GB2397260A

GB2397260A - Forming metal pipe and sheet

Info

Publication number: GB2397260A
Application number: GB0323941A
Authority: GB
Inventors: Morry Hollensen
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-01-10
Filing date: 2003-10-13
Publication date: 2004-07-21
Anticipated expiration: 2023-10-13
Also published as: AU2003200073A1; GB0323941D0; GB2397260B

Abstract

A method of forming a radius on an edge of a metal plate, the edge having a certain profile, the method comprising the steps of forming metal pipe to substantially conform to the profile of the edge of the metal plate, removing a section of the metal pipe in a longitudinal direction (cut along line A-A) so to expose an edge having a profile complementary to the profile of edge of the metal plate, and joining the metal pipe and the metal plate along the said edges. Also disclosed is subsequently removing another section of pipe (cut along line C-C), then joining a second section (Fig 8 or 9,5) of metal plate to the second edge of the metal pipe (see figure 10). The product is a hood suitable for use as a traction engine end cover.

Description

A METHOD OF FORMING METAL

FIELD OF THE INVENTION

This invention is concerned with metal forming and, in particular, is concerned with a method of forming a radius on an edge of a section of metal plate. The invention finds particularly advantageous application in the manufacture of limited numbers of parts in which metal plate sections are to be oriented at right angles to each other and in which it is desired to form a smooth radius between the plate sections.

BACKGROUND

The present invention is likely to be of particular interest to those who restore antique equipment such as traction engines, or who construct scale models of such equipment. Those who restore such equipment are often faced with the problem of having to replace pasts that have become too badly damaged or corroded to be serviceable, or that are simply missing. In the case of both full size equipment, and scale models, many parts are not commercially available, and must be individually manufactured. In the case oi parts such as traction engine end covers, for example, it is often desirable to produce a smooth radius between the front and side portions of the covers.

There are known manufacturing techniques for shaping metal parts so as to produce a smooth radius on the edge of metal plates having curved or otherwise irregular profiles.

Typically, hydraulic metal presses are used to produce large numbers of identical metal parts.

However, it is not cost effective to produce expensive dies and formers for such presses, when only a small number of parts are required. A common approach where a single part, or a small number of parts, is required, is to heat the metal plate to a temperature sufficient to make it malleable, and to shape the metal plate using traditional blacksmithing tools such as anvils, mallets and hammers. The principal disadvantage with this approach is that it relies on the individual skill of the blacksmith and may not produce parts of consistently high quality and accuracy.

Unfortunately, few people with an interest in restoring antique equipment such as traction engines, or in constructing scale models of such equipment, are fortunate enough to have access to the types of manufacturing facilities, such as hydraulic presses, that needed for the manufacture of some of the parts required for such equipment or models. Similarly, few people have access to heating furnaces and fabricating formers and other blacksmithing tools needed to make pasts on a one-off basis. Even if they do have such access to these things, they rarely have the requisite skill to shape such parts with the high degree of accuracy required for a truly professional finish.

The present invention provides a simple method whereby small numbers of parts may be produced with a high degree of accuracy. A professional finish may be achieved by anyone without advanced metalworking expertise, and without the need for expensive equipment.

SU1\IMARY OF THE INVENTION In accoT-clance with the present invention there is provided a method of forming a radius on an edge ova metal plate, the edge having a certain profile, the method comprising the steps of forming metal pipe to substantially conform to the profile of the edge of the metal plate removing a section of the metal pipe in a longitudinal direction so to expose an edge having a profile complementary to the profile of edge of the metal plate joining the metal pipe and the meta] plate along the said edges.

Preferably, the metal pipe has a wal] thickness substantially the same as the thickness of the metal plate.

Advantageously, a i'urther section of the metal pipe of the metal pipe is removed in a longitudinal direction so as to leave an arcuate section of the metal pipe extending through approximately 90 degrees, and a second section of metal plate is joined to the metal pipe along the edge exposed by the removal of the further section of metal pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the present invention is hereinafter described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a front view of a section of metal plate having a shape generally representing the shape of the end section of a traction engine; Figure 2 is a side view of the section of metal plate illustrated in Figure 1; Figure 3 is a side view of a section of metal pipe that has been shaped to conform substantially to the shape of the section of metal plate illustrated in Figure 1; Figure 4 is an end view of the section of metal pipe illustrated in Figure 3; Figure 5 is a side view of the metal plate and the metal pipe after a section of the metal pipe has been removed, and the metal plate and the metal pipe have been welded together; Figure 6 is an end view of the joined metal plate and metal pipe illustrated in Figure 5; Figure 7 is the same view as illustrated ITI Figure 6, but after a further section of the metal pipe has been removed; Figure 8 is a side view of a second section of metal plate; Figure 9 is an end view of the section of metal plate illustrated in Figure 8; Figure 10 is the same view as illustrated in Figures 6 and 7, but after the second section of metal plate has been welded to the metal pipe; Figure 1 l is a front view of a section of metal plate having a shape generally representing the shape of the end section of a traction engine, which end section also has a fire door; Figure l 2 is a side view of the section of metal plate illustrated in Figure 11.

DETAILED DESCRIPTION OF THE PREFERRED EMRQDIMENT

Referring now to the accompanying drawings, Figure 1 illustrates a metal plate 1 having an edge 2 on which a radius is to be formed. Figure 2 illustrates the same section of metal plate, having a thickness t, from a side view. Figures 1 and 2 are generally illustrative of the bell-ended cover of an antique traction engine. The plate is shown with a relatively simple shape, but the invention is equally applicable to more complex workpieces, such as in the case where the cover also has a fire door, such as illustrated in Figures 11 and 12.

In order to create the desired radius on the edge of the plate 1, a length of metal pipe 3, as shown in Figure 3 is first selected. The thickness t of the metal pipe 3 is selected to be substantially the same as that of the metal plate l, and its diameter is selected to provide the desired radius. Referring to Figure 3, the length of metal pipe 3 is bent, using any S conventional pipe-bending method, so that its shape substantially conforms to the profile of the edge 2 of the metal plate 1. The metal pipe is then cut longitudinally along centre line A-A using a suitable cutting method, such as flame cubing. A further longitudinal cut is then made along line B-B so that a section of pine comprising approximately 9() dcgrces of the circumference of the pipe 3 is removed. If the cuts have beer. made using flame-cuttir,g equipment, then it will he necessary to smooth off the edges with a suitable tool, such as a grinder or metal file.

The exposed edge of the metal pipe 3 alone centre line A-A is then aligned with the edge 2 of the metal plate 1, whose profile it complements. The parts may then be welded together in conventional fashion to form a workpiece 4 as illustrated in Figures 5 and 6.

A fulfiller longitudinal cut is then made along line C-C, so that a further section of the metal pipe 3 is removed from the workpiece 4, leaving a section comprising approximately degrees of the circumference of the metal pipe 3. Again the cut may be made by flame cutting. Figure 7 illustrates the workpiece 4 after the further section of metal pipe 3 has been removed.

A second section of metal plate 5, as illustrated in Figures 8 and 9 is then bent and shaped so that one edge aligns with the now exposed edge CC. The section of metal plate 7 is then welded to the workpiece 4 along edge C-C, again in conventional fashion. Figure 10 illustrates the workpiece 4 after the further section of metal plate 7 has been attached.

It will be appreciated that it would be possible to cut the metal pipe along lines A-A and C-C only, thereby removing in a single operation a section of the pipe comprising 270 degrees. However, it is considered to be advantageous if the sections of pipe are removed in two stages, as described above. This is because, if a smaller section of pipe is removed initially, the pipe better retains its shape during the welding process. Retaining a larger section of pipe also makes it easier to handle during the welding process.

Figures 11 and 12 illustrate a similar end cover 8 which also incorporates a fire door 9. In this case, by simply perforating the method of the present invention twice, smooth radii rl and r2 may be created, thereby producing a finished article of high quality and professional appearance. From this, it can be seen that the invention is applicable to the production of considerably more complex parts.

Many modifications will be apparent to those skilled in the aft without departing from the scope of the present invention as herein described with reference to the accompanying drawings. For example, whilst the invention is described with reference to the use of a single length of metal pipe bent to the appropriate shape, it would be possible in many applications to use a number of commercially available pipe fittings, joined together to form the desired shape.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

CLAIMS: 1. A method of forming a radius on an edge of a metal plate, the

said edge having a certain profile, the method comprising the steps of: forming metal pipe to substant.ial]y conform to the profile of the said edge of the metal plate; removing a section of the metal pipe in a longitudinal direction so to expose an edge having a profile complementary to the profile of the edge of the metal plate; and joining the metal pipe and the metal plate along the said edges.
2. A method as claimed in claim], wherein the thickness of the metal pipe is substantially the same as the thickness of the metal plate.
3. A method as claimed in claim 1 or claim 2, including the further steps of: removing a funkier section of the metal pipe in a longitudinal direction so as to leave an arcuate section of the metal pipe extending through approximately 90 degrees; and joining a second section of metal plate to the metal pipe along the edge exposed by the removal of the further section of metal pipe.
4. A method of joining a first section of metal plate substantially at right angles to a second section of metal plate, comprising the steps of: forming metal pipe to substantially conform to the profile of an edge of the first metal plate; removing a section of the metal pipe in a longitudinal direction so to expose an edge having a profile complementary to the profile of the edge of the first metal plate; joining the metal pipe and the first metal plate along the aforementioned edges; removing a further section of the metal pipe in a longitudinal direction so as to leave an arcuate section of the metal pipe extending through approximately 90 degrees, and exposing a second edge of the metal pipe; and joining the second section of metal plate to the second edge of the metal pipe.