Increasing the Durability of Critical Parts in Heavy-Duty Industrial Machines by Deep Cryogenic Treatment

Krot, Pavlo; Bobyr, Serhii; Zharkov, Ivan; Prykhodko, Ihor; Borkowski, Przemysław

doi:10.1007/978-3-030-97822-8_14

Cited by 2 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, steel grade for bolts in the upper deck joints should be thoroughly selected to have simultaneously high yield stress, hence, higher endurance limit, and high impact toughness. Such contradictory properties can provide special heat treatment routes for alloy steels including the deep cryogenic treatment stage, which also eliminates internal stresses after heat treatment [87,88].…”

Section: Discussionmentioning

confidence: 99%

Diagnostics of Bolted Joints in Vibrating Screens Based on a Multi-Body Dynamical Model

Krot,

Shiri,

Dąbek

et al. 2023

Materials

View full text Add to dashboard Cite

The condition-based maintenance of vibrating screens requires new methods of their elements’ diagnostics due to severe disturbances in measured signals from vibrators and falling pieces of material. The bolted joints of the sieving deck, when failed, require a lot of time and workforce for repair. In this research, the authors proposed the model-based diagnostic method based on modal analysis of the 2-DOF system, which accounts for the interaction of the screen body and the upper deck under conditions of bolted joint degradation. It is shown that the second natural mode with an out-of-phase motion of the upper deck against the main screen housing may coincide with the excitation frequency or its higher harmonics, which appear when vibrators’ bearings are in bad condition. This interaction speeds up bolt loosening and joint opening by the dynamical loading of higher amplitude. The proposed approach can be used to detune the system from resonance and anti-resonance to reduce maintenance costs and energy consumption. To prevent abrupt failures, such parameters as second natural mode frequency, damping factor, and phase space plot (PSP) distortion measures are proposed as bolt health indicators, and these are verified on the laboratory vibrating screen. Also, the robustness is tested by the impulsive non-Gaussian noise addition to the measurement data. A special diagram was proposed for the bolted joints’ strength capacity assessment and maintenance actions planning (tightening, replacement), depending on clearance in the joints.

show abstract

Section: Discussionmentioning

confidence: 99%

Diagnostics of Bolted Joints in Vibrating Screens Based on a Multi-Body Dynamical Model

Krot,

Shiri,

Dąbek

et al. 2023

Materials

View full text Add to dashboard Cite

show abstract

“…It is well known that deep cryogenic treatment (DCT) can significantly increase the properties of alloy steels [8][9][10][11]; thus, it is used as a final treatment for many technologies and industries, such as materials science [12,13], tool and steel industries [14][15][16][17][18], manufacturing of rolls [19], and automotive industry [20]. This process uses sub-zero temperature, below −125 • C, which is created by liquid nitrogen [18], as the preferred cooling medium.…”

Section: Introductionmentioning

confidence: 99%

Increasing the Wear Resistance of Structural Alloy Steel 38CrNi3MoV Subjected to Isothermal Hardening and Deep Cryogenic Treatment

Bobyr,

Krot,

Parusov

et al. 2023

Applied Sciences

Self Cite

View full text Add to dashboard Cite

In the production of critical parts for various machines and mechanisms, expensive structural steels are used alloyed with chromium, nickel, molybdenum, and vanadium. In practice, the wear resistance of parts, especially under severe operating conditions, may be insufficient due to uneven microstructure and the content of retained austenite. Therefore, increasing the operational stability of various products made of alloy steels is an important task. The purpose of this work is to investigate the effect of isothermal hardening from the intermediate (γ+α)-area and the duration of deep cryogenic treatment on the structure formation and frictional wear resistance of 38CrNi3MoV steel. The isothermal hardening promotes the formation of the required multiphase microstructure of 38CrNi3MoV steel. The influence of the duration of deep cryogenic treatment on the microhardness, amount of retained austenite, fine structure parameters, and friction wear of 38CrNi3MoV steel are established. Complex heat treatment of 38CrNi3MoV steel, according to the proposed mode, makes it possible to achieve a significant decomposition of retained austenite to martensite, which leads to an increase in frictional wear resistance of ~58%.

show abstract

Increasing the Durability of Critical Parts in Heavy-Duty Industrial Machines by Deep Cryogenic Treatment

Cited by 2 publications

References 14 publications

Diagnostics of Bolted Joints in Vibrating Screens Based on a Multi-Body Dynamical Model

Diagnostics of Bolted Joints in Vibrating Screens Based on a Multi-Body Dynamical Model

Increasing the Wear Resistance of Structural Alloy Steel 38CrNi3MoV Subjected to Isothermal Hardening and Deep Cryogenic Treatment

Contact Info

Product

Resources

About