US Patent 7850824 Apparatus for cleaning paper machine press fabrics on-the-run

An apparatus is described for cleaning papermaking felt by applying a low concentration of a cleaning solution through the oscillating needle nozzles. The detergent is applied intermittently while paper is being manufactured. Each cleaning period lasts for at least the length of time required for the nozzles to cover the entire surface of the felt, and preferably twice that period of time. The application of cleaning solution is then discontinued for a period of time. This cycle is repeated continuously as the paper is being manufactured. The apparatus includes a first cleaning chemical reservoir, a second cleaning chemical reservoir, a high pressure pump coupled to the first and second reservoirs, and a control unit having programming for selectively injecting the chemicals.