ENGINEERING GRAPHICS APPLIED TO THE ASSEMBLY PROCESS OF A SINGLE-CYLINDER HIGHPRESSURE STEAM ENGINE WITH CORLISS VALVE GEAR

This paper presents an engineering design-based investigation of a historical invention: a single-cylinder horizontal high-pressure steam engine with a Corliss valve gear designed by Arnold Throp. The research, grounded in engineering drawing, has enabled an understanding of the operation of this invention based on a 3D CAD model derived solely from original plans published in the Model Engineer magazine in 1982 and reproduced by Julius de Waal in 2018. Contributing to the field of industrial archeology, our novel research utilizes CAD, engineering drawing, and mechanical engineering principles to revitalize historical inventions. Our methodology allows for a detailed analysis of the design and function of these significant technological advancements, ensuring their legacy is preserved. However, challenges were encountered during the geometric modeling process due to missing dimensions for certain components and errors in others. To address these issues, dimensional, geometric, and kinematic constraints (degrees of freedom) had to be applied to ensure that the 3D CAD model was coherent and functional, and an interference analysis also had to be conducted. Ultimately, symmetry was discovered in the governor’s structure and the arrangement of the four valves within the cylinder block, particularly in the mechanism that operates the inlet valves. This symmetry is essential to ensure that forces and movements are distributed evenly during the steam exchange within the cylinder, allowing for more balanced work, reduced vibrations, and the optimization of 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.

Britons were world pioneers of the Steam Age. Thomas Savery built the first operational steam pump with no moving parts. Thomas Newcomen designed an atmospheric steam pump. James Watt was proposed by some commentators to be the "Father of the Industrial Revolution" because he designed super-efficient beam, rotary, and double acting steam engines for a host of emerging industries. Richard Trevithick built high pressure steam engines in both stationary and mobile formats, one of the latter becoming the first steam locomotive to operate on cast iron rails. His prototype was the progenitor of railway engines. Robert Stephenson designed and built the Rocket steam locomotive which became the template for steam locomotives across the world for the next century. By the late seventeenth century, a national shortage of wood had created a demand for coal as a substitute fuel. Whilst Britain possessed huge reserves of coal, some of its extraction required deep mining techniques. However, the curse of coal mines was their tendency to fill with water. Likewise, the flooding of copper and tin mines, particularly in Cornwall, was of great concern. Two Devonshire men—Savery and Newcomen—used their engineering skills to build static steam engines that could be used to pump out unwanted water from mines. The application of steam pumps in coal mines led to a colossal expansion of the coal industry, at relatively low cost, because the coal fines that were usually waste material could be used to generate steam. The invention of the steam engine was crucial to the industrialization of modern civilisation. Before them, we relied on power generated by wind, water, humans, and animals. Steam engines rank amongst the greatest inventions of all times. Their artificial source of power facilitated the exploitation of our mineral wealth. They relied on the burning of coal to produce heat to vaporise water into steam. The subsequent condensation of steam in a confined space created a vacuum which facilitated either a siphoning process or the movement of a piston. The steam engine was a complex invention that underwent a process of incremental development which, over the years, incorporated many important innovations. These resulted from an increased understanding of 'atmospheric pressure' and the nature of 'vacuum', as well as novel engineering improvements. Later, steam engines were used to hoist coal and mining machinery leading to an abundant supply of low-cost coal. At the time, long-distance freight was carried by road or canal. The fastest way to move people between urban centres was by horseback. Engineers and industrialist would use steam engines to power trains, steamboats and various machines present in manufacturing sites across the industrial world. The steam engine, in various formats was one of the most successful inventions of all times. As they got smaller, steam engines could be set up wherever mechanical power was needed. They powered Great Britain to prominence as the first industrialized nation in the World. Britain then emerged as the most powerful trading nation in the world. Over a period of 131 years, between 1698 and 1829, six British engineers and entrepreneurs were largely responsible for the development of the steam engines and steam locomotives that contributed so significantly to the first Industrial Revolution. These great British men were Thomas Savery, Thomas Newcomen, James Watt, Richard Trevithick, George, and Robert Stephenson. During this period of advancement, several excellent, British background scientists were working in related fields. These include Robert Hooke, Robert Boyle, Joseph Black (theory of latent heat {'hidden' heat and energy in steam}) and James Joule who determined the exact rate of exchange at which mechanical work is converted to heat. However, the inventions that these six engineers assembled appear to have been stimulated, not by the application of scientific knowledge and theories, but by their familiarity with on-site technical operations, their ingenuity, personal engineering skills, practical expertise, craftsmanship, repeated improvement trials, as well as a stroke of luck. Learning resulted from attempting new things.

