Apparatus for receiving downhole acoustic signals
The invention relates to an apparatus for receiving downhole acoustic signals, processing the signals into electric signals, then transmitting the signals wirelessly to a remote above-surface monitoring station. The apparatus is mountable to an above-surface rotatable component used in borehole application. The apparatus includes an instrument housing, and a clamping assembly attached to the housing and having sufficient length and flexibility to enable the apparatus to surround the perimeter of the rotatable component.
1. An apparatus for receiving downhole acoustic signals, comprising:
(a) at least one instrument housing made of an acoustically conductive material, and comprising a contacting portion contactable with a rotatable above-surface component used in borehole applications, in such a manner that acoustic signals from the rotatable above-surface component is conducted through the housing;
(b) instruments inside the housing comprising a transducer for converting acoustic signals conducted through the housing into electric signals, a data acquisition circuit communicative with the transducer, and a wireless transmitter communicative with the data acquisition circuit and for wirelessly transmitting the electric signals to a remote destination; and
(c) a clamping assembly attached to the instrument housing and having sufficient length and flexibility to enable the apparatus to surround the perimeter of the rotatable above-surface component, and comprising a fastener configured to removably fasten the apparatus to the rotatable above-surface component, thereby enabling the apparatus to operate while the rotatable above-surface component is rotating.
2. The apparatus of claim 1 wherein the clamping assembly further comprises a plurality of members each pivotably connected to one or more of another member, the housing, and the fastener.
3. The apparatus of claim 2 wherein at least some of the members are removable, thereby enabling the clamping assembly length to conform to the perimeter of the rotatable above-surface component.
4. The apparatus of claim 2 wherein the housing contacting surface further comprises at least one contact tooth.
5. The apparatus of claim 1 wherein the rotatable above-surface component is selected from the group of a kelly and a saver sub of a drilling rig.
6. The apparatus of claim 2 comprising a plurality of housings pivotably connected to one or more of another housing, the clamping assembly member, and the fastener.
7. The apparatus of claim 6 wherein a pair of housings are adjacent to each other and each have a conduit opening, and the acoustic signal receiver further comprises a flexible conduit connected at each end to a conduit opening, and an electrical connector passing through the conduit and electrically connecting the instruments in one housing to the instruments in the adjacent housing.
8. The apparatus of claim 1 wherein the housing further comprises an RF transparent portion, and an RF antenna mounted inside the housing such that the antenna can receive and transmit RF energy through the RF transparent portion.