A METHOD FOR OPERATION TO EXCAVATE UNDERDRAIN IN THE FIELD GROUND AND A DEVICE FOR OPERATION TO EXCAVATE UNDERDRAIN

摘要

A method of operation to effectively excavate anunderdrain in the field ground having a long service life andensuring that the underdrain will not be closed after a longperiod of time and a device for such operation. The methodcomprises attaching a plurality of buckets to an endless chain,driving said endless chain to excavate a slit in the field ground,reforming inner side walls of the slit by a reformer, pressingearth from both sides of the slit laterally inwardly by a pressingmember attached to the reformer to form a block to separatesaid slit into an upper space and a lower space, and chargingthe upper space with discarded dirt.