Welding steel core conveyor without destroying the use and breaking experimental workshop
Vulcanization process conveyor belt joint vulcanization process if careless operation, so that a row of wire rope in some good has not been cured, the adhesive surface in the
course of aging early fatigue failure in bending, tensile stress, they may be first with the conveyor belt pumping off body slip occurs, resulting in lost
Belt body with some rope excessive force and tear occurs rope body twitching or fracture phenomena, the joint strength. In short, the curing process is the conveyor belt joint
merits another critical factor.
Once breaking test in order to further clarify the rope to pull off with the belt surface in the process of change and gradually extended break phenomenon in coal mining in
Telescopic belt conveyor
Materials Science Research Center conducted experiments to pull off tests. Vulcanized belt fitting parameters to be tested a complete connection
Head, the overall bandwidth of 1000mm, test section length 3800mm, fitting part of the length 2m, Conveyor Belt Model GX1000, the first lap Ⅱ kind of way, each of the upper and
lower cladding layer thickness 8mm.
Test (a) sample processing. The conveyor belt joint cut four equal width, followed by No. 1,2,3,4 in every belt with white paint draw squares, respectively, once breaking test. gravity conveyor
Treated samples as shown. (2) test system. In order to have
Effectively the development process of observation and analysis of the deformation of the belt surface in the center of the original experimental test bed material, based on the
layout of the three camera points. Test system layout is shown schematically.
Tensile test results and analysis of the phenomenon when the force to a certain value, the grid distortion occurs, and this deformation not begun to produce the same along the
entire cross-section with the deformation, but away from the belt edge occurs first 1/4 at the maximum deformation. This phenomenon will develop a
Belt-line detector for the apparent position of judge of the sensor is installed to provide experimental basis.
Pull off the conveyor belt to pull off the phenomenon of four cases are not identical. No. l belt is pulled, the outside connector is not broken, but the Rally of no force,
stating that snagging. The 2nd belt stretched 105mm, Rally stopped, rope off the six, but the conveyor belt joint is not broken. The 3rd delivery
Band stretched to 120mm, the conveyor belt from the middle fracture, broken away at the joints 320mm, part of the rope breaking, while part of the snag. The 4th belt pulled up
to 100mm, the middle one first off a rope, and the remaining snagging. You can see the main reason for steel cord conveyor belt breakage is sulfur
Of rope and belt bonded joints bad, and snag phenomenon (rope and belt out), because rope connectors are not accurate arrangement, can not be completely clean, so not every rope
after the force are subject to The same power, but a small number of force, resulting in a spinning is
Elephant. Once the small rope spinning, the strength is reduced so that the whole conveyor belt, resulting in fracture.
Analysis of test results can be seen from the test report single, four samples of the maximum intensity difference 100kN, i.e. the strength of Sample No. 2 Sample No. 3 75%,
which means that only one joint at the same vulcanization process , the intensity also vary so widely, it is difficult to achieve a conveyor belt
Different strength of the joint will remain almost the same intensity. While this is only one state in the test tensile breaking more than a conveyor belt in the long term by
using a fixed initial tension and various alternating stress fatigue damage arising from the situation. Thus in accordance with the strength of 70%
And 80% to set the prediction before breaking limit is not reliable.
It can be seen from the, the experimental conditions in terms of a stretch breaking, each belt have appeared and increased tensile elongation to maintain nearly horizontal state
phenomenon. Pull the belt at the beginning, the force and displacement have similar elasticity Hooke's law has the slope, but the period of
Curves are slightly bent downwardly, when the tension increased to a certain degree, a sudden change in the slope, the conveyor belt not immediately brittle fracture, but at a
certain force, the rapid increase in the elongation process. The connector has a characteristic before breaking, the polymer is a rubber material
Rheological phenomena. Can be carried out accordingly before breaking forecasts.
Conclusions Through the course of their work interfaces belt damage cause analysis, and after a stretch on the conveyor interface breaking experiment, you can get the following
four important conclusions: (1) conveyor interfaces during stretching from the edge 1 / 4 maximum deformation, for the introduction of an apparent deformation
Determine the interface destruction found a sensitive test target location, where you can add sensors. (2) before fracture belt interfaces obvious rheological phenomena, which
break the forecast for the interface to find a critical point. (3) by the percentage to predict fracture strength is not reliable
, Should rheological scaling percentage point forecast. (4) fatigue damage is broken belt interface, the main reason for the work process.