methods of heightening of reliability of details from high-resistance steels
In transport machine industry for the purpose of heightening of a resource of details for a long time otdelochno-uprochnjajushchjaja handling [69, 126], in particular, surface plastic deformation (IID) also is successfully used.
Virtues IID:
- At handling of details, besides surface furnish there is a blanket hardening that allows not to disturb a filament of metal and promotes formation of fine-grained structure of metal;
- Structure in a blanket;
- Absence sharzhirovanija a job surface abrasive particles of wheels and polishing inks;
- Absence of thermal imperfections;
- Favorable microgeometry of the treated surface (at handling minimum parametres of a surface roughness are reached);
- Origin of favorable compressing residual voltages in a blanket;
- Smooth and stable heightening of microhardness of a surface [35, 82, 109, 127].
Use of methods IID with the account of assignment of an optimum condition of handling allows to improve operation properties of details, in particular to raise endurance, resistance of weariness and contact endurance [7, 91, 102, 106].
Among methods IID distinguish:
- Hardening in fraction;
- obkatyvanie rollers;
- Diamond vyglazhivanie;
- Ultrasonic hardening;
- Hardening by gyrating metal sweepers;
Etc. [43, 79, 90, 94, 102]
Methods of surface plastic deformation of details are widely illuminated in operations of such scientists, as Sulima A.M. [106], Saverin M. N [97], Suslov A.G. [108], Anisimova I.V. [4], Tumanov S.I. [114], Hvorostuhin A.A. [94], Ovseenko A.N. [75], Rykovskij B.P. [103], Papshev D.D. [83], Kudrjavtsev I.V. [95], Lebedev V. A [65, 66, 98], Priests of M. E [98], Babichev A.P. [123] and others isledovatelej.
Application of methods of surface plastic deformation of details leads to heightening of endurance and a limit of endurance of details on the average in 1,5...2 times, and contact durability on 30...40 % [31].
At a choice of a method of handling first of all it is necessary to consider operating performances of details which define parametres of quality of their blanket and design features.
For the reason that in the modern transport technics the overwhelming majority of details has a difficult profile of the external surface, the most suitable method of handling is hardening in fraction [39, 41]. Drobeuprochnitelnaja handling can be spent with the help drobemyotnyh the devices equipped centrifugal drobemyotnym with a sprocket which gives a fraction kinetic energy, and also pneumodynamic uprochnitelnyh devices of the pistol type which principle of operation consists in stream acceleration drobinok by means of the centralised system of compressed air [36]. All surfaces of details, or only sites of concentrators of voltages can expose to handling in fraction. Compactness of devices of local hardening allows use of methods at hardening of articles without them
Undocking and dismantle. Local hardening can sometimes appear considerably proizvoditelnee and is cheaper, than volume [123].
Process drobemyotnoj handlings is stated in Kudrjavtseva I.V.'s [95] operations, Saverina M. M [104], Papsheva D.D. [83, 84], Petrosova V.V. of [85] and other scientists.
But it is necessary to tell, that use of these methods of hardening at identical conditions of handling as the instrument of restoration of details at repair has no common sense. The basic deficiency of the given traditional circuit of hardening is the impossibility of timely change of a condition of handling for the purpose of shaping of necessary operation qualities. Besides it, application of the same conditions often leads to the phenomenon perenaklyopa at hardening process at which favorable residual voltages of compression are displaced deep into a detail blanket, and over them residual voltages of a stretching are organised, that, accordingly, leads premature razuprochneniju to a detail.
Now process of repair and restoration of details at the specialised enterprises integrates following methods:
• a working by stock removal
• abrasive handling (grinding, honingovanie, etc.)
• welding
• a building-up welding
• drawing of galvanic coverages
• repair by riveting
Restoration of operating performances of details by methods of surface plastic deformation practically is not offered, or is mentioned in the restricted aspect and reduced to use vyglazhivanija working surfaces of details. Such
In the image, the question of efficiency and expediency of repeated hardening of details in fraction during repair and restoration requires all-round consideration. In this connection research of efficiency of use of shock hardening in fraction at a stage restoration of details which have completed the assigned resource is offered.
The essence of an offered method consists in hardening of details in fraction by manufacture on the optimum conditions guaranteeing high level prochnostnyh of performances, and repeated handling at restoration for the purpose of deriving of properties necessary for the further maintenance and the parametres, allowing to raise probability of non-failure operation and an effective technical resource of articles. The common circuit of realisation of an offered method is presented on fig. 1.6.
Fig. 1.6. The circuit of realisation of process of hardening by manufacture and restorings of details after maintenance by means of handling in fraction: K - the control, KH - performances of quality of a blanket, EH - operating performances of details.
1.3.
More on topic methods of heightening of reliability of details from high-resistance steels:
- Zyk Evgenie Nikolaevich. HEIGHTENING of FATIGUE DURABILITY of DETAILS FROM HIGH-RESISTANCE STEELS BY MANUFACTURE And RESTORATION by SHOCK METHODS PPD. The thesis on competition of a scientific degree of a Cand.Tech.Sci. Moscow - 2018, 2018
- 1.3 Influence of ageing on operation properties of trumpet steels (prochnostnye properties, treshchinostojkost, resistance to fragile destruction, corrosion firmness, hydrogen ohrupchivanie)
- Drawing of foreign high technologies and management methods.
- the analysis of statistics of refusals of details of transport technics
- 2.1 Performance of examined steels
- TECHNOLOGICAL RECOMMENDATIONS ABOUT INCREASE IN FATIGUE DURABILITY AND THE TECHNICAL RESOURCE OF DETAILS AT HARDENING IN FRACTION
- the Analysis of innovative activity of high schools, an infrastructure condition kommertsializatsii high school researches and workings out
- 1.1 Models of ageing of trumpet steels
- Research of influence of deformation ageing on corrosion firmness of trumpet steels
- not destroying quality monitoring of details at PPD
- security of endurance of details at restoration