scholarly journals Reconditioning and hardening of mining equipment hydraulic cylinder working surfaces by using of double-electrode cladding

Author(s):  
S I Zverev ◽  
A M Fiveyskii
2019 ◽  
Vol 14 (4) ◽  
pp. 424-429 ◽  
Author(s):  
Ying Zhang ◽  
Liangcai Zeng ◽  
Zhenpeng Wu ◽  
Xianzhong Ding ◽  
Kuisheng Chen

2020 ◽  
Vol 140 (3) ◽  
pp. 320-325
Author(s):  
Yoshihiro Ohnishi ◽  
Takahisa Shigematsu ◽  
Takuma Kawai ◽  
Shinichi Kawamura ◽  
Noboru Oda

Author(s):  
A. D. Terenteva

In civil engineering in Russia, trenching for utilities is currently under digging. To perform such works, it is necessary to use high-precision construction machinery, because inaccurate performance of works can lead to the break down of existing utilities, thereby affecting the residents of nearby houses and demanding the additional works for renewal.The most universal labour saver to perform construction works is hydraulic driven single-bucket excavators, which provide up to 38% of works. Therefore, to improve technical characteristics that affect the accuracy of the work performed is an important task.High requirements for the performance of works are defined by existing construction regulations: an allowable soil layer to remain is at most 0.05 m. To fulfil such requirements, an exact assessment of the working mechanism position and a trench profile is necessary.Examination of a manually operated digging process shows that an operator provides operations untimely, however an automated control system can solve this problem. Dynamic phenomena in the working mechanism have the greatest impact on the accuracy of the works performed.To assess the bucket digging edge position accuracy, a mathematical model of the working mechanism has been created. Based on the cycle scheme of the working process, the excessive displacements of the hydraulic cylinder rods under the load are taken into account. By the end of the cycle, the difference between the specified and obtained positions along the vertical coordinate has been 0.0892 m.A dynamic error of the hydraulic drive system of the working mechanism is considered as a sum of the error due to excessive displacements of the hydraulic cylinder rods and the error due to delay of the hydraulic drive, with the latter being calculated for the average time of delay taking into account the data available in the literature. The total error of the bucket digging edge position of the working mechanism is 0.1176 m, which is 2 times more than the value of 0.05 mConformity of all the links with specification requirements does not guarantee compliance with the required displacement accuracy of the bucket digging edge, and, thus, the soil layer to remain in the base of the trench can exceed the regulated value of 0.05 m.


Author(s):  
A.F. Klebanov ◽  
M.V. Kadochnikov ◽  
V.V. Ulitin ◽  
D.N. Sizemov

The article addresses the issues of ensuring safe operation of mining equipment in surface mining. It describes the main factors and situations that pose a high risk to human life and health. The most dangerous incidents are shown to be related to limited visibility and blind spots for operators of mining equipment, which can result in collisions and personnel run over. The main technologies and specific solutions used to design collision avoidance systems are described and their general comparison is provided. A particular focus is placed on monitoring the health of employees at their workplace by means of portable personal devices that promptly inform the dispatcher of emergency situations. General technical requirements are formulated for designing of the system to prevent equipment collisions and personnel run over in surface mining operations. The paper emphasizes the importance of introducing a multifunctional safety system in surface mines in order to minimise the possibility of incidents and accidents throughout the entire production cycle.


Alloy Digest ◽  
1983 ◽  
Vol 32 (8) ◽  

Abstract TRI-MARK TM-115 is a gas-shielded flux-cored welding electrode for continuous high deposition are welding. It is designed specifically for semiautomatic and automatic arc welding of high-strength low-alloy steels and quenched-and-tempered steels. This gas-sheilded tubular wire can be used for single and multiple-pass welding. It has outstanding low-temperature impact properties. Its applications including mining equipment, large vehicles and similar items. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as heat treating, machining, and joining. Filing Code: SA-392. Producer or source: Tri-Mark Inc..


2020 ◽  
pp. 252-255
Author(s):  
V.I. Bolobov ◽  
V.S. Bochkov ◽  
E.V. Akhmerov ◽  
V.A. Plashchinsky ◽  
E.A. Krivokrisenko E.A.

On the example of Hadfield steel, as the most common material of fast-wearing parts of mining equipment, the effect of surface hardening by plastic deformation on their impact and abrasive wear resistance is considered. Wear test is conducted on magnetic ironstone as typical representative of abrasive and hard rock. As result of wear of initial samples with hardness of ∼200 HB and samples pre-hardened with different intensities to the hardness of 300, 337 and 368 HB, it is found that during the initial testing period, the initial samples pass the “self-cold-work hardening” stage with increase in hardness to ∼250 HB, which remains virtually unchanged during further tests; the hardness of the pre-hardened samples does not change significantly throughout the tests. It is established that the rate of impact-abrasive wear of pre-hardened samples is significantly (up to 1.4 times) lower than the original ones that are not subjected to plastic deformation, and decreases with increasing degree of cold-work hardening. Preliminary surface hardening by plastic deformation can serve as effective way to increase the service life of fast-wearing working parts of mining equipment.


Sign in / Sign up

Export Citation Format

Share Document