GB1588376A

GB1588376A - Gas rails

Info

Publication number: GB1588376A
Application number: GB818478A
Authority: GB
Original assignee: TUBE MANIPULATIONS Ltd
Current assignee: TUBE MANIPULATIONS Ltd
Priority date: 1978-05-22
Filing date: 1978-05-22
Publication date: 1981-04-23

Description

(54) IMPROVEMENTS RELATING TO GAS RAILS (71) We, TUBE MANIPULATIONS LIMITED, of Halesowen Industrial Park, Halesowen, West Midlands B62 8BG, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to gas rails, which are used primarily on domestic gas cookers to form a manifold connecting the gas supply to a plurality of individual burners via separate control taps.

The prior art consists firstly of iron castings made in sand moulds, which are heavy, require machining to provide flat faces for the gas to seat upon, and require sealing against imperfections and blow holes in the casting and against the possibility of particles of the sand remaining in the casting and subsequently entering the taps and jamming the same.

The prior art also comprises aluminium alloy die castings, which require particularly expensive dies which are not economically feasible for short runs of production, and also require at least some machining.

Thirdly, the prior art comprises aluminium alloy extrusions which also need expensive tools for their production, and all of these first three forms of prior art involve substantial thicknesses of metal.

Fourthly, the prior art comprises sheet metal manifolds with welded seams, which avoid many of the problems of the first three forms of the prior art, but which are themselves subject to certain disadvantages.

In accordance with one aspect of the present invention we provide a gas rail made from a lightweight steel tube which has been formed from its initial shape to a crosssection provided with at least one flat face, said one flat face being formed with one or more holes in registry with the interior of the tube and having one or more control taps mounted thereon to control supply of gas from a respective hole.

In accordance with another aspect of the present invention we provide a method of making a gas rail wherein a length of lightweight steel tube is subjected to a forming operation to produce a tube cross-section provided with at least one flat face, said one flat face is formed with one or more holes in registry with the interior of the tube, and one or more gas taps are attached to said one flat face so as to control gas supply from a respective hole.

The tube may initially be of round section and may be a seamless tube or tube with a welded seam.

It is found that an assembled and complete rail using the steel tube is substantially cheaper than the prior art after assembling and avoids all of the problems.

The forming operation may be profile rolling or pressing.

In one preferred form of the invention the tube is profile rolled or pressed to what may be called a "hat" section, that Is to say, to have a flat face and a generally square shaped or arcuate wall extending to and from the flat face but having a transverse dimension which is less than that of the flat face, so that a pair of flanges project coaxially from opposite sides of the square or other shape.Each of the flanges will comprise a double thickness of metal from the original tube wall, and this provides convenient mounting points for gas taps and other attachments (additional to the gas taps) to the rail by drilling through the double thickness of the flange, and these apertures in the flange may be sealed either by the step which provides the aperture, or with the use of sealing members located for example on either side when a screw or stud is passed through the aperture to fix components to the rail.

However, in an alternative form of the invention, the circular tube is formed :to a D shape without such flanges, and attachments are provided for fixing gas taps to the tube by drilling the tube wall of the flat face. It is preferred to use a spin-piercing or flowdrilling operation which causes the metal around the periphery of the aperture to be raised to form a thickened collar. This allows a larger number of screw-threads to be made in the collar than would be possible if the wall were merely pierced.

The ends of the rail may be flattened and folded to form gas-tight seals, and according to a feature of the invention the flattened portions are also bent to form integral brackets for mounting the rail in position. Alternatively end brackets may be brazed to the rail and also seal the ends.

As used herein, the term "tube" is to be understood to refer to a tubular article which is traded in commerce as a raw material in contrast with tubular fabrications which are generally produced during the production of a final commercial article.

Reference is now made to various embodiments of the invention illustrated in the accompanying drawings, wherein: Figures 1-3 show three profile rolled gas rails of different sections; and Figures 4 and 5 show alternative ways of closing off the ends of the gas rail.

Figures 1-3 each show a gas rail which has been formed, by means of a profile rolling or pressing operations from a length of light weight round-section steel tube.

In Figure 1, the tube is formed so that the resulting gas rail has a flat wall 10 on one side and a wall 12 of hat-shaped section on the other side, the width of the hat-shaped portion being less than that of the flat wall so as to form double-thickness flanges 14 on each side of the hat-shaped portion. These flanges are pierced as at 16 to enable gas taps to be secured to the flat face of the gas rail. In practice holes will also be formed in the wall 10 in registry with the interior of the passage 18 to afford communication between the gas taps and the passage 18.

Figure 2 shows a similar profile to that of Figure 1 except that the wall 12 has a D-shaped portion.

In Figure 3, the gas rail is formed to a D-shape without flanges. In this case, the flat wall 20 is formed with apertures 22 by means of the known flow drilling technique by means of which a collar of material 24 is produced so that the apertures 22 can be tapped for a greater length than would be possible if produced by piercing.

As shown in Figure 4, each end of the gas rail is flattened to form gas tight seals and is bent to form an integral mounting bracket 28. Figure 5 shows a modification in which the ends of the gas rail are sealed by plates 30 which are brazed as at 32 and act as mounting brackets.

WHAT WE CLAIM IS: 1. A gas rail made from a lightweight steel tube which has been formed from its initial shape to a cross-section provided with at least one flat face, said one flat face being formed with one or more holes in registry with the interior of the tube and having one or more control taps mounted thereon to control supply of gas from a respective hole.

2. A gas rail as claimed in Claim 1 in which said steel tube has a welded seam.

3. A gas rail as claimed in Claim 1 or 2 in which the tube has an internal passage extending centrally of said one flat face and is flanked on either side thereof by flanges, and in which the or each control tap is attached to said one flat face by means of fasteners engaging in holes in said flanges.

4. A gas rail as claimed in Claim 3 in which said passage is of generally rectangular or D-section.

5. A gas rail as claimed in Claims 1 or 2 in which said formed tube is of D-section and is unflanged.

6. A gas rail as claimed in any one of Claims 1-5 in which the tube is flattened at each end thereof to seal the ends and the flattened ends are bent to form mounting brackets.

7. A gas rail as claimed in any one of Claims 1-5 in which the tube is closed at each end thereof by a plate which also forms a mounting bracket.

8. A gas rail substantially as hereinbefore described with reference to, and as shown in, any one of Figures 1-5 of the accompanying drawings.

9. A method of making a gas rail wherein a length of lightweight steel tube is subjected to a forming operation to produce a tube cross-section provided with at least one flat face, asaid one flat face is formed with one or more holes in registry with the interior of the tube, and one or more gas taps are attached to said one flat face so as to control gas supply from a respective hole.

10. A method as claimed in Claim 9 in which said steel tube is of round-section prior to the forming operation.

11. A method as claimed in Claim 9 or 10 wherein said forming operation creates flanges which are co-planar with said one flat face and which project laterally from each side of that portion of the formed tube defining the internal passage of the gas rail, each flange comprising adjacent portions of the tube wall which have been brought into face-to-face contact by said forming operation.

12. A method as claimed in Claim 11 including attaching the or each control tap to said one flat face by means of fasteners engaging in holes in said flanges.

13. A method as claimed in any one of Claims 9-12 including flattening said tube at each end thereof to seal the ends and bending the flattened ends to form mounting brackets.

14. A method as claimed in any one of Claims 9-12 including attaching a plate to each end of the tube to seal the ends thereof and so that each plate projects laterally of the tube to form a mounting bracket.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. be made in the collar than would be possible if the wall were merely pierced. The ends of the rail may be flattened and folded to form gas-tight seals, and according to a feature of the invention the flattened portions are also bent to form integral brackets for mounting the rail in position. Alternatively end brackets may be brazed to the rail and also seal the ends. As used herein, the term "tube" is to be understood to refer to a tubular article which is traded in commerce as a raw material in contrast with tubular fabrications which are generally produced during the production of a final commercial article. Reference is now made to various embodiments of the invention illustrated in the accompanying drawings, wherein: Figures 1-3 show three profile rolled gas rails of different sections; and Figures 4 and 5 show alternative ways of closing off the ends of the gas rail. Figures 1-3 each show a gas rail which has been formed, by means of a profile rolling or pressing operations from a length of light weight round-section steel tube. In Figure 1, the tube is formed so that the resulting gas rail has a flat wall 10 on one side and a wall 12 of hat-shaped section on the other side, the width of the hat-shaped portion being less than that of the flat wall so as to form double-thickness flanges 14 on each side of the hat-shaped portion. These flanges are pierced as at 16 to enable gas taps to be secured to the flat face of the gas rail. In practice holes will also be formed in the wall 10 in registry with the interior of the passage 18 to afford communication between the gas taps and the passage 18. Figure 2 shows a similar profile to that of Figure 1 except that the wall 12 has a D-shaped portion. In Figure 3, the gas rail is formed to a D-shape without flanges. In this case, the flat wall 20 is formed with apertures 22 by means of the known flow drilling technique by means of which a collar of material 24 is produced so that the apertures 22 can be tapped for a greater length than would be possible if produced by piercing. As shown in Figure 4, each end of the gas rail is flattened to form gas tight seals and is bent to form an integral mounting bracket 28. Figure 5 shows a modification in which the ends of the gas rail are sealed by plates 30 which are brazed as at 32 and act as mounting brackets. WHAT WE CLAIM IS:

1. A gas rail made from a lightweight steel tube which has been formed from its initial shape to a cross-section provided with at least one flat face, said one flat face being formed with one or more holes in registry with the interior of the tube and having one or more control taps mounted thereon to control supply of gas from a respective hole.

2. A gas rail as claimed in Claim 1 in which said steel tube has a welded seam.

15. A method as claimed in any one of

Claims 9-14 in which said forming operation comprises a profile-rolling step.

1. A method as claimed in any one of Claims 9-14 in which said forming operation comprises a pressing operation.

17. A method substantially as hereinbefore described with reference to, and as shown in, any one of Figures 1-5 of the accompanying drawings.