Feeder assembly for particle blast system

A particle blast system comprising:

• a) a source of blast media;
• b) a discharge nozzle for expelling blast media from said system;
• and
• c) a feeder configured to transport blast media from said source into a flow of transport gas, said feeder assembly comprising:
• i) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• ii) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a first position and a second position when said rotor is rotated about said axis;
• iii) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas;
• iv) a seal having a first surface contacting at least a portion of said peripheral surface, said first surface having at least one first opening and at least one second opening spaced apart from each other, said at least one first opening being in fluid communication with said inlet, said at least one second opening being in fluid communication with said outlet;
• and
• v) said transport gas being able to flow from said at least one first opening to said at least one second opening through those of said plurality of pockets disposed between said first and second positions.

A feeder configured to transport blast media from a source into a transport gas flow, said feeder assembly comprising:

• a) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• b) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a first position and a second position when said rotor is rotated about said axis;
• and
• c) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas, said inlet being in fluid communication with said outlet through those of said plurality of pockets disposed between said first and second positions.

A method of delivering blast media to a discharge nozzle, comprising the steps of:

• a) providing a rotor configured to introduce said blast media into a flow of pressurized transport gas, said rotor having a first rotor surface;
• b) providing a seal, said seal having a first seal surface disposed adjacent said first rotor surface;
• c) starting rotation of said rotor prior to exerting any substantial force by said first seal surface on said first rotor surface;
• d) after rotation of said rotor has started, exerting force by said first seal surface on said first rotor surface, forming a seal therebetween sufficient to prevent any substantial leakage of said pressurized transport gas across said formed seal.

A seal configured for use in feeder of a particle blast system, said feeder having a rotor, said rotor having a peripheral surface and at least one pocket formed in said peripheral surface, said rotor being rotatable about an axis of rotation, said at least one pocket being cyclically disposed adjacent a first position when said rotor is rotated, said at least one pocket being configured to discharge blast media therefrom at said first position, said seal comprising:

• a) said first surface configured to contact at least a portion of said peripheral surface, said first surface defining one surface of at least one wall, said wall including at least one second surface spaced apart from said first surface;
• b) at least one passageway configured for said blast media to flow therethrough;
• c) at least one opening in said first surface, said at least one passageway in fluid communication with said at least one opening;
• and
• d) said wall being sufficient flexible to transmit a substantial portion of fluid pressure exerted against said at least one second surface to said peripheral surface.

A feeder configured to transport blast media from a source into a flow of transport gas, said feeder assembly comprising:

• a) a first opening and a second opening, said first and second opening being spaced apart from each other, each opening having a respective inner diameter;
• b) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• c) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed at a first location at which blast media is delivered thereinto, and a second location at which at least a portion of said blast media is discharged therefrom;
• and
• d) said rotor having a first portion of said peripheral surface, said first portion having a diameter configured to be received and supported by said inner diameter of said first opening, said rotor having a second portion of said peripheral surface, said second portion having a diameter configured to be received and support by said inner diameter of said second opening, said diameter of said first portion being no larger than said inner diameter of said second opening, said peripheral surface having a maximum diameter between said first portion and said second portion no greater than the inner diameter of said second opening of said second portion
• whereby said rotor may be installed in said feeder by inserting said first portion first through said second opening to a position at which said first portion is received and supported by said first opening, said second portion being received and supported by said second opening at said position.

A feeder configured to transport blast media from a source into a flow of transport gas, said feeder comprising:

• a) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• b) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a first position and a second position when said rotor is rotated about said axis;
• c) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas;
• d) a seal having a first surface contacting at least a portion of said peripheral surface, said first surface having at least one first opening disposed adjacent said peripheral surface, said seal defining a first passageway which is in fluid communication with said at least one first opening and with said inlet, said seal defining a second passageway which is in fluid communication with said at least one first opening and said outlet, said first passageway being in fluid communication with said second passageway at said at least one first opening.

A feeder configured to transport blast media from a source into a flow of transport gas, said feeder comprising:

• a) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• b) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a charge position at which blast media is introduced into said pockets and a discharge position at which blast media is discharged from said pockets;
• c) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas, a portion of said transport gas flowpath being disposed adjacent said discharge position such that blast media discharged from said pockets is carried therefrom by the transport gas;
• d) a seal having a first surface contacting at least a portion of said peripheral surface at said discharge position, said seal configured to seal against a pressure of the transport gas of at least approximately 30 PSIG;
• and
• e) said rotor having a diameter no greater than approximately four inches.

A feeder configured to transport blast media from a source into a flow of transport gas, said feeder comprising:

• a) a rotor having a peripheral surface, said rotor having a sealed width and a diameter, said rotor being rotatable about an axis of rotation;
• b) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a charge position at which blast media is introduced into said pockets and a discharge position at which blast media is discharged from said pockets;
• c) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas, a portion of said transport gas flowpath being disposed adjacent said discharge position such that blast media discharged from said pockets is carried therefrom by the transport gas;
• d) a seal having a first surface contacting at least a portion of said peripheral surface across said sealed width at said discharge position,;
• and
• e) said rotor having a ratio of said diameter to said sealed width approximately no greater than 1:2.

A feeder configured to transport blast media from a source into a flow of transport gas, said feeder comprising:

• a) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• b) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a charge position at which blast media is introduced into said pockets and a discharge position at which blast media is discharged from said pockets;
• c) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas, a portion of said transport gas flowpath being disposed adjacent said discharge position such that blast media discharged from said pockets is carried therefrom by the transport gas;
• d) a seal having a first surface contacting at least a portion of said peripheral surface at said discharge;
• and
• e) said rotor having no substantial axial force being exerted thereon.

A feeder configured to transport cryogenic blast media from a source into a flow of transport gas, said feeder comprising:

• a) a rotor having a peripheral surface, said rotor being rotatable about an axis of rotation;
• b) a support structure, said rotor being rotatably supported by said support structure;
• c) a plurality of pockets disposed in said peripheral surface, each of said plurality of pockets being cyclically disposed between a charge position at which blast media is introduced into said pockets and a discharge at which blast media is discharged from said pockets;
• d) a transport gas flowpath, said transport gas flowpath having an inlet and an outlet, said inlet being configured to be connected to a source of transport gas, a portion of said transport gas flowpath being disposed adjacent said discharge position such that blast media discharged from said pockets is carried therefrom by the transport gas;
• e) a seal having a first surface contacting at least a portion of said peripheral surface at said discharge position;
• and
• f) substantially all heat gain to or heat loss from said rotor is from contact between the blast media and said rotor and from said transport gas flowing through said pockets.

A method of delivering blast media to a discharge nozzle, comprising the steps of:

• a) providing a rotor configured to introduce said blast media into a flow of pressurized transport gas at a discharge station, said rotor having a first rotor surface, said rotor having a diameter no greater than approximately four inches;
• b) providing a flow of transport gas having a pressure of at least approximately 30 PSIG;
• and
• c) sealing between said first rotor surface and said discharge station sufficient to prevent any substantial leakage of said pressurized transport gas.