
Antonio Flichy-Fernández ◽  
Miquel Punset ◽  
Alvaro Jiménez-Guerra ◽  
José María Manero ◽  
...  
Keyword(s):  
Fatigue Limit ◽  
Dental Implants ◽  
Mechanical Response ◽  
Pure Titanium ◽  
Test Machine ◽  
Commercially Pure Titanium ◽  
Hydraulic Test ◽  
Mechanical Cycling ◽  
Cp Ti

Sixty-four fractured commercially pure titanium (cp-Ti) narrow dental implants (NDIs) with similar macrogeometry and connection designs were studied after different implantation times in humans in order to determine their reliability and to evaluate the causes of the fracture. These NDIs were compared with other similar implants, made with alloyed titanium with 15% Zr and with 12% strained titanium. Original implants were tested under static and fatigue conditions, simulating the tri-axial loads in the mouth by means of a Bionix hydraulic test machine. Fractography was studied using field-emission scanning electron microscopy (FSEM). The results showed that cp-Ti NDI exhibits low strength for mechanical cycling, and the alloyed Ti and strained titanium increase the mechanical strength, guaranteeing long term mechanical behavior. NDIs fractured due to fatigue, and, in some cases, the presence of cracks in the original NDIs quickly led to fracture. These cracks were attributed to plastic deformation during machining were found to be exacerbated due to acid etching in the passivation process. All cases of fracture were cp-Ti dental implants due to the low fatigue limit. The results show that, when titanium is alloyed or cold-worked, the fatigue limit is higher than cp-Ti. This in vitro research will help clinicians to select a better NDI system for safer treatment.

Sign in / Sign up

Export Citation Format

Share Document