Patent ID: 8123591

Claim:
An abrasive supply system, comprising: an abrasive tank configured to hold abrasive particles; a substantially atmospheric pressure abrasive hopper configured to selectively deliver abrasive particles to the abrasive tank; an abrasive delivery tube operatively coupled to the abrasive tank and configured to convey gas-entrained abrasive particles; and a substantially constant flow rate gas source configured to pressurize the abrasive tank and propel abrasive particles through the abrasive delivery tube; wherein the abrasive supply system is configured for cooperation between the substantially constant flow rate gas source, the abrasive tank, and the abrasive delivery tube to automatically detect a reduced amount of abrasive in the abrasive tank, responsively depressurize the abrasive tank, and refill the abrasive tank with abrasive particles from the abrasive hopper.