Abstract: Methods of controlling a downhole tool in a well are disclosed wherein pressure change signals are introduced into a column of fluid standing in the well. The command signal includes at least one high level pressure change applied to the column of fluid. The high level pressure change includes a change from a first value to a second value, with the second value being at least about 1,000 psi above hydrostatic pressure of the column of fluid in the well, and with pressure being maintained at the second value for an interval of time corresponding to information stored in a control system of the downhole valve. A number of suitable command signal formats are disclosed, particularly including pressure drop signals.

Abstract: An apparatus for processing soil in a subterranean earth situs. The apparatus includes a parallelogram spotter or positioning portion with a drilling table support portion connected thereto. A rotary drilling table is mounted on the drilling table support portion. Relative movement is provided between the support portion and the positioning portion in a plurality of planes. A pivotation portion is disposed between the support portion and the positioning portion and pivotally connected thereto. Hydraulic cylinders are provided to shift the apparatus about a vertical axis, to move the drilling table support portion in a longitudinal direction, to tilt the pivotation portion and support portion about a horizontal axis and to tip the support portion with respect to the pivotation portion about a longitudinal axis. A table elevation winch is mounted on the support portion and has a table elevation cable extending therefrom which is engaged with a pulley connected to the support portion.