Method and device for mounting and withdrawing a plasma torch relative to an apparatus operating under pressure and temperature conditions precluding a direct intervention
AssigneeAerospatiale Societe Nationale Industrielle
InventorsJean Feuillerat, Yves H. G. Valy
Life of this patent
Estimating the term…
Abstract
A method and device for forming a modifiable closed volume (16) by means of an extensible and retractable tubular element (16) fixed around the orifice of a sleeve (3) closed by a valve (5) on the upstream side of the valve, and detachably fixed around the nose (12) of the torch (4), and balancing the pressure in the volume (16) on the upstream side of the valve with the pressure prevailing on the downstream side of the valve by a device (20, S), opening the valve and reducing the volume (16) by advancing to the mounted position the nose (12) of the torch and locking the torch (4) on a sealing element (7) of the sleeve.
Claims9
Method for mounting a plasma torch having a nose and a non-transferred arc on an end of a sleeve which comprises a valve and communicates with a blast pipe of an apparatus operating under high temperature and high pressure conditions, and for withrawing the torch, said method comprising, for mounting the torch:
- (a) forming a modifiable closed volume on a upstream side of the valve between the valve and an end of the torch,
- (b) balancing pressure in said volume with a pressure prevailing on a downstream side of the valve,
- (c) opening the valve,
- (d) reducing said volume by advancing the nose of the torch to a mounted position of the torch through said valve, and, for withdrawing the torch:
- (e) increasing said volume by rearwardly shifting the nose of the torch,
- (f) closing the valve,
- (g) bringing said volume to atmospheric pressure which is lower than the pressure prevailing on the downstream side of the valve,
- (h) opening said volume.
A device adapted for mounting a plasma torch having a non-transferred arc and a nose portion on an end of a sleeve which communicates with a blast pipe of an apparatus operating under high temperature and high pressure conditions, and adapted for withdrawing the plasma torch from the apparatus, said device comprising:
- a sleeve adapted for receiving a plasma torch nose portion and containing a shut-off valve;
- an extensible and retractable tubular element provided upstream of the shut-off valve and sealably fixed at one end around an end of said sleeve and adapted to receive a nose end of the torch, said tubular element being attachable at its opposite end around said torch nose;
- and
- means for balancing pressure inside said tubular element with a pressure prevailing downstream of the shut-off valve.
A device adapted for mounting a plasma torch having a non-transferred arc and a nose portion on an end of a sleeve which communicates with a blast pipe of an apparatus operating under high temperature and high pressure conditions, and adapted for withdrawing the plasma torch from the apparatus, said device comprising:
- a sleeve adapted for receiving a plasma torch nose portion and containing a shut-off valve;
- an extensible and retractable tubular element provided upstream of the shut-off valve, said tubular element being sealably fixed at one end around an end of said sleeve and adapted to receive a nose end of the plasma torch, said tubular element being telescopic metal members attachable at its opposite end around said torch nose;
- means for locking said tubular element onto the torch;
- and means for balancing pressure inside said tubular element with a pressure prevailing downstream of the shut-off valve.
Dependencies are inferred from the claim text.