Paper making machine head-box - has suspension feed channel and throat provided with vertical draw off and return flow ducts terminating in venting chamber

摘要

Paper web making machine has head box forming with the wire mesh screen a suspension feed duct terminating in a throat between which is provided an upwardly extending draw off duct. Parallel to the duct is arranged a return flow duct. This extends over the whole width of the formed web and serves for returning the suspension drawn off by duct which is separated from the duct by a vertically displaceable partition member extending into a venting chamber. Uniformly deposited suspension layer is achieved.