Excavator Bucket Teeth Research Articles

About Increasing Wear Resistance of Rock-Breaking Tool to Abrasion by Using Mechanical and Thermo-Mechanical Treatment

The experimental studies results of the mechanical and thermo-mechanical treatment influence of wear resistance of excavator bucket tooth materials and rotary cutting tool are presented in this article. Experiments on abrasion in different rocks were investigated. In the example of 110G13L steel (Hadfield steel), it was shown that mechanical strengthening (cold hardening) is an effective way to improve wear resistance of machine parts working in abrasive environments. It was revealed that if the hardness of abrasive materials is lower than the hardness of cold hardening steel, wear resistance may increase by 10 times and if the hardness of abrasive materials is higher than the hardness of steel with cold hardening, it does not influence wear resistance. It was found that the high-temperature thermo-mechanical treatment of 30KhGSA steel increases its hardness (by 23%) and wear resistance (by 38%) by comparing with the same steel after hardening. It was concluded that the advisable use one of these methods depends on rock hardness.

Kinematic Analysis of Hydraulic Excavator Working Device Based on D-H Method

To accurately describe the problem of excavator bucket teeth space trajectory in the mining process, is presented to describe the trajectory of excavator bucket teeth using D-H homogeneous coordinate method. Based on the principle of robotics, the excavator boom arm and bucket as three robot manipulators, through the driving of the boom cylinder and the arm cylinder and bucket cylinder, establish mathematical model of excavator working device pose space, using MATLAB/Simulink simulation to analyze the spatial motion, and fast get excavator mining envelope graph. The ZE-360 hydraulic excavator as an example, verify the scientific D-H homogeneous coordinate method in spatial motion analysis of excavator working device and adaptability, and provide a theoretical basis for the excavator trajectory and work space analysis.

Comparative Analysis of Wear for Excavator Bucket Tooth Using Different Materials

Comparative Analysis of Wear for Excavator Bucket Tooth Using Different Materials

Designing a system for measuring the flow of material transported on belts using ultrasonic sensors

Excavation tailings (scraping) and extracting the useful (lignite) in surface mine pits in Mining Basin Oltenia is achieved with technological lines of excavation - transport - dump of high productivity. A correlation of working capacity of the main components of technological lines (motor rotor, high capacity transport, car dumps) is necessary for economic reasons on electricity consumption. To achieve experience in the process was chosen excavator SRS 1400 from South Jilt career in the CET Turceni. The question of coal excavated volume has a great importance in the mine pits. At the excavation is desired a density estimate for each machine production tracking, cost estimation and tracking product unit profitability of each band on various sections zones. Permanent display size excavated volume snapshots in the excavator's cabin permits to track tape loading, eliminating unproductive times and information management to determine profitability. Another important requirement is closing the loop of the machine drive system of an excavator for a uniform deposition of carbon on the strip, thus achieving automatic control of the loading belt. Such equipment is important for the system dispatching in surface mine pits. Through a system of three ultrasound transducers to determine the smart instant of coal excavated section which, coupled with the tape speed, integrated over time will determine the amount of excavated coal. The basis of the system developed is a device for determining the volume and quantity of coal excavated acting on the march and optimize the system speed excavator working order. The device is designed primarily following the careers of lignite production: rotor excavators, rubber conveyor belts and dump facilities. Newly developed system aims to achieve the following determines: the optimum energy excavation depending on the nature of excavated material - lignite, shale, clay, etc., economic times to use the excavator bucket teeth rotor, energy optical regime to rubber belt conveyors, eliminate damage to the plant by conveyor belt breakage detection or tread and eliminating time and energy losses by limiting reproductive idle, monitoring the amount of coal excavated, control power consumption. Systems in general and particularly automated systems cannot be designed without taking into account their degree of effectiveness, compliance with minimum consumption of time, energy and materials, insofar as they are requested and used all the resources it has, at minimum cost production, etc. For this reason any matter of calculation, design, analysis and operation of transport systems continuously subordinate requirements optimality.

Wear Behavior of Weld Overlays on Excavator Bucket Teeth

An excavator is a typical hydraulic heavy-duty human-operated earth engaging machine tool used in general as a continuous digging machine in large-scale open pit mining operations. However, under dynamic loading, excavator bucket teeth are subjected to severe abrasive wear. The objective of this work was to improve the service life of the excavator bucket teeth in order to decrease the idle time required to reinstate the teeth periodically during excavation. This objective was carried out by overlaying the excavator bucket teeth (of high tensile steel) with four different wear resistant hardfacing alloys by manual metal arc welding. Comparative wear tests on a regular tooth and overlayed excavator bucket teeth were conducted in the field and laboratory (ASTM G-99, pin-on-disc apparatus), where the effect of hardfacing alloys on the extent of wear and the wear characteristics of the excavator teeth were examined.

Numerical Analyses of the Stress and Limiting Load for Buried Gas Pipelines under Excavation Machine Impact

This paper investigates buried gas pipelines impacted by an excavator bucket, in addition to the digging load driven by the hydrocylinder of an excavator, and the impact caused by liquid pressure oscillation and the inertial force of the excavator system. These were taken into account for the impact load subjected by the excavator bucket teeth, and the dynamic load coefficient was suggested theoretically. Then the dynamic stress distribution of the buried gas pipeline and corresponding digging limiting load were evaluated by using the strength criterion and the LS-DYNA commercial finite-element software, in which two excavation sections of perpendicular to and parallel to the longitudinal direction of pipeline were detected respectively. Furthermore, cracks exist in the actual pipeline, and the numerical analysis model of the high-pressure gas pipeline with an elliptical crack at the inner surface was established. The limit digging load while the crack existed was determined by the theory of dynamic fracture and compound fracture criterion, which was 20% lower than that without cracks. The numerical analysis method in this article has certain reference value to the design, construction, and risk assessment of a buried gas pipeline.

Investigation and application of high strength low alloy wear resistant cast steel

<title/>A kind of low alloy wear resistant cast steel that does not contain costly alloy elements such as molybdenum, nickel, copper and vanadium has been successfully developed. By the refinement with rare earth and titanium, the purification with blowing argon and improving the hardenability with boron, the cast steel containing 0·25-0·45%C, 0·5-1·5%Si, 0·5-1·5%Mn, 0·5-1·5%Cr and a small quantity of titanium, boron, rare earth, calcium and aluminium has high tensile strength, impact and fracture toughness and excellent wear resistance. In the excavator bucket teeth, crusher hammer and ball mill liner, low alloy wear resistant cast steel has 2-4 times longer servicing life than that of Hadfield austenitic steel, and its production cost is equal to that of Hadfield austenitic steel. The use of low alloy wear resistant cast steel is safe and reliable, and there is no fracture and scaling in the use. The application of low alloy wear resistant cast steel has good economic and social benefits.

Experimental puncture loads for external interference of pipelines by excavator equipment

A series of puncture experiments is presented for penetration of steel pipelines by excavator bucket teeth. Static puncture forces are obtained for pipes of 4.8–6.9 mm wall thickness, for a variety of different tooth geometries; primarily small cross-section or sharp tooth types have been used. Experimental results for varying tooth orientations are also presented. The results are compared against finite element simulations of the problem and against previously derived puncture relationships. The experiments provide good verification for the use of a simple puncture force equation that can be used for pipeline risk assessment purposes.

Prediction of gouging abrasion resistance of steel by pendulum grooving and other laboratory test methods

A comparative investigation is made of different laboratory test methods with respect to their ability to guide in the selection of materials resistant to gouging abrasive wear. The evaluation is based on the wear of excavator bucket teeth during loading of wet blast stone. Five different steel grades were included, ranging from quenched and tempered carbon steel to tool steel. The specific energy consumption during single-pass pendulum grooving proved to give the best correlation with the field test. It was also found that the pendulum test produced friction layers typical of gouging abrasion. Among the test materials a 5.3 wt.% Cr tool steel proved to have the best wear resistance followed by a quenched and tempered carbon steel grade.