The Flail Mower / Mulcher is one of the hardest hydraulically driven attachments to get to work correctly on an excavator. To run correctly it needs a constant flow and pressure and to use the attachment all the machine functions need to be operated. Running the flail from the hammer circuit auxiliary spool is not usually an option as when the other machine services are used, they will be given priority causing the attachment speed to slow down or stop. For this reason a double priority flow control valve is used. This valve is fitted into the two main pump lines between the pump and main valve block. When the valve is switched off the machine functions as normal, when the valve is electrically switched on usually with a latching switch circuit, the valve then takes an equal amount of flow and pressure from each pump to feed direct to the attachment, the remaining flow not required by the attachment is sent to the machine main control valve to allow the other functions to be used at a reduced speed.
