GB2098688A

GB2098688A - A double connector union for a gas meter

Info

Publication number: GB2098688A
Application number: GB8114882A
Authority: GB
Original assignee: G Kromschroeder AG
Current assignee: Elster Kromschroeder GmbH
Priority date: 1981-05-15
Filing date: 1981-05-15
Publication date: 1982-11-24
Also published as: ATA211081A; NL192137C; BE888839A; AT387852B; CH651389A5; NL192137B; NL8102302A; GB2098688B

Abstract

To ensure a fireproof connection between a double connector union 12 and the casing 10 of a gas meter, the union is provided with an outer tubular member 40 made of a material with a relatively high melting point, such as steel, the coaxial tubes 38 and 44 and connecting webs 34 of the union being formed as a casting made of a material which can be easily cast, such as brass, which has a relatively low melting point. The tubular member 40 is provided with a collar 52 in which is fitted an opening in the meter casing. A steel ring 56 may be provided on the inside of the casing 10 around the collar 52, the inner edge of the opening being flanged between the collar 52 and the ring 56 so that the collar is a force-fit in the opening. <IMAGE>

Description

SPECIFICATION A double connector for a gas meter and a gas meter provided therewith This invention relates to a double connector union for a gas meter, comprising two coaxial tubes connected together by radial webs.

The invention also extends to a gas meter provided with such a union.

Such unions and gas meters are disclosed, for example, in German AS 1 113 616, German specification 1 loo 997 and United States specification 2 807 959.

Usually, the double connector union is produced as a one-part casting comprising the inner tube, the webs and the outertube. For this purpose, a material has been used in practice which facilitates this production as a casting, for example brass. However, it is desired to make a gas meter as fireproof as possible. In a fire, the gas meter must remain sealed for a long period of time and the escape of gas must be prevented. This fireproofing is not achieved with a double connector union made solely of brass since when using brass the flanged edge, by means of which the double connector union is fixed to the meterhousing, softens at high temperatures and becomes unsealed.

The invention is based on the problem of producing a double connector union for a gas meter with little The invention is based on the problem of so constructing the double connecting union in a gas meter of the type defined above with little expenditure that a fireproof fixing to the gas meter housing is possible.

This problem is solved in accordance with the invention in that the double connecting union has a tubular outer portion made of steel into which is forced a casting of an easily castable material forming the inner tube, the webs and an inner tubular jacket surrounding the tube coaxially.

Moreover, the tubular outer portion can be produced as a turned part made of steel and be connected in a fireproof manner to the gas meter hous ing.The innertubetogetherwiththewebs is produced as a casting together with an inner jacket.

Moreover, a material such as brass can be used which may be easily cast. This casting is forced into the outer portion. It would be very difficult to produce the entire, relatively complicated, double connecting union as a steel part can be connected to the gas meter housing by flanging or the like.

Developments of the invention are the subject matter of the sub-ciaims.

An embodiment of the invention is described in detail in the following with reference to the accompanying drawings, by way of example: Figure 1 is a side view of a gas meter with a single connector, partially in section, in association with a pipe connecting portion likewise provided with a single connector; Figure 2 shows a section along the line Il-Il in Figure 1.

A double connector union 12 which forms an annular outer inlet dubt 14 and an inner outlet dubt 16 coaxial thereto is mounted on a gas meter housing 10 produced from sheet metal. The outlet duct 16 is in communication with the measuring mechanism union 18 of the gas meter. The gas meter can be incorporated in a gas line (not shown) by means of a pipe connecting piece 20 shown in feint lines. The pipe connecting piece is made for example as a malleable casting. It includes two aligned simple connecting unions 22 and 24 and a double connecting union 26 the cross section of which corresponds to that of the double connection union 12. The double connection 26 comprises an annular outer duct 28 and an inner duct 30 arranged coaxiallythereto. The outer duct 28 is in communication with the connector union 22 and the inner duct is in communication with the connector union 24.The double connector union 12 of the gas meter is connected to the double connector union 26 of the pipe connector piece 20 by means of a cup nut 32 with the interposition of a sealing ring 35. The gas path extends from the connector union 22 through the duct 28 and the duct 14 to the gas meter and from the measuring mechanism union 18 through the duct 16 and the duct 30 to the connector union 24.

The double connector union 12 consists of two tubes 36 and 38 connected to one another by radial webs 34 and arranged coaxiallyto one another.

Moreover, the double connector union 12 comprises a tubular outer portion 40 made of steel which can be turned from a tubular material and a casting 42.

The casting 42 forms the inner tube 38, the webs 34 and a tubular inner jacket44 coaxially surrounding the tube 38. This casting 42 is produced from a material such as brass which can be easily cast in a relatively complicated shape. The casting 42 is forced into the outer portion 40. Then, the outer portion 40 and the inner jacket 44 together from the outer tube 36 of the double connector union 12.

At its end remote from the gas meter housing, the tubular outer portion 40 has a bore 46 of larger diameter and at its end facing the gas meter housing has a bore 48 of smaller diameter. Between these bores 46 and 48 the outer portion 40 forms an inner annular shoulder 50. The casting 42 is forced into the bore 46 of larger diameter by means of its inner jacket 44. The inner diameter of the inner jacket 44 is equal to the diameter of the bore 48 so that a smooth walled passage is formed. The length of the inner jacket 44 is equal to the length of the bore 46. Thus, in the forced in condition, the inner jacket 44 rests on the annular shoulder 50 and seals intimately with the end surface of the outer portion 40.

At its end projecting into the gas meter housing 10 the outer portion 40 has a collar 52 with a reduced outer diameter, preferably knurled on the outside.

On the housing side of the inner annular shoulder 50, it forms an outer annular shoulder 54. On its outside, the collar 52 has a flange. The gas meter housing 10 consisting of a sheet metal has an opening at its top the diameter of which is substantially smaller than the outer diameter of the collar 52. On the inside of the gas meter housing 10, a steel ring 56 is arranged around the opening the inner diameter of which is substantially greater than the outer diame ter of the coller 52 by the thickness of the sheet metal but is smaller than the outer diameter of the outer portion 40. The outer portion 40 is forced into the opening together with the collar 52. Moreover, the inner edge 58 of the opening is bent inwards. The outer annular shoulder 54 of the outer portion 40 engages the outer surface of the gas meter housing 10.The collar 52 is flanged around the steel ring 56 with the bent inner edge 58 of the opening. In that way, a gas-tight fixing of the double connector union 12 to the gas meter housing is achieved which is fireproof to a considerable extent. Moreover, the flanging of the collar 52 is forced into the sheet metal of the edge 58 which improves the sealing and mounting. In addition, an adhesive can be applied to the outside of the collar 52 which particularly improves security against rotation.

The temperature resistant sealing ring 35 which preferably consists of asbestos, is mounted on the double connector union 12. The sealing ring 35 consists of two annular concentric members which are connected to one another by radial webs 60. The sealing ring 35 is centred in the end surface of the inner tube 38 by an edge 62. Moreover, it has a sheet metal edge of reversed L-shape in cross section (not shown) which is forced onto the outer portion 40 and secures the sealing ring 35 on the double connector union 12.

It will be appreciated that, since it is preferably made of steel, the tubular portion 40 consists of a material having a higher melting point than that of the casting 42, which is preferably made of brass.

Thus, since the tubular member 40 forms the flange connection with the meter housing, that connection is substantially more resistant to the effects of fire than it would be if the connection were made between the housing and a casting of brass or any other material of relatively low melting point.

Claims

CLAIMS 1. A double connector union for a gas meter, comprising a casting in the form of two coaxial tubes connected together by radial webs, the casting being fitted into a tubular member consisting of a material having a melting point higher than that of the casting material. 2. A union according to claim 1, in which the material of higher melting point is steel. 3. A union according to claim 1 or claim 2, in which the casting material is brass. 4. A union according to any one of claims 1 to 3 in which the casting is a force-fit in the tubular member. 5. A union according to claim 4, in which the tubular member has an inner stepped bore comprising a portion of larger diameter and a portion of smaller diameter, the casting being a force-fit in the portion of largerdiameter. 6. A union according to any preceding claim, in which one end ofthe tubular member is formed as a collar comprising a portion of reduced outer diameter forming a shoulder at a distance from the said one end of the tubular member. 7. A union according to claim 6, in which the outside of the collar is knurled. 8. A gas meter provided with a union according to claim 6 or claim 7, in which the gas meter has an opening in its housing, which is of smaller diameter than the outer diameter of the collar and is located in the portion of reduced outer diameter. 9. A gas meter according to claim 8, in which the meter housing consists of sheet metal and a steel ring is arranged on the inside of the meter housing around the opening in the housing, the inner diameter of the steel ring being larger than the outer diameter of the collar by the thickness of the sheet metal but smaller than the outer diameter of the tubular member. 10. A gas meter according to claim 9, in which the collar is a force-fit in the opening in the housing, the inner edge of the opening being bent inwards around the inside of the steel ring. 11. A gas meter according to claim 10, in which the collar end of the tubular member is flared outwardly so as to flange the sheet metal atthe housing opening against the steel ring. 12. A gas meter according to any one of claims 8 to 11, in which an adhesive is applied to the outside of the collar. 13. A gas meter according to any one of claims 8 to 12, provided with a double gas line connection attached to the end of the double connector union remote from the opening in the meter housing. 14. A gas meter according to claim 13, in which a temperature resistant sealing ring is arranged between the double gas line connection and the union. 15. A gas meter according to claim 14, in which the sealing ring consists of asbestos. 16. A double connector union for a gas meter, substantially as herein described with reference to the accompanying drawings. 17. A gas meter provided with a double connector union according to claim 1, substantially as herein described with reference to the accompanying drawings. Superseded claims 1 to 17

1. A double connector union for a gas meter, comprising a casting in the form of an inner tube provided with radial webs, the casting being fitted within a tubular member to provide coaxial inlet and outlet ducts for the passage of gas to and from the meter and the tubular member consisting of a material having a melting point higher than that of the material from which the inner tube is cast.

2. A double connector union according to claim 1, in which the casting also comprises an outer tube connected to the inner tube by the radial webs.

3. A union according to claim 1 or claim 2, in which the material of higher melting point is steel.

4. A union according to any one of claims 1 to 3, in which the casting material is brass.

5. A union according to any preceding claim, in which the casting is a force-fit in the tubular member.

6. A union according to claim 5, in which the tubular member has an inner stepped bore comprising a portion of larger diameter and a portion of smaller diameter, the casting being a force-fit in the portion of larger diameter.

7. A union according to any preceding claim, in which one end of the tubular member is formed as a collar comprising a portion of reduced outer diameterforming a shoulder at a distance from the said one end of the tubular member.

8. A union according to claim 7, in which the outside of the collar is knurled.

9. A gas meter provided with a union according to claim 7 or claim 8, in which the gas meter has an opening in its housing, which is of smaller diameter than the outer diameter of the collar and is located in the portion of reduced outer diameter.

10. A gas meter according to claim 9, in which the meter housing consists of sheet metal and a steel ring is arranged on the inside of the meter housing around the opening in the housing, the inner diameter of the steel ring being larger than the outer diameter of the collar by the thickness of the sheet metal but smaller than the outer diameter of the tubular member.

11. A gas meter according to claim 10, in which the collar is a force-fit in the opening in the housing, the inner edge of the opening being bent inwards around the inside of the steel ring.

12. A gas meter according to claim 11, in which the collar end of the tubular member is flared outwardly so as to flange the sheet metal at the housing opening against the steel ring.

13. A gas meter according to any one of claims 9 to 12, in which an adhesive is applied to the outside of the collar.

14. A gas meter according to any one of claims 9 to 13, provided with a double gas line pipe connecting piece attached to the end of the double connector union remote from the opening in the meter housing.

15. A gas meter according to claim 14, in which a temperature resistant sealing ring is arranged between the pipe connecting piece and the union.

16. A gas meter according to claim 15, in which the sealing ring consists of asbestos.

17. A gas meter according to any one of claims 14 to 16, in which the double connector union connected to the meter housing is connected to the pipe connecting piece through another double connector union as claimed in any one of claims 1 to 8.

18. A double connector union for a gas meter, substantially as herein described with reference to the accompanying drawings.

19. A gas meter provided with a double connector union according to claim 1, substantially as herein described with reference to the accompanying drawings.