Analysis of a Replaceable Cutting Tooth of Bucket Chain Excavator

This paper briefly outlines the design of replaceable cutting teeth of bucket chain excavator, which are attached to a holder with a detachable joint. The description of the rock cutting process is very complex, so the investigation of the effect of lateral forces is complicated through cutting tests. We use accordingly numerical analysis to examine some segments of the cutting process. Our main objective is to present the finite element analysis of cutting teeth in which the linear increase of the lateral force is taken into consideration. The finite element analysis is a powerful technique, which is enabled to compute the stress and displacement distribution in cutting teeth. The simulation results have shown that the maximum stresses decrease if the lateral force increases. The geometry of the optimized cutting teeth will be safe under the given loading conditions.

Experimental and Numerical Study of Pressure Intensity in Detachable Joints of D Series Pumps

The object of study is a single-stage double-suction axially split volute casing centrifugal pump. Background. In the design process of pumps, the problems associated with ensuring the tightness of the axial joint of a pump casing being under the effect of mechanical and temperature loads, are being solved. During the study of axial joint tightness, numerical calculation methods are used to estimate the pressure intensity on the contacting surfaces. A detachable joint under the external load satisfies the criterions of the tightness if the pressure intensity on the sealing surfaces is higher than values of the specific pressure prescribed by regulations. However, inability to experimentally determine the pressure intensity on the contacting surfaces has so far prevented to assess the accuracy of results obtained by the numerical calculation methods. Objective. In order to verify the numerical results obtained by mathematical models, an experiment was carried out using a special Prescale film that registers the magnitude of the contact pressure on the joint of the specimen model of the flange fragment. Based on the experimental results, an analysis of the pressure intensity distribution was conducted. Methods. To conduct the experiment, there was developed a method for determining the pressure intensity on the contacting surfaces according to the proposed scheme of the specimen of the flange fragment. Results. A comparative analysis of the solving results obtained for the contact problem on the finite-element models of the flange fragment and the zone of the pump casing joint in the discharge chamber area showed a good coincidence of the results. Analysis of results obtained experimentally on the specimen of flange fragment and results of the numerical calculation on the flange fragment model also showed a good agreement. Conclusions. Therefore, results of the calculation of the pressure intensity in the detachable joints on mathematical models have been experimentally confirmed.

Detachable Joint Sealing Based on Leakage Duct Hydraulic Resistance

The types of detachable fixed joints with elastic and plastic sealing are considered, their disadvantages are indicated. A new design of the sealing unit for fixed and movable joints is presented, eliminating these disadvantages. The tightness of the structure is ensured by increasing the hydraulic resistance of the leakage channel of the sealed medium, which has a cross-section in the form of an equilateral triangle. The channel is spirally placed in the contact zone of the sealing surfaces, the inlet and outlet of which are located along the inner and outer diameters of the mating surfaces, respectively. Expressions for calculation of the proposed type of joints for real conditions of its use are presented.

Parameters of Construction for Applications of Metal Foams

ABSTRACTThis article will present characteristics that have great importance for the industrial use of metal foam structures. In detail, these areDesign criteria for detachable joint connectionsInvestigation of the thermal behavior of sandwich composites