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 investigation analyzes the design integrity from a mechanical engineering perspective of a single-cylinder high-pressure steam engine with a Corliss valve gear designed by Arnold Throp. This concerns a double-acting steam engine that incorporates a steam distribution system using a Corliss valve gear, whose blueprints were published in the Model Engineer magazine in 1982. This is a complex historical invention given the high number of components (120) that constitute it, and for which no information exists regarding its operating conditions. Once the 3D CAD model of the same was obtained, and given that no physical model exists to subject to testing, a linear static analysis was performed at two critical positions (top dead center and bottom dead center), determining the maximum gauge pressure at the steam inlet (working pressure), such that the minimum safety factor is within an optimal range with values between 2 and 4. Said linear static analysis was performed using the stress analysis module of Autodesk Inventor Professional 2024, applying the finite element method. The results obtained confirm that the optimal range of working pressures is between 4.1 and 7.8 MPa.

In this paper, the geometric modeling and virtual reconstruction of the double-acting steam engine designed by Agustín de Betancourt in 1789 are shown. For this, the software Autodesk Inventor Professional is used, which has allowed us to obtain its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Almost all parts of the steam engine are drawn on the sheets, but due to the absence of scale and space, it is insufficient to obtain an accurate and reliable 3D CAD (Computer-Aided Design) model. For this reason a graphic scale has been adopted so that the dimensions of the elements are coherent. Also, it has been necessary to make some dimensional and geometric hypotheses, as well as restrictions of movement (degrees of freedom). Geometric modeling has made it possible to know that the system is balanced with the geometric center of the rocker arm shaft, and presents an energetic symmetry whose axis is the support of the parallelogram where the shaft rests: calorific energy to the left and mechanical energy to the right, with the rocker arm acting as a transforming element from one to the other.

Motion analysis is increasingly applied to spine musculoskeletal models using kinematic constraints to estimate individual intervertebral joint movements, which cannot be directly measured from the skin surface markers. Traditionally, kinematic constraints have allowed a single spinal degree of freedom (DOF) in each direction, and there has been little examination of how different kinematic constraints affect evaluations of spine motion. Thus, the objective of this study was to evaluate the performance of different kinematic constraints for inverse kinematics analysis. We collected motion analysis marker data in seven healthy participants (4F, 3M, aged 27–67) during flexion–extension, lateral bending, and axial rotation tasks. Inverse kinematics analyses were performed on subject-specific models with 17 thoracolumbar joints allowing 51 rotational DOF (51DOF) and corresponding models including seven sets of kinematic constraints that limited spine motion from 3 to 9DOF. Outcomes included: (1) root mean square (RMS) error of spine markers (measured vs. model); (2) lag-one autocorrelation coefficients to assess smoothness of angular motions; (3) maximum range of motion (ROM) of intervertebral joints in three directions of motion (FE, LB, AR) to assess whether they are physiologically reasonable; and (4) segmental spine angles in static ROM trials. We found that RMS error of spine markers was higher with constraints than without (p < 0.0001) but did not notably improve kinematic constraints above 6DOF. Compared to segmental angles calculated directly from spine markers, models with kinematic constraints had moderate to good intraclass correlation coefficients (ICCs) for flexion–extension and lateral bending, though weak to moderate ICCs for axial rotation. Adding more DOF to kinematic constraints did not improve performance in matching segmental angles. Kinematic constraints with 4–6DOF produced similar levels of smoothness across all tasks and generally improved smoothness compared to 9DOF or unconstrained (51DOF) models. Our results also revealed that the maximum joint ROMs predicted using 4–6DOF constraints were largely within physiologically acceptable ranges throughout the spine and in all directions of motions. We conclude that a kinematic constraint with 5DOF can produce smooth spine motions with physiologically reasonable joint ROMs and relatively low marker error.

Geometric constraints and reasoning for geometrical CAD systems

Spatial coordination of a two-arm robot system subjected to kinematical and geometrical constraints

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 study proposes a method for automating the determination of assembly order by automating the derivation of the necessary connection relationships between the parts. The proposed method minimizes the information required for the initial conditions and automatically determines the feasible assembly orders. As a general rule, based on the assumption that the assembly order for a product is the reverse of the disassembly order, once the disassembly order is derived based on the 3D CAD model and the connection relationships between the parts, the assembly order can be determined. Until now, however, the relationships between the parts are decided manually by the attendant engineers, thus, hindering the full automation of the determination of the assembly order. To achieve full automation realistically, the connection relationships between the parts should be derived automatically from the 3D CAD model, for which this study proposes an efficient method. The components were extracted from the 3D CAD model, and the bolts were identified. The connection relationships between the parts were derived from the interference conditions determined while moving each part minutely. An association chart diagram was created from the obtained connection relationships, from which multiple assembly order candidates could be derived.

On the High Pressure Steam Engine

Third set of instructions in relation to the execution of the royal ordinances of the 29th of October, 1823, and 7th of May 1828, concerning high pressure steam engines

Circular of the 16th of July, 1828, to the Prefects of Departments, on the subject of the royal ordinances, of the 29th of October, 1823, and the 17th of May, 1828, concerning high pressure steam engines

High pressure steam engines and computer software (abstract)