GB1585273A

GB1585273A - Nozzles

Info

Publication number: GB1585273A
Application number: GB2124276A
Authority: GB
Original assignee: PEEL JONES COPPER PRODUCTS Ltd
Current assignee: PEEL JONES COPPER PRODUCTS Ltd
Priority date: 1977-05-19
Filing date: 1977-05-19
Publication date: 1981-02-25

Description

(54) IMPROVEMENTS IN OR RELATING TO NOZZLES (71) We, PEEL JONES COPPER PRODUCTS LIMITED, a British Company of 6 Gold Tops, Newport, Gwent NPT 4PG, Wales, Great Britain, 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 is concerned with tuyeres and like nozzles (all hereinafter referred to as tuyeres) for introducing air or other gases into furnaces or other high temperature enclosures.

It is an object of the invention to provide a tuyere which can be kept in operation for at least a limited length of time after failure of inter-nesting members, whereby on failure of one member the other(s) can be reused.

The invention accordingly provides a tuyere for furnaces and the like, comprising an inner member having a through bore (for the passage of air or other gases) and an internal coolant passage, and one or more outer members encircling the inner member along at least substantially the whole of the axial length thereof and covering the inner member around the exit of said bore, the or each outer member having an internal coolant passage, and a layer of refractory material being provided between the inner member and the encircling outer member.

A single outer member may be provided, having an inwardly directed flange or nose at one end thereof. Alternatively, there may be provided one outer member coextensive axially with the inner member, and another, annular, member covering the end faces of the inner and the first-mentioned outer members.

The coolant passages may be annular cavities, or may be provided by coiled tubing.

Embodiments of the invention will now be described, by way of example, referring to the accompanying drawings, in which: Fig. 1 is an end view of a tuyere embodying the invention, with cover plates removed; Fig. 2 is à cross-section on the lineA--A of Fig. 1; Fig. 3 is a cross-section on the line B-B of Fig. 1; Fig. 4 is a cross-section on the line C-C of Fig. 1; Figs. 5 and 6 are cross-sections of further embodiments; Fig. 7 is a partial cross-section of another embodiment; and Fig. 8 is a schematic perspective view of a tuyere according to the invention and associated coolant piping.

Referring to Figs. 1 to 4, the tuyere in accordance with the invention comprises a substantially cylindrical inner member 10, a generally cylindrical outer member 12, and a nose member 14. These three members contain coolant passages 16, 18, 20 respectively which in use provide a circulating flow of cooling water. The nose member 14 is provided with annular locating rings 22 co-operating with corresponding grooves on the outer end faces of the members 10 and 12, and is secured to these by means of clamping bolts such as the bolts 24 seen in Figure 3, which engage screw-threaded bores in the nose member 14 and at the other end of the assembly bear against an annular cover plate 26.

As also can be seen in Figure 3, a pipe 28 has one and screw-threaded into the nose member 14 where the pipe 28 communicates with the coolant passage 20. The other end of the pipe 28 is welded to the cover plate 26 and has welded thereto a screw-threaded socket connection 30. A similar pipe (not seen in the drawings) provides a coolant outlet for the nose member coolant passage 20.

Figure 4 illustrates the provision of coolant connections to the inner and outer members 10 and 12. The respective chamber 16, 18 is flared adjacent to the inner end wall of the assembly and is provided with a screwthreaded bore 32, 34 to receive a coolant connection.

The annular space between the inner member 10 and the outer member 12 is filled with a refractory material 36 which may for example be of graphite or silicon nitride.

Gaskets 38 and 40 are provided between the members in the axial direction.

The members 10, 12 and 14 are preferably of copper and may be cast using cores, or fabricated.

In normal operation, the tuyere of this embodiment would be connected to a water supply system as seen in Fig. 8 such that cooling water flows from an inlet 81 via a conduit 82 to and through the nose member 14, then to and through the outer member 12 and thence through an outlet 83 in series, the water flow through the inner member 10 being independent, by means of an inlet 84 and an outlet 85. On failure of the tuyere, which would normally occur in the nose area, the water supply may be changed by means of valves 86, 87 so that the inner and outer members continue to be cooled independently, the water supply to the nose member being cut off; in this mode of operation the tuyere continues to have approximately 95 per cent of its normal rate of heat extraction, and can be kept in use until it is convenient to replace the tuyere or until the outer member 12 also fails.The changeover may be made manually or automatically in response to operation of an alarm 88 which detects a difference between the inflow and outflow of coolant.

The inner member 10, and the outer member 12 where appropriate, may then be reused.

Figure 5 illustrates a further embodiment in which an outer coolant chamber 51 and nose coolant chamber 52 are formed in a single outer member 53. The inner member 54 is formed with an integral flange 55 to obviate the use of a separate cover plate at the inner end of the assembly.

In the embodiment of Figure 6, an inner member 60 having an end flange 61 and an outer member 62 are provided, there being only two coolant chambers 63 and 64. The outer member 62 has formed integrally therewith an outer end flange 65 which covers the outer end of the inner end 60.

Figure 7 shows an embodiment similar to that of Figure 6. In this embodiment however the coolant flow is conducted through coiled tubes. The inner member 71 contains a single coiled tube 72. The outer member 73 preferably contains a coiled tube 74 along most of its length and a nose end turn of tubing 75 forming a separate nose cooling system. Alternatively the coil in the outer member may be a single coil to give a double cooling system for the assembly rather than a triple cooling system.

The tuyeres of Figures 5, 6 and 7 are also preferably connected in use in the circuit shown in Figure 8.

The coolant circuits in the embodiments of Figs. 1 to 4, 5 and 6 described above may also be formed by coiled tubing cast or otherwise incorporated in the various members of the tuyere assembly.

WHAT WE CLAIM IS: 1. A tuyere for furnaces and the like, comprising an inner member having a through bore for the passage of air or other gases and an internal coolant passage, and one or more outer members encircling the inner member along at least substantially the whole of the axial length thereof and covering the inner member around the exit of said bore, the or each outer member having an internal coolant passage, and a layer of refractory material being provided between the inner member and the encircling outer member.

2. A tuyere according to claim 1, in which there is provided a single outer member having an inwardly directed nose at one end thereof covering the exit end of the inner member.

3. A tuyere according to claim 1, in which a first outer member is coextensive axially with the inner member, and a second, annular outer member covers the end faces of the inner member and the first outer member.

4. A tuyere according to any preceding claim, in which the coolant passage in each member is provided by an annular cavity therein.

5. A tuyere according to any of claims 1 to 3, in which the coolant passage in each member is formed by coiled tubing embedded therein.

6. A tuyere according to any preceding claim, in which the refractory material is graphite or silicon nitride.

7. A tuyere substantially as hereinbefore described with reference to and as shown in Figures 1 to 4 or any of Figures 5 to 7 of the accompanying drawings.

8. A tuyere according to any preceding claim in combination with a first coolant circuit for supplying coolant to the inner member and a second coolant circuit for supplying coolant to the or one of the outer members, the second coolant circuit including a valve actuable to prevent coolant flow to the respective outer member.

9. The combination of claim 8, including a sensor arranged to actuate said valve in response to loss of coolant from the outer member.

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. The members 10, 12 and 14 are preferably of copper and may be cast using cores, or fabricated. In normal operation, the tuyere of this embodiment would be connected to a water supply system as seen in Fig. 8 such that cooling water flows from an inlet 81 via a conduit 82 to and through the nose member 14, then to and through the outer member 12 and thence through an outlet 83 in series, the water flow through the inner member 10 being independent, by means of an inlet 84 and an outlet 85. On failure of the tuyere, which would normally occur in the nose area, the water supply may be changed by means of valves 86, 87 so that the inner and outer members continue to be cooled independently, the water supply to the nose member being cut off; in this mode of operation the tuyere continues to have approximately 95 per cent of its normal rate of heat extraction, and can be kept in use until it is convenient to replace the tuyere or until the outer member 12 also fails.The changeover may be made manually or automatically in response to operation of an alarm 88 which detects a difference between the inflow and outflow of coolant. The inner member 10, and the outer member 12 where appropriate, may then be reused. Figure 5 illustrates a further embodiment in which an outer coolant chamber 51 and nose coolant chamber 52 are formed in a single outer member 53. The inner member 54 is formed with an integral flange 55 to obviate the use of a separate cover plate at the inner end of the assembly. In the embodiment of Figure 6, an inner member 60 having an end flange 61 and an outer member 62 are provided, there being only two coolant chambers 63 and 64. The outer member 62 has formed integrally therewith an outer end flange 65 which covers the outer end of the inner end 60. Figure 7 shows an embodiment similar to that of Figure 6. In this embodiment however the coolant flow is conducted through coiled tubes. The inner member 71 contains a single coiled tube 72. The outer member 73 preferably contains a coiled tube 74 along most of its length and a nose end turn of tubing 75 forming a separate nose cooling system. Alternatively the coil in the outer member may be a single coil to give a double cooling system for the assembly rather than a triple cooling system. The tuyeres of Figures 5, 6 and 7 are also preferably connected in use in the circuit shown in Figure 8. The coolant circuits in the embodiments of Figs. 1 to 4, 5 and 6 described above may also be formed by coiled tubing cast or otherwise incorporated in the various members of the tuyere assembly. WHAT WE CLAIM IS:

1. A tuyere for furnaces and the like, comprising an inner member having a through bore for the passage of air or other gases and an internal coolant passage, and one or more outer members encircling the inner member along at least substantially the whole of the axial length thereof and covering the inner member around the exit of said bore, the or each outer member having an internal coolant passage, and a layer of refractory material being provided between the inner member and the encircling outer member.