scholarly journals EXPEDIENCY OF USING FRICTION-BEARING ASBESTOS-RUBBER MATERIALS IN FRICTION UNITS

2021 ◽  
Vol 4 (4) ◽  
pp. 89-93
Author(s):  
Leonid Kondratev ◽  
Nikolai Jujukin

The article presents an analysis and comparison of friction elements consisting of Ferodo and retinax with asbestos-rubber friction material 143-63 and 8-45-62 in the nodes and brakes of forging and pressing machines operated at the factories of the forest and woodworking industry. In Russia, widely used friction materials Ferodo and retinax in the clutches and brakes of operating machines no longer satisfy consumers in many cases due to their low strength and wear resistance, which began to limit the performance of friction units. The analysis showed that the use of friction asbestos-rubber materials of grades 143-63 and 8-45-62 in the nodes and brakes of forging and pressing machines operated at the factories of the forest and woodworking industry, will dramatically increase both the productivity of machines and their performance, and also makes it possible to significantly reduce the cost of maintenance and repair of forging and pressing equipment.

2011 ◽  
Vol 311-313 ◽  
pp. 473-476
Author(s):  
Jian Hua Du ◽  
Jian Guo Han ◽  
Cheng Fa Xu

The Cu-based friction materials with nano-AlN (n-AlN) and nano-graphite (n-C) were prepared by powder metallurgy technology, respectively. The microstructures and friction performance were studied through scanning electron microscope (SEM) and friction tester rig, respectively. The results indicate that the n-AlN and n-C particles can enhance the properties of Cu-based friction materials remarkably. Compared with the friction materials without any nanometer materials, the wear resistance of the friction materials with n-AlN and n-C has been improved by 25 % and 11 %, respectively. The heat resistance of the materials with n-AlN and n-C has been improved 18 % and 25 %, respectively. The n-AlN and n-C particles can reduce the abrasive wear and enhance the wear resistance of the Cu-based friction materials.


2011 ◽  
Vol 694 ◽  
pp. 413-417
Author(s):  
Jian Hua Du ◽  
Yan Zang ◽  
Xiao Ying Zhu

The Cu-based friction materials with nano-AlN (n-AlN) particles were prepared by powder metallurgy technology. The friction performance of the friction materials was investigated through test rig. The microstructure and worn morphology were studied through scanning electron microscopy (SEM). The results indicate that the coefficient of the Cu-based friction materials with 0.75 wt % n-AlN is high and stable. Comparing with the traditional friction materials without n-AlN, the wear resistance and heat resistance of the friction materials with n-AlN has been improved by 25 % and 18 %, respectively. The n-AlN particles can reduced the abrasive wear and enhance the wear resistance of the Cu-based friction materials.


2011 ◽  
Vol 284-286 ◽  
pp. 905-908 ◽  
Author(s):  
Jian Hua Du ◽  
Yuan Yuan Li ◽  
Xiao Hui Zheng

The Cu-based friction materials with nano-graphite were prepared through powder metallurgy technology. The microstructure and friction performance were studied through scan electronic microscope (SEM) and friction tester, respectively. The results indicate that coefficient of the Cu-based friction materials with 2 wt% nano-graphite is high and stable. Comparing with the friction materials without n-C, the wear resistance and heat resistance of the friction materials with nano-graphite has been improved by 11 % and 25 %, respectively. The nano-graphite particles will reduce the abrasive wear and enhance the wear resistance of the Cu-based friction materials.


2021 ◽  
Vol 871 ◽  
pp. 170-175
Author(s):  
Hao Li ◽  
Bo He

To prepare a kind of Fe-Cu-based friction material with good friction performance and wear resistance, and apply it to the brake structure of automobile machinery, the powder metallurgy method is used to prepare the friction materials in the standard with 4% Ni, 4% Mo and 2% Sn as the auxiliary material, SiC, Al2O3, and zircon sand as the basic friction material, 8% graphite and 3% MoS2 as the lubricating component. Meanwhile, 50% Fe and 20% Cu is used for the preparation of friction materials. The friction and wear resistance can be increased by increasing the carbon fiber content of 0-8% concentration of the material. The results show that the friction coefficient of the Fe-Cu-based friction material is relatively gentle after the addition of 2% carbon fiber, and the compactness peaks, reaching 93.3%. Its shear strength and impact strength peak, which are 37.42Mpa and 6.7J/cm2 respectively. 4% carbon fiber material with a hardness of 120.2 HV is the hardest one, followed by 2% carbon fiber material with a hardness of 118.1 HV. Added with 2% carbon fiber, the abrasion amount of the friction-based material is 0.0027 g at room temperature and-0.0008 g at 400°C after 60 minutes respectively. With all indicators considered, the result shows that the friction performance and wear resistance of Fe-Cu-based friction materials can be increased by adding 2% carbon fiber during the preparation of basic friction materials.


2021 ◽  
Vol 20 (4) ◽  
pp. 345-351
Author(s):  
A. V. Liashok ◽  
Yu. B. Popova

Sintered friction materials are widely used in friction units of automotive vehicles and special purpose vehicles.  The main purpose is to transmit torque to the actuator. The development of the technology market requires the development and use of new units. At the same time, the creation of new materials is required, which also applies to sintered friction materials. This group of materials is characterized by a high service life, efficiency of torque transmission, as well as the ability to restore performance in case of violation of operating modes. One of the most significant parameters characterizing  a sintered friction material is wear resistance. In most cases, it determines not only the resource of the unit itself, but the entire machine as a whole. A special place is occupied by brake units, which also use friction materials. The increased wear  resistance of the friction material contributes to a decrease in the efficiency and service life of the brake system. Evaluation  of the wear resistance of a friction material for the given operational parameters is a very long and costly process. The development of methodology and methods for accelerating the assessment of wear resistance is an important scientific and practical task. The paper presents the results of using artificial neural networks to predict the service life of a composite friction material based on copper on the sliding speed, pressure on the material and the amount of lubricant supplied to the friction zone. An artificial neural network has been trained using an array of experimental data for the FM-15 friction material.  The training results have shown high accuracy, correctness of the proposed and implemented network architecture. The developed software has demonstrated its efficiency and the possibility of using it in calculations to determine the wear of a composite friction material.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 567
Author(s):  
Anun Wongpayakyotin ◽  
Chanchira Jubsilp ◽  
Sunan Tiptipakorn ◽  
Phattarin Mora ◽  
Christopher W. Bielawski ◽  
...  

A series of substituted polybenzoxazines was synthesized and studied as binders in non-asbestos friction composite materials. The structures of the polybenzoxazines were varied in a systemic fashion by increasing the number and position of pendant alkyl (methyl) groups and was accomplished using the respective aromatic amines during the polymer synthesis step. By investigating the key thermomechanical and tribological characteristics displayed by the composite materials, the underlying structure-properties relationships were deconvoluted. Composite friction materials with higher thermomechanical and wear resistance properties were obtained from polybenzoxazines with relatively high crosslink densities. In contrast, polybenzoxazines with relatively low crosslink densities afforded composite friction materials with an improved coefficient of friction values and specific wear rates.


2021 ◽  
Vol 04 (1) ◽  
pp. 54-54
Author(s):  
V. R. Nigmatullin ◽  
◽  
I. R. Nigmatullin ◽  
R. G. Nigmatullin ◽  
A.M. Migranov ◽  
...  

Currently, to increase the efficiency of industrial production, high-performance and expensive technological equipment is increasingly used, in which the weakest link, from the point of view of efficiency and reliability, is the components and parts of heavily loaded tribo – couplings operating both at significantly different temperatures (conditionally under lighter conditions, the temperature difference can be 100-120 degrees) and climatic conditions (high humidity, the presence of abrasives and other chemical elements in the atmosphere). As the results of the analysis of the frequency of failures of friction units and, accordingly, the cost of their restoration reach 9-20 percent of the cost of all equipment, without taking into account significant losses of income (profit) of the enterprise from downtime. The solution of this problem is based on the study of the wear rate of friction units by the wear products accumulated in working oils, cooling lubricants, and greases. A digital equipment monitoring system (DSMT) has been developed and implemented, which includes dynamic recording of the number of wear products and oil temperature by original modern recording devices, followed by the technology of their processing and use. The system also includes methods for finding the necessary information in large data sets useful and necessary in theoretical and practical terms with a similar technique controlled by a digital monitoring system. The advantages of SMT are the ability to predict the reliability of the equipment; reduce production risks and significantly reduce inefficient costs.


2018 ◽  
Vol 1150 ◽  
pp. 22-42
Author(s):  
Dinesh Shinde ◽  
Kishore N. Mistry ◽  
Suyog Jhavar ◽  
Sunil Pathak

The peculiar feature of friction materials to absorb the kinetic energy of rotating wheels of an automobile to control the speed makes them remarkable in automobile field. The regulation of speed cannot be achieved with the use of single phase material as a friction material. Consequently, the friction material should be comprised of composite materials which consist of several ingredients. Incidentally, the friction materials were formulated with friction modifier, binders, fillers and reinforcements. Due to its pleasant physical properties, asbestos was being used as a filler. Past few decades, it is found that asbestos causes dangerous cancer to its inhaler, which provides a scope its replacement. Several attempts have been made to find an alternative to the hazardous asbestos. The efforts made by different researchers for the impact of every composition of composite friction material in the field are reviewed and studied for their effect on the properties of friction material. Surface morphological studies of different friction material are compared to interpret the concept of surface wear and its correlation with material properties.


2021 ◽  
Vol 303 ◽  
pp. 01005
Author(s):  
Dmitry Lubyanoi ◽  
Evgeny Pudov ◽  
Evgeny Kuzin ◽  
Olga Semenova

The article shows the relevance of the use of alloyed cast iron in mining and metallurgical engineering. The article discusses the technologies for producing naturally alloyed cast iron. For working bodies and friction units of mining machines, such as pumps, coal pumps, hydrocyclones, crushers and mills. The main type of wear for them is abrasive. To increase the wear resistance of cast iron the production of cast iron has not been sufficiently studied yet. Although the use of cast iron in a complex alloyed with manganese, silicon, chromium, titanium and vanadium has been studied. The article studies the influence of manganese, titanium and vanadium on the mechanical properties and performance of machine parts and products of mining and metallurgical production in contact with high-temperature and highly abrasive media. The rational content of titanium and vanadium in gray cast irons is established in the range of 0.05-0.1%, which ensures their heat resistance and increases their wear resistance. The content of these elements can be increased to 0.07-0.12%. Bushings made of this cast iron have the required wear resistance and can increase the operational reliability of the equipment in the conditions of mining and metallurgical production. They also replace non-ferrous metals, as well as products obtained by powder metallurgy methods.


Author(s):  
L. I. Kovalyev ◽  
I. L. Kovalyev ◽  
M. N. Kostomakhin

Maintenance and repair of livestock machinery and equipment is carried out as a rule by specialized repair and service enterprises on the basis of service contracts in accordance with the procedure established by law. However, with the renewal of the park’s farms with machines and equipment with automated and computerized process control, as well as the reconstruction of dairy farms and complexes, it became necessary to have a production base and highly qualified specialists for the maintenance of equipment. The most important and key provisions of the improved methodology of planning and accounting of work in the technical service of animal husbandry with the use of a number of standards are given, some features of accounting and planning of these types of work have been noted. The concepts of “repair unit” and “category of complexity of technical service” have been defined. The general provisions of the methodology for calculating costs and determining the cost of carrying out maintenance and repair of livestock equipment have been considered. On the base of calculations, the average total cost standards for carrying out maintenance and repair of livestock equipment have been established. These standards greatly simplify the planning of costs during the operation of equipment, and also allow us to determine the cost of maintenance and repair at different stages of the creation of new machines.


Sign in / Sign up

Export Citation Format

Share Document