The Basics of Developing an Alternative Concept for Commercial and Military Vehicle Operation (Random Strategy)

The efficiency of commercial automobiles and wheeled military vehicles mainly depends on the choice of maintenance (M) and current repair (CR) concept. In the paper the difficulties of adapting the (M) and (CR) planning strategies to the structural characteristics of modern transport facilities are pointed out. The advantages of using the (M) and (CR) random strategy for transport facilities based on the stochastic nature of failures and malfunctions are substantiated. Considering the failures and malfunctions as random values and identifying the patterns of their distribution based on γ percentage resources, it is proposed to develop a list of regulated maintenance and repair work, periodicity and labor intensity based on a random strategy, which will increase the efficiency of preserving the technical resource of the rolling stock throughout the entire life cycle of the vehicle.

SCIENTIFIC APPROACH TO THE METHODS OF INCREASING THE LIFE CYCLE OF WHEELS OF RAILWAY VEHICLES

The value of the life cycle of rolling stock wheels is determined by the frequency of maintenance, in the process of which the turning is carried out to restore the profiles of the rolling surfaces, or the replacement of completely worn wheels. Traffic safety depends on the technical condition of the wheels of locomotives and wagons. Maintenance and repair of wheelsets accounts for about 30% of all costs of Ukrzaliznytsia's rolling stock repair units. Wheel repair technologies are based on the complete restoration of wheel profiles by turning, using which, their life cycle is reduced, and costs increase by 20% or more. The railways of Ukraine use an outdated, unreasonable, inefficient system of control over the formation of rolling surfaces in operation. Therefore, there is a need to create a scientifically sound approach to methods of extending the life cycle of the wheels of locomotives and wagons while ensuring the safety of railway rolling stock. According to the proposed scientific approach, the wheel profile is restored to optimal parameters, which provides an extended life cycle of wheelsets. As a result of the developed scientific approach the life cycle of wheel pairs will increase by 15… 25% and the expenses of the railway for their repair will considerably decrease.

THE IMPROVEMENT MECHANICAL BRAKE SYSTEM OF THE PASSENGER СAR

A set of theoretical scientific researches is carried out in the work, which proves that with the use of different types of brake pads in passenger cars some elements of the typical design of the mechanical brake system need to be modernized. Analytical calculations of the brake lever transmission of passenger cars are performed on the basis of the 2D scheme-model. Due to this, ways to improve the most important elements of lever transmission in passenger cars under the conditions of composite pads are proposed. The analysis of the forces acting in the typical design of the lever transmission of a passenger car for different types of pads is performed. The strength of important elements of the mechanical brake system is calculated by applying the finite element method. It is proposed to use the capabilities of the software package Femap Siemens PLM Software, which allows you to optimize the elements of the mechanical system of passenger cars. An example of topological optimization of some elements of brake lever transmission of a passenger car is given. By improving the elements of the mechanical brake system for the use of composite pads in passenger cars, greatly simplifies their design, facilitates maintenance and repair, also reduces the weight of the system as a whole and cost and significantly increases the level of traffic safety.

Maintenance and repair of marine diesel engines. In 4 volumes

The second volume of the textbook shows the design features of the main components and parts of the movement groups that affect their working conditions and methods of maintenance and repair. Recommendations on the frequency of regulated work and possible malfunctions are given. With examples from ship practice, the methods of disassembly-assembly, defection and repair of the main components and parts of the movement groups are considered. The previous and subsequent volumes show the design features, provide recommendations on the frequency of regulated work and maintenance and repair of other components and parts of marine diesel engines. It is intended for students of higher educational institutions in the specialty "Operation of marine power plants" and university teachers. It may be useful for ship mechanics.

Maintenance and repair of marine diesel engines

The first volume of the textbook shows the features of the layout of marine diesel engines, the composition of the external inspection and control of their work, the designs of components and parts of the frames that affect their working conditions and methods of maintenance and repair. Recommendations on the frequency of regulated work and possible malfunctions are given. With examples from ship practice, the methods of disassembly-assembly, defection and repair of the main components and parts of the framework are considered. The following volumes show the design features, provide recommendations on the frequency of regulated work and maintenance and repair of other components and parts of marine diesel engines. It is intended for students of higher educational institutions in the specialty "Operation of marine power plants" and university teachers. It may be useful for ship mechanics.

Voyages of maintenance: Exploration, infrastructure, and modernity on the Krusenstern–Lisianskii circumnavigation between Russia and Japan from 1803 to 1806

Against the common association of voyages of exploration with discovery and the arrival of modernity, this essay argues that maintenance and repair were essential to the success of such voyages and that maintenance and innovation are best seen as fundamentally integrated. Using the Russian circumnavigatory voyage of Adam von Krusenstern and Urey Lisianskii in 1803–7 as a case study, the essay explores the diverse forms and roles of infrastructure and repair work in enabling a voyage of exploration, and reveals the tensions and debates that considerations of maintenance evoked among ships’ officers, crews, and the peoples they encountered.

A Case Study - Life Extension of Offshore Bridge Bearings

Structural bearings of 47 offshore platform-link bridges with average age of 40 years were inspected and recommended for replacements due to their poor condition. Replacement of bridge bearings involves major risk and production interruptions given the structural modifications, and critical piping and E&I disconnections required for safe jacking-lifting activities required during the process. This paper presents the approach adopted to assure the integrity of the bridges and extend their lives without the need to replace the bearings. The approach employed failure mode and effect analysis to identifying and narrowing down areas that need focused efforts while tackling the problem. Scenario based structural assessments were carried out to examine the impact of the level of movement-allowing bearings functionality on the integrity of the bridge and its supporting structures; identify critical locations to be targeted during focused inspections; and establish envelopes for monitoring thermal expansion and contraction of the bridges. Guidelines were developed and implemented for integrated inspection-maintenance and repair campaign, which aimed to tackle corrosion issues and to install movement-monitoring indicators. Indicator seasonal monitoring is employed to establish the functionality of bearings on the long-term. The what-if structural assessments revealed that even in the worst-case scenario (in which the bearing are completely jammed) the option of local strengthening of the bridge and its supporting elements is more attractive than bearing replacement. The integrated inspection-maintenance and repair campaigns revealed that excessive corrosion levels observed from historic visual inspections on external non-critical bearing components (e.g: guide plates, angles, etc.) is not indicative of the condition of the internal load-bearing components (pedestals) which experienced much lower corrosion levels. The seasonal monitoring of bridge movements revealed that the 40+ years old Teflon pads are still functional and allow the bridges expansion and contraction. The developed holistic approach enabled demonstration of the fitness for service of the bearings, and provided means for assuring their long-term performance through monitoring. The results assured safety, integrity and delivered significant cost savings through aversion brownfield modifications, and production loss associated with bridge jacking and bearing replacement operations.