Study of Optimal Cam Design of Dual-Axle Spring-Loaded Camming Device

The spring-loaded camming device (SLCD), also known as “friend”, is a simple mechanism used to ensure the safety of the climber through fall prevention. SLCD consists of two pairs of opposing cams rotating separately, with one (single-axle SLCD) or two (dual-axle SLCD) pins connecting the opposing cams, a stem, connected to the pins, providing the attachment of the climbing rope, springs, which simultaneously push cams to a fully expanded position, and an operating element controlling the cam position. The expansion of cams is thus adaptable to allow insertion or removal of the device into/from a rock crack. While the pins, stem, operating element, and springs can be considered optimal, the (especially internal) shape of the cam allows space for improvement, especially where the weight is concerned. This paper focuses on optimizing the internal shape of the dual-axle SLCD cam from the perspective of the weight/stiffness trade-off. For this purpose, two computational models are designed and multi-step topology optimization (TOP) are performed. From the computational models’ point of view, SLCD is considered symmetric and only one cam is optimized and smoothened using parametric curves. Finally, the load-bearing capacity of the new cam design is analyzed. This work is based on practical industry requirements, and the obtained results will be reflected in a new commercial design of SLCD.

The Investigation of Interlaminar Failures Caused by Production Parameters in Case of Additive Manufactured Polymers

The use of three-dimensional (3D) printing technologies is an ever-growing solution. The product realized in many cases is applicable not only for visual aid, or model, but for tool, or operating element, or as an implant for medical use. For correct calculation, a proper model that is based on the theory of elasticity is necessary. The basis of this kind of model is the knowledge of the exact material properties. The PLA filament has been used to perform this study for matrix material. Our presumption is that the different layers do not fuse completely, and they do not fill up the space available. The failures between the layers and the deposited filaments and the layer arrangement could be the reason for the direction-dependent material properties of the 3D printed objects. Based on our investigation, we can conclude that the increase of the layer thickness and printing speed adversely affect the mechanical properties of the product.

Prevention of Oil Spills During Excavation Work Using Electromagnetic Sensors

This paper presents an analysis of solution to the problems associated with mechanical damage to pipelines. A method of preventing accidental oil spills during excavation using electromagnetic sensors is proposed. The advantages of this method versus alternative options are described herein. A review of existing sensors and methods of their installation on the operating element of excavation equipment is presented. The optimal design solution ensuring accident-free excavation is developed. The economic effect of introducing this technology in the production processes of the oil and gas sector companies is shown.

Investigation of sectional operating elements for conveying agricultural materials

The paper covers the results of the theoretical and experimental investigation of the developed sectional operating element of a flexible screw conveyer designed for transporting bulk agricultural materials. In order to determine the correlation between the design parameters of the hinged screw sections and the minimum permissible radius of curvature of a processing line, the analytical dependences have been deduced. The results of the experimental studies aimed at determining the efficiency of a screw conveyer and the level of the grain material damage depending on the change in design, kinematic and technological parameters of an operating element are presented.

PARTICLE MOTION OVER THE EDGE OF AN INCLINED PLANE THAT PERFORMS AXIAL MOVEMENT IN A VERTICAL LIMITING CYLINDER

Differential equations of a relative material particle motion over the edge of an inclined flat ellipse that rotates around the axis of a vertical limiting cylinder have been deduced. The position of a plane relative to the axis of the rotation is set by the angle ranging from zero to ninety degrees in its value. If the angle is equal to zero, the plane is perpendicular to the axis of rotation and if the angle is equal to ninety degrees, it passes through the axis of rotation. The equations have been solved using numerical methods. Analytical solution has been found for certain angles. The aim of the research is to investigate the transportability of a technological material in a vertical direction by a cascade operating element that rotates in a cylindrical cover. The working part of the operating element is an inclined rigid plane, which is limited by an ellipse — the line of its contact with a cover. The objective of the research is to analytically describe the movement of a single particle of the technological material on two surfaces, namely, an inclined plane and a vertical cover. The research methodology is based on the methods of differential geometry and the theory of surfaces, theoretical mechanics and numerical methods of solving differential equations. The paper presents a first developed analytical description of the relative particle motion in an ellipse — a contact line of an inclined plane and a limiting vertical cylinder, in which the inclined plane rotates. The kinematic characteristics of such motion have been determined.

Determination of the Energy Capacity of Face Rock Breaking by the Geokhod’s Knife Operating Element and its Dependence on the External Propeller’s Pitch

The article contains a method for determination of the energy capacity of face rock breaking by the knife operating element of the geokhod. In addition, the dependence of the breaking energy capacity on the pitch of the geokhod’s external propeller was revealed. The relevance of the study was considered. In order to set goals and objectives of the study, work features of new-class mining machines – geokhods and fundamental principles of geokhod technology were presented. Advantages and disadvantages of existing methods for determination of the energy capacity of rock breaking were identified, and the possibility of using them in calculation of power parameters of the geokhod’s knife operating element was assessed. Power and geometrical parameters of the geokhod’s knife operating element were determined, which affect the energy capacity of rock breaking. To determine the influence of the external propeller’s pitch on the breaking energy capacity, geometrical parameters of the knife operating element and parameters of mining conditions of workings were substantiated. As a result of the study, it was revealed that the energy capacity of rock breaking by the knife operating element decreases non-uniformly as the pitch of the external propeller increases.

Development of the Viable System Model of Partner Relationship Management of the Company

This paper considers the main instruments for relationship management between the company and different partners. The purpose of the study is to improve the theoretical foundations of the development of a system of total relationship management of the company with the main groups of interaction actors, taking into account relationships with all groups of partners of the company. The model of the relationship management system of the company on the basis of methodical apparatus of cybernetic modeling of viable systems is proposed. The model of the relationship management system of the company is presented as an entity (a metasystem) and an object of management (operating element), which is proposed in the form of relationship management processes with main groups of partners. The system of inter-company interactions, which reflects the development of individual relationship with a certain partner, is presented. Based on the structural-level and metasystem approaches, key levels and structure of enterprise relationships are identified. Five levels of relationship between the company and its partners – element, component, subsystem, system-wide, and metasystem levels are identified. These levels are presented in the form of recursive structure of the viable model of relationship management system of the enterprise.

Determination of Building Mortar Mixers Effectiveness

The peculiarities of building mortar mixes preparation in cyclic compulsory mixers of various designs have been considered in this article. The work of mixers with a horizontal shaft, a vertical shaft, beaters, screw straps, as well as planetary motion of mixing stars with beaters have been described in detail. The main attention here is paid to the constructive performance of machinery. A relative assessment is given to the manual bearing groups. The multi-purpose system of numerical indices necessary for the performance assessment of mixers’ running efficiency is proposed and defined in this paper. The design of the mixers is considered in this research according to the number of components of the mixture particles motion, which arise from the constrained influence of the movable operating element. The indicators of net weight and area in the plan are attributed to the productivity. The general method of determining the coefficient for assessing the impact, exerted by the design of the mixers on their running efficiency, has also been developed by the authors of this scientific investigation. The obtained data will enable to investigate and improve the design of the mixers, finding the ways to increase their working efficiency.