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In this research, we present the results of analyzing the technical feasibility of an old invention by Henry Muncaster from the perspective of mechanical engineering, specifically focusing on the resistance of materials. The invention is a two-cylinder steam engine with a parallel motion crosshead, for which plans were published in the Model Engineer magazine in 1957. This complex device, composed of 76 elements and lacking descriptive information, has been the subject of a recent article that illustrated its design through the engineering drawing discipline and a 3D CAD model. To provide reliable information and conduct a comprehensive study of its technical feasibility, an extensive linear static analysis was performed. This analysis considered two critical positions of the piston inside the cylinder: upper dead center and lower dead center. We determined the optimal range of working pressures necessary to achieve a safety factor within the optimal design range of two to four. The results include von Mises stresses, displacements, and safety factor distributions, confirming that the optimal working pressure range for steam intake is between 1.885 and 3.550 MPa. This ensures that the safety factor values remain between 2.01 and 3.78.

This article analyzes the mechanical behavior of a single-cylinder horizontal steam engine with a crosshead trunk guide designed by Henry Muncaster. This double-acting steam engine was incorporated as an engine in various means of locomotion, and its drawings were published in Model Engineer magazine in 1957. This historical invention, for which there is no detailed information about its operation, presents great complexity because of the large number of components (44) of which it consists, transforming the reciprocating movement into rotary movement. The research carried out consisted of carrying out a linear static analysis in two critical positions (lower dead center and upper dead center) and determining the optimal range of working pressures in order to achieve a safety factor located in the optimal design range with values between 2 and 4. This linear static analysis was carried out using the Stress Analysis module of the Autodesk Inventor Professional 2024 software, applying the finite-element method (FEM). The results obtained regarding the von Mises stresses, displacements, and safety factors confirm that the optimal range of working pressures (maximum admissible steam pressure during admission) is between the values of 0.165 and 0.320 MPa.

This paper explores a historical innovation created by Henry Muncaster: a stationary steam engine featuring a single-cylinder horizontal design with a crosshead trunk guide. Through the application of engineering graphics techniques, we have elucidated the functioning of this invention by developing a 3D CAD model based on the original drawings published in Model Engineer magazine in 1957. However, the geometric modeling process faced challenges due to missing and erroneous dimensions for several components. Consequently, dimensional, geometric, and movement constraints were applied to ensure the coherence and functionality of the 3D CAD model, alongside conducting an interference analysis. Ultimately, the proper alignment of the cylinder and crosshead was ascertained, which is crucial for maintaining uniform forces and motions within the steam engine. This alignment is pivotal for achieving balanced operation, minimizing vibrations, and enhancing the overall efficiency of the invention.

This article presents an investigation into a historical invention consisting of a stationary steam engine designed by Henry Muncaster: a two-cylinder entablature steam engine with parallel motion crosshead. The present interdisciplinary research, based on the theoretical and methodological concepts of engineering drawing and computer-aided design, has allowed us to understand the operation of this invention from the 3D CAD model of the invention obtained thanks to the original drawings published in the magazine Model Engineer in 1957 and reproduced in 2017, since there is no descriptive information related to the invention. However, there have been drawbacks in the geometric modeling process since the dimensions of some components did not exist and in other cases they were erroneous. For this reason, dimensional, geometric and movement constraints (degrees of freedom) had to be applied so that said 3D CAD model would be coherent and functional, and an interference analysis also had to be performed. Finally, the existing symmetry in the arrangement of the cylinders and the crosshead has been discovered, it being essential to guarantee that the forces and movements are uniform on both sides of the steam engine, and allowing the work to be carried out in a more balanced manner by reducing vibrations and improving the overall efficiency of the invention